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Shaw K, O'Rourke P, Del Mar C, Kenardy J. Psychological interventions for overweight or obesity. CochraneDatabase Syst Rev. 2005 Apr 18;(2):CD003818.

BOUTS TRADUIRE DONT 2 GROS

Public and Environmental Health Unit, Department of Health and Human Services, Public Health Unit, 3 / 90Davey Street, Hobart, Tasmania, Australia, 7000. [email protected]

BACKGROUND: Overweight and obesity are global health problems which are increasing throughout theindustrialised world. If left unchecked, they will continue to contribute to the ever increasing noncommunicabledisease burden.

FOND : Le poids en excs et la corpulence sont des problmes de sant globauxqui augmentent partout dans le monde industrialis. Si quitt de manireincontrle, ils continueront contribuer au fardeau de maladienoncommunicable jamais augmentant.

OBJECTIVES: To assess the effects of psychological interventions for overweight or obesity as a means ofachieving sustained weight loss.

OBJECTIFS : valuer les effets d'interventions psychologiques pour le poids enexcs ou la corpulence comme un moyen d'accomplir la perte de poids soutenue.

SEARCH STRATEGY: Studies were obtained from searches of multiple electronic bibliographic databases. Thedate of the latest search was June 2003.

FOUILLEZ LA STRATGIE : les tudes ont t obtenues des recherches de basesde donnes bibliographiques lectroniques multiples. La date de la dernirerecherche tait le juin de 2003.

SELECTION CRITERIA: Trials were included if the fulfilled the following criteria: 1) they were randomisedcontrolled clinical trials of a psychological intervention versus a comparison intervention, 2) one of the outcomemeasures of the study was weight change measured by any method, 3) participants were followed for at least

three months, 4) the study participants were adults (18 years or older) who were overweight or obese (BMI > 25kg/m(2)) at baseline.

CRITRES DE SLECTION : les Essais ont t inclus si le ralis les critressuivants : 1) ils taient des essais cliniques contrls de randomised d'uneintervention psychologique contre une intervention de comparaison, 2) une desmesures de rsultat de l'tude tait le changement de poids mesur parn'importe quelle mthode, 3) les participants ont t suivis depuis au moins troismois, 4) les participants d'tude taient des adultes (18 ans ou plus gs) quitaient obses ou obses (BMI> 25 kg/m (2)) la ligne des bases.

DATA COLLECTION AND ANALYSIS: Two people independently applied the inclusion criteria to the studies

identified and assessed study quality. Disagreement was resolved by discussion or by intervention of a thirdparty. Meta-analyses were performed using a fixed effect model.

COLLECTE DE DONNES ET ANALYSE : Deux personnes ont de faonindpendante appliqu les critres d'inclusion aux tudes la qualit d'tudeidentifie et value. Le dsaccord a t rsolu par la discussion ou parl'intervention d'une tierce personne. Les Meta-analyses ont t excutes enutilisant un modle d'effet fix.

MAIN RESULTS: A total of 36 studies met the inclusion criteria and were included in the review. Overall, 3495participants were evaluated. The majority of studies assessed behavioural and cognitive-behavioural weightreduction strategies. Cognitive therapy, psychotherapy, relaxation therapy and hypnotherapy were assessed ina small number of studies. Behaviour therapy was found to result in significantly greater weight reductions than

placebo when assessed as a stand-alone weight loss strategy (WMD -2.5 kg; 95% CI -1.7 to -3.3). Whenbehaviour therapy was combined with a diet / exercise approach and compared with diet / exercise alone, thecombined intervention resulted in a greater weight reduction. Studies were heterogeneous however the majority


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of studies favoured combining behaviour therapy with dietary and exercise interventions to improve weight loss.Increasing the intensity of the behavioural intervention significantly increased the weight reduction (WMD -2.3kg; 95% CI -1.4 to 3.3). Cognitive-behaviour therapy, when combined with a diet / exercise intervention, wasfound to increase weight loss compared with diet / exercise alone (WMD -4.9 kg; 95% CI -7.3 to 2.4). No data onmortality, morbidity or quality of life were found.

RSULTATS PRINCIPAUX : Un total de 36 tudes a rencontr les critres d'inclusion et a t inclusdans la rvision. En gnral, 3495 participants ont t valus. La majorit d'tudes a valu desstratgies de rduction de poids de comportement et de-comportement-cognitives. La thrapiecognitive, la psychothrapie, la thrapie de relaxation et hypnotherapy ont t valus dans unpetit nombre d'tudes. La thrapie de comportement a t trouve pour s'ensuivre dans de faonsignificative plus grandes rductions de poids que le placebo quand valu comme un seuld'ventaire la stratgie de perte de poids (WMD-2.5 kg; CI de 95 %-1.7 -3.3). Quand la thrapie decomportement a t combine avec un rgime / l'approche d'exercice et compare avec le rgime /l'exercice seul, l'intervention combine s'est ensuivie dans une plus grande rduction de poids. Lestudes taient htrognes pourtant la majorit d'tudes prfres en combinant la thrapie decomportement avec la dite et les interventions d'exercice pour amliorer la perte de poids.L'augmentation de l'intensit de l'intervention de comportement a de faon significative augmentla rduction de poids (WMD-2.3 kg; CI de 95 %-1.4 3.3). La thrapie de comportement cognitif,quand combin avec un rgime / l'intervention d'exercice, a t trouve pour augmenter la pertede poids compare avec le rgime / font de l'exercice seul (WMD-4.9 kg; CI de 95 %-7.3 2.4).Aucune donne sur la mortalit, le caractre morbide ou la qualit de la vie n'a t trouve.

AUTHORS' CONCLUSIONS: People who are overweight or obese benefit from psychological interventions,particularly behavioural and cognitive-behavioural strategies, to enhance weight reduction. They arepredominantly useful when combined with dietary and exercise strategies. The bulk of the evidence supportsthe use of behavioural and cognitive-behavioural strategies. Other psychological interventions are lessrigorously evaluated for their efficacy as weight loss treatments.

LES CONCLUSIONS D'AUTEURS : Les gens qui sont l'avantage obse ou obse des interventionspsychologiques, les stratgies particulirement de comportement et de-comportement-cognitives,amliorer la rduction de poids. Ils sont essentiellement utiles quand combin avec les stratgiesd'exercice et la dite. Les marchandises en vrac de l'vidence soutiennent l'utilisation de stratgiesde comportement et de-comportement-cognitives. D'autres interventions psychologiques sontmoins rigoureusement values pour leur effet comme les traitements de perte de poids.

* Meta-Analysis* Review

This version first published online: 20 April 2005 in Issue 2, 2005. Re-published online with edits: 21 January2009 in Issue 1, 2009. Last assessed as up-to-date: 29 June 2003. (Help document Dates and Statusesexplained).

Plain language summaryTRAD$$$Psychological interventions for overweight or obesitySeveral psychological methods are used to try and help people who are overweight or obese to lose weight. Thisreview found that cognitive behaviour therapy and behaviour therapy significantly improved the success ofweight loss for these people. Cognitive therapy was not effective as a weight loss treatment. There was notenough evidence to reach a conclusion about other psychological forms of therapy, such as relaxation therapyand hypnotherapy, however the evidence that is available suggests that these therapies may also be successful

in improving weight loss. No data on mortality, morbidity or quality of life were found.

Les interventions psychologiques pour le poids en excs ou la corpulencePlusieurs mthodes psychologiques sont utilises pour essayer et aider les gens qui sont obses ouobses pour maigrir. Cette rvision a constat que la thrapie de comportement cognitive et lathrapie de comportement ont de faon significative amlior le succs de perte de poids pour cesgens. La thrapie cognitive n'tait pas efficace comme un traitement de perte de poids. Il n'y avaitpas assez d'vidence pour atteindre une conclusion d'autres formes psychologiques de thrapie,comme la thrapie de relaxation et hypnotherapy, pourtant l'vidence qui est disponible suggreque ces thrapies peuvent aussi tre russies dans la perte de poids s'amliorant. Aucune donnesur la mortalit, le caractre morbide ou la qualit de la vie n'a t trouve.

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Description of the conditionObesityObesity is a condition of excess body fat (NHMRC 1997). It has been variously defined. Using body mass index(BMI = weight (kg) / height (m)2) as a measure of adiposity, in most countries obesity is defined as a BMI morethan 30, and overweight as a BMI of 25 to 30. However, measures of obesity and overweight do vary accordingto country and ethnic group (NHMRC 1997). The prevalence of obesity continues to increase in Westerncountries where approximately half of the population is currently overweight (Birmingham 1999). Bothenvironmental and biological factors have been identified which predispose individuals to becoming obese.

La corpulence est une condition de gras de corps d'excs (NHMRC 1997). Il a t de diffrentesmanires dfini. En utilisant l'index de masse de corps (BMI = le poids (le kg) / la hauteur (m) 2)comme une mesure d'adiposit, dans la plupart de corpulence de pays est dfinie comme un BMIplus de 30 et le poids en excs comme un BMI de 25 30. Pourtant, les mesures de corpulence etde poids en excs varient vraiment selon le pays et le groupe ethnique (NHMRC 1997). Laprdominance de corpulence continue augmenter dans les pays Occidentaux o l'environ moitide la population est actuellement obse (Birmingham 1999). Les facteurs tant de l'environnementque biologiques ont t identifis qui prdisposent des individus la formation obses.

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Obesity and the environment

There is no doubt that obesity is strongly influenced by environmental factors. The prevalence of obesity hasincreased rapidly in Western countries too rapidly for this to be due to biological factors alone (WHO 1998).Environmental factors which influence development of overweight and obesity are both macro-environmental(affecting the whole population) and micro-environmental (affecting the individual). Social and cultural factorsalso play a part. Anthropological studies have identified numerous changing factors which affect the prevalenceof obesity in different cultures. Throughout history humans have been active in the process of survival huntergathering, farming food, collecting fuel and participating in manufacture and commerce. The technology oftoday has reduced much of the need for human movement. These changes have occurred gradually and haveoccurred as the prevalence of obesity has increased worldwide (DHAC 2001).

Corpulence et l'environnementIl n'y a aucun doute que la corpulence est fortement sous l'influence des facteurs del'environnement. La prdominance de corpulence a augment rapidement dans les paysOccidentaux trop rapidement pour cela pour tre en raison des facteurs biologiques seuls (qui1998). Les facteurs de l'environnement qui influencent le dveloppement de poids en excs et de

corpulence sont tous les deux macro-de l'environnement (l'affectation de la population entire) etmicro-de l'environnement (l'affectation de l'individu). Les facteurs sociaux et culturels jouent aussiun rle. Les tudes anthropologiques ont identifi de nombreux facteurs changeants qui affectent laprdominance de corpulence dans de diffrentes cultures. Partout dans l'histoire les humains ontt actifs dans le processus de runion de chasseur de survivance, l'agriculture des aliments, leramassage du combustible et du fait de participer la fabrication et au commerce. La technologied'a aujourd'hui rduit une grande partie du besoin pour le mouvement humain. Ces changementsse sont produits progressivement et se sont produits comme la prdominance de corpulence aaugment dans le monde entier (DHAC 2001).

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Population activity levels have been affected by social policy and government (NHS 1993). As a result ofincreased use of motor vehicles, pedestrian safety has been compromised, reducing the use of walking andcycling as alternative forms of transportation (NHS 1993). Fewer green areas (e.g. parks and fields) within highdensity urban populations reduces the available facilities for recreational activities such as walking, ball games,skating, and cycling (WHO 1998). Modernisation has resulted in a proliferation of our food supply as well aschanging our levels of physical activity. Food supply, storage, availability, and price all determine the eatingpatterns of populations (Lester 1994). The industrialization of food production, improvements in foodpreservation techniques and the development of supermarkets, snack and ready-to-eat foods and fast foods,have altered and expanded the range of foods available in many countries. There has also been an increase insupply of foods that are high in fat (Lester 1994). High fat food consumption has increased dramatically as thesefoods are often cheaper and more readily available than healthier alternatives. Similarly, high fat junk foodsare supplied in a wider variety of settings e.g. school canteens and workplaces, increasing levels of consumptioncompared to nutritious low-fat alternatives (NHS 1993).

Les niveaux d'activit dmographiques ont t affects par la politique sociale et le gouvernement(NHS 1993). la suite de l'utilisation augmente de vhicules moteur, la scurit de piton a tcompromise, en rduisant l'utilisation de promenades pied et de cyclisme comme les formesalternatives de transport (NHS 1993). Moins de rgions 'vertes' (par ex. les parcs et les champs)

dans la haute densit les populations urbaines rduit l'quipement disponible des activits dercration comme les promenades pied, les jeux de ballon, le patinage et le cyclisme (qui 1998).La modernisation s'est ensuivie dans une prolifration de nos rserves d'aliments aussi bien que


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changement de nos niveaux d'activit physique. Les rserves d'aliments, l'entreposage, ladisponibilit et le prix tous dterminent les dessins mangeants de populations (Lester 1994).L'industrialisation de production d'aliments, les amliorations des techniques de prservationd'aliments et du dveloppement de supermarchs, casse-crote et aliments tout prts et fast-foods, a chang et a dvelopp la gamme d'aliments disponibles dans beaucoup de pays. Il y aaussi eu une augmentation dans les rserves d'aliments qui sont hauts dans le gras (Lester 1994).La haute consommation d'aliments grosse a augment radicalement comme ces aliments sont

souvent plus bon march et plus sans hsiter disponibles que les alternatives plus en bonne sant.De mme de hauts aliments 'de bazar' gros sont fournis dans une plus large varit de cadres parex. les cantines scolaires et les lieux de travail, en augmentant des niveaux de consommationcompare aux alternatives grosses-basses nutritives (NHS 1993).

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Socio-cultural factors affect food consumption. Advertising of processed, higher fat foods is more common thanadvertising for nutritious foods. This negative health message encourages the consumption of unhealthy foodsthereby negatively influencing population eating habits (Dietz 1985). Customs particular to different culturesalso affect eating habits. Celebrations often centre around the consumption of excess quantities of high-calorie,low nutritional value foods (Egger 1997). Easter tide, thanksgiving, birthday parties, weddings and Christmascelebrations are examples of such celebrations involving food in many countries. Social trends towards familieswhere parents are in the workplace rather than in the home have resulted in a reduction in time available formeal preparation with a corresponding increased consumption of convenience food and take-away food (Bryce

2001; Schneider 1997).Les facteurs Socio-culturels affectent la consommation d'aliments. La publicit d'aliments grostraits, plus hauts est plus commune que la publicit pour les aliments nutritifs. Ce message desant ngatif encourage la consommation d'aliments maladifs ainsi ngativement l'influence deshabitudes alimentaires dmographiques (Dietz 1985). Le dtail de la douane de diffrentescultures affecte aussi des habitudes alimentaires. Les clbrations centrent souvent autour de laconsommation de quantits d'excs de haute calorie, les aliments de valeur bas nutritifs (Egger1997).). La mare de Pques, thanksgiving, les soires d'anniversaire, les mariages et lesclbrations de Nol est des exemples de telles clbrations impliquant des aliments dansbeaucoup de pays. Les tendances sociales vers les familles o les parents sont dans le lieu detravail plutt que se sont la maison ensuivies dans une rduction temps disponible pour laprparation de repas avec la consommation augmente d'une correspondance d'alimentsd'avantage et d'aliments emporter (Bryce 2001; Schneider 1997).

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Biological determinants of obesityIn contrast to the environmental determinants of obesity, the biological determinants of obesity are stillincompletely understood. The pattern of inheritance of obesity strongly suggests it is a polygenic condition, withmany different genes making a small difference in effect on weight (Ravussin 2000). As a phenotype obesity isheterogeneous, with two distinct but overlapping subtypes: general obesity and abdominal obesity, each withdifferent physiological, clinical and prognostic implications. Abdominal obesity is associated with greater healthrisk than general obesity (Srensen 2001). Gender also influences development of obesity. In the majority ofprevalence studies obesity is found to be more common in women than in men. There are numerous social andbiological theories as to why this is the case. Men have higher metabolic rates and larger ratios of lean bodymass, which is more metabolically active, than women. Also, males are more likely to be physically active thanwomen. This means that men burn more calories per kilogram than women, reducing their rate of weight gain ifthey overeat. Binge eating and compulsive overeating, both of which contribute to the development of obesityin certain individuals, are more common in women than in men (French 1994). The age at which excessbodyweight develops also influences the pattern of obesity throughout the life of the individual. If obesity

develops in childhood, the risk of obesity into adulthood is increased compared to people of normal weight.Social and cultural norms regarding dietary restraint and attitudes towards overweight, acquired in childhood,influence adult behaviours and contribute to development of obesity (Power 2000). Also, because of the relativeincrease in the number of fat cells that occurs when weight is gained in childhood compared to adulthood, theobese child is predisposed to continuing obesity throughout life. In contrast, when weight is gained in adulthoodthe first adaptive change in fat cells is increase in cell lipid stores as opposed to increases in cell numbers.However, as weight continues to increase, cell numbers will increase as well as cell size (Brownell 1986b).

Dterminants biologiques de corpulence la diffrence des dterminants de l'environnement de corpulence, les dterminants biologiquesde corpulence sont toujours incompltement compris. Le dessin de succession de corpulencesuggre fortement que c'est une condition polygenic, avec beaucoup de diffrents gnes faisantune petite diffrence en fait sur le poids (Ravussin 2000). Comme une corpulence phenotype esthtrogne, avec deux sous-types distincts mais chevauchants : la corpulence gnrale et lacorpulence abdominale, chacun avec de diffrentes implications physiologiques, cliniques et

pronostiques. La corpulence abdominale est associe au plus grand risque de sant que lacorpulence gnrale (S rensen 2001). Le genre influence aussi le dveloppement de corpulence.Dans la majorit d'tudes de prdominance la corpulence est trouve pour tre plus commune


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dans les femmes que dans les hommes. Il y a de nombreuses thories sociales et biologiques quant pourquoi c'est le cas. Les hommes ont de plus hauts taux du mtabolisme et de plus grandsrapports de masse de corps mince, qui est plus metabolically actif, que les femmes. Aussi, lesmles seront mieux physiquement actifs que les femmes. Cela signifie que les hommes brlent plusde calories par kilogramme que les femmes, en rduisant leur taux de prise de poids s'ils mangent l'excs. La bringue le fait de manger l'excs mangeant et compulsif, dont les deux contribuentau dveloppement de corpulence dans de certains individus, est plus commune dans les femmes

que dans les hommes (le franais 1994). L'ge auquel l'excs bodyweight dveloppe aussi desinfluences le dessin de corpulence partout dans la vie de l'individu. Si la corpulence se dveloppedans l'enfance, le risque de corpulence dans l'ge adulte est augment compar aux gens de poidsnormal. Les normes sociales et culturelles concernant la restriction alimentaire et les attitudes versle poids en excs, acquis dans l'enfance, influencent des comportements adultes et contribuent audveloppement de corpulence (le Pouvoir 2000). Aussi, cause de l'augmentation relative dans lenombre de cellules grosses qui se produit quand le poids est gagn dans l'enfance compare l'ge adulte, l'enfant obse est prdispos la corpulence continuante partout dans la vie. Parcontraste, quand le poids est gagn dans l'ge adulte le premier changement adaptable dans lescellules grosses est l'augmentation dans la cellule lipid les magasins par opposition auxaugmentations dans les nombres de cellule. Pourtant, comme le poids continue augmenter, lesnombres de cellule augmenteront aussi bien que la grandeur de cellule (Brownell 1986b).

SHealth effects of obesityObesity contributes to the development of a number of diseases, including hypertension, hyperlipidemia,diabetes mellitus, osteoarthritis, and psychological problems (Karlsson 1997; Narbro 1997). There is also anincrease in all-cause mortality in obese people. The relationship between excess mortality and obesity is notstraightforward TRAD. It varies with factors such as age (smaller excess mortality with increasing age) (Bender1999), gender (smaller excess mortality in women than men) (Bender 1999) and level of physical fitness (Lee1999). A number of large longitudinal studies have examined the relationship between obesity, disease andmortality. In 1979, Lew and Garfinkel published the American Cancer Society study (Lew 1979). This studyfollowed 340,000 men and 420,000 women aged between 38 and 89 years for an average of 13 years. Mortalityratios (MR) were calculated for a number of conditions. Mortality ratios for obese people compared to people ofnormal weight were demonstrated to be increased for diabetes (MR 25.0), coronary disease (MR 4.0),cerebrovascular disease (MR 5.0), colon cancer (MR 1.7), prostate cancer (MR 1.3), gall bladder cancer (MR 3.6),breast cancer (MR 1.5), cervical cancer (MR 2.4), endometrial cancer (MR 5.4) and ovarian cancer (MR 1.6). Inthe Framingham study, obesity was demonstrated to be related to increased mortality and morbidity even after

controlling for diabetes, hypertension, and lipids (Hubert 1983).Hoffmans and colleagues demonstrated a U-shaped relationship between mortality and body mass index in78,000 Dutch men undergoing compulsory military examination at age 18 years and followed for 32 years. Thisrelationship was demonstrated after 20 years of follow-up. The all-cause mortality ratio between obese peopleand controls was 1.95 in this study. Smoking was not controlled for Hoffmans trial (Hoffmans 1988). Rissanenand colleagues also observed a U-shaped relationship between mortality and body mass index in their Finnishstudy of 23,000 men aged over 25 years followed for 12 years. Smoking was controlled for in this study. The all-cause mortality ratio in obese people compared to controls was 1.5 (Rissanen 1989). Manson and colleaguesreported on 116,000 United States nurses followed for eight years. The endpoints in this study were myocardialinfarction and fatal coronary events. The mortality ratio among obese women was 2.5 without controlling forsmoking, and 3.5 after adjusting for smoking (Manson 1990). Perhaps the largest study of the relationshipbetween obesity and mortality was the Norwegian Experience. This was a compulsory x-ray examination of all ofthe citizens of Norway over 15 years of age. The study, conducted between 1967 and 1975 was designed todetect tuberculosis in citizens, but weight and height were also registered. All counties except for two in Norwaywere examined. Approximately 85% of the countries population were included, a sample of 816,000 men and902,000 women. People were followed for 10 years. During this time there were 177,000 deaths. Results

demonstrated an exponential increase in all-cause mortality as body mass index increased. All-cause mortalitywas doubled in people aged 40-50 years with a body mass index of 34 (male) and 38 (female) compared tonormal weight controls (Waaler 1984).

Effets de sant de corpulenceLa corpulence contribue au dveloppement d'un certain nombre de maladies, en incluantl'hypertension, hyperlipidemia, le diabte mellitus, osteoarthritis et les problmes psychologiques(Karlsson 1997; Narbro 1997). Il y a aussi une augmentation dans la mortalit de tout-cause dansles gens obses. Le rapport entre la mortalit d'excs et la corpulence n'est pas TRAD direct. Ilvarie avec les facteurs comme l'ge (la plus petite mortalit d'excs avec l'ge augmentant) (laCintreuse 1999), le genre (la plus petite mortalit d'excs dans les femmes que les hommes) (laCintreuse 1999) et niveau de sant physique physique (le Ct sous le vent 1999). Un certainnombre de grandes tudes longitudinales ont examin le rapport entre la corpulence, la maladie etla mortalit. En 1979, Lew et Garfinkel ont publi l'tude de Socit de Cancer amricaine (Lew1979). Cette tude a suivi 340,000 hommes et 420,000 femmes ges entre 38 et 89 ans pour une

moyenne de 13 ans. Cette tude a suivi 340,000 hommes et 420,000 femmes ges entre 38 et 89ans pour une moyenne de 13 ans. Les rapports de mortalit (M.) ont t calculs pour un certainnombre de conditions. Les rapports de mortalit pour les gens obses compars aux gens de poids


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normal ont t dmontrs pour tre augments pour le diabte (M. 25.0), a maladie coronaire (M.4.0), cerebrovascular la maladie (M. 5.0), le cancer de deux-points (M. 1.7), le cancer de prostate(M. 1.3), le cancer de vsicule biliaire (M. 3.6), le cancer du sein (M. 1.5), le cancer cervical (M. 2.4),endometrial le cancer (M. 5.4) et cancer ovarien (M. 1.6). Dans l'tude de Framingham, lacorpulence a t dmontre pour tre rattache la mortalit augmente et au caractre morbidemme aprs le fait de contrler pour le diabte, l'hypertension et lipids (Hubert 1983).Hoffmans et les collgues ont dmontr un rapport U-shaped entre la mortalit et l'index de masse

de corps dans 78,000 hommes nerlandais subissant l'examen militaire obligatoire 18 annes etont suivi depuis 32 ans. Ce rapport a t dmontr aprs 20 ans de suite. Le rapport de mortalitde tout-cause entre les gens obses et les commandes tait 1.95 dans cette tude. Le tabagismen'a pas t contrl pour l'essai d'Hoffmans (Hoffmans 1988). Rissanen et les collgues ont aussiobserv un rapport U-shaped entre la mortalit et l'index de masse de corps dans leur tudefinlandaise de 23,000 hommes gs plus de 25 ans suivis depuis 12 ans. Le tabagisme a tcontrl pour dans cette tude. Le rapport de mortalit de tout-cause dans les gens obsescompars aux commandes tait 1.5 (Rissanen 1989). Manson et les collgues ont annonc sur116,000 infirmiers Amricains suivis depuis huit ans. Les points finals dans cette tude taientl'infarctus myocardial et les vnements coronaires fatals. Le rapport de mortalit parmi lesfemmes obses avait 2.5 ans sans contrler pour le tabagisme et 3.5 aprs le fait de rgler pourfumer (Manson 1990). Peut-tre la plus grande tude du rapport entre la corpulence et la mortalittait l'Exprience norvgienne. C'tait un examen de rayons X obligatoire de tous les citoyens de laNorvge plus de 15 ans d'ge. L'tude, accomplie entre 1967 et 1975 a t conue pour dcouvrir

la tuberculose dans les citoyens, mais le poids et la hauteur ont t aussi enregistrs. Tous lescomts part deux en Norvge ont t examins. Environ 85 % de la population de pays ont tinclus, un chantillon de 816,000 hommes et de 902,000 femmes. Les gens ont t suivis depuis 10ans. Pendant ce temps il y avait 177,000 morts. Les rsultats ont dmontr une augmentationexponentielle dans la mortalit de tout-cause comme l'index de masse de corps a augment. Lamortalit de tout-cause a t double dans les gens gs 40-50 ans avec un index de masse decorps de 34 (le mle) et 38 (la femelle) compare aux contrles du poids normaux (Waaler 1984).

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Description of the interventionWeight loss in obese peopleDiet, exercise and psychological strategies are potentially effective weight loss interventions in adults (NHLBI1998). Weight loss studies generally demonstrate short term weight loss (several months) only with thesestrategies, with most of the weight initially lost regained within a few years. The benefits of weight loss in obese

people have been demonstrated in short-term studies, which show reduction in cardiovascular risk factors andimproved psychological outcomes (Garrow 1988). Modest weight loss of about 10% results in improvement inblood glucose and triglycerides as well as improved physical performance and well-being. Greater loss of weightgives greater benefit (Wilding 1997). Evidence suggests that weight loss reduces blood pressure in bothoverweight hypertensive and normotensive individuals, reduces serum triglycerides and increases high-densitylipoprotein (HDL)-cholesterol, and produces some reduction in total serum cholesterol and lowdensity lipoprotein(LDL)-cholesterol. Weight loss reduces blood glucose levels in overweight and obese persons with and withoutdiabetes (Despres 1994). In obese people regular physical activity reduces rates of coronary heart disease,hypertension, non-insulin dependent diabetes mellitus even if no weight is lost (Powell 1996). Controlled studiesassessing the effect of sustained weight loss on mortality are lacking. However, some indicative information isavailable. Analysis of insurance data regarding individuals who had initially received sub-standard insurancebecause of obesity but who subsequently issued policies when they had reduced weight demonstrates amortality of weight-reduced people approaching the standard risk (Marks 1960; Metropolitan 1980). Althoughthere have been no prospective trials to show changes in mortality with weight loss in obese patients,reductions in risk factors may imply that development of type 2 diabetes mellitus and cardiovascular diseasewould be reduced with weight loss. From risk factor changes induced by spontaneous weight reductions in the

Framingham study, it has been estimated that a 10% reduction in body weight would correspond to a 20%reduction in the risk of developing coronary artery disease (Ashley 1974).

Description de l'interventionPerte de poids dans les gens obsesLe rgime, l'exercice et les stratgies psychologiques sont des interventions de perte de poidspotentiellement efficaces dans les adultes (NHLBI 1998). Les tudes de perte de poids dmontrentgnralement que la perte de poids court terme (plusieurs mois) seulement avec ces stratgies,avec la plupart du poids a au dpart perdu rcupr au cours de quelques annes. Les avantagesde perte de poids dans les gens obses ont t dmontrs dans les tudes court terme, quimontrent la rduction des facteurs de risque cardiovasculaires et ont amlior des rsultatspsychologiques (Garrow 1988). La perte de poids modeste de rsultats d'environ 10 % dansl'amlioration du glucose de sang et triglycerides aussi bien que la performance physiqueamliore et le bien-tre. La plus grande perte de poids donne le plus grand avantage (Wilding

1997). L'vidence suggre que la perte de poids rduit la tension tant dans le poids en excshypertensive que dans les individus normotensive, rduit le srum triglycerides et augmente lahaute densit lipoprotein (HDL) - le cholestrol et produit un peu de rduction du cholestrol de


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srum total et de lowdensity lipoprotein (LDL)-cholestrol. La perte de poids rduit des niveaux deglucose de sang dans les personnes obses et obses avec et sans diabte (Despres 1994). Dansl'habitu de gens obse l'activit physique rduit des taux de maladie coronarienne, hypertension,le diabte de personne charge de non-insuline mellitus mme si aucun poids n'est perdu (Powell1996). Les tudes contrles valuant l'effet de perte de poids suivie sur la mortalit manquent.Pourtant, quelques renseignements indicatifs sont disponibles. L'analyse de donnes d'assuranceconcernant les individus qui avaient au dpart reu l'assurance de qualit infrieure cause de la

corpulence, mais qui a par la suite publi des politiques quand ils avaient rduit le poids dmontreune mortalit des gens rduits de poids s'approchant du risque standard (1960 marques;Metropolitan 1980). Bien qu'il n'y ait eu aucun essai potentiel pour montrer des changements dansla mortalit avec la perte de poids dans les patients obses, les rductions des facteurs de risquepeuvent impliquer que le dveloppement de diabte du type 2 mellitus et de maladiecardiovasculaire serait rduit avec la perte de poids.Des changements de facteur de risque incits par les rductions de poids spontanes de l'tude deFramingham, il a t estim qu'une rduction de 10 % du poids de corps correspondrait unerduction de 20 % du risque de maladie d'artre coronaire se dveloppant (Ashley 1974).

TRAD$$$

Psychological aspects of obesityThere has been considerable effort to find personality variables associated with obesity, however there is noevidence that obese people differ psychologically from non-obese people. There is no difference between obeseand non-obese people in the following characteristics: degree of depression (Stewart 1983), the incidence ofpsychopathology (Friedman 1995; Stunkard 1992), social adjustment (Sallade 1973), traits of masculinity-femininity, locus of control, assertiveness TRAD and self-consciousness (Klesges 1984) and personality type(Blackmeyer 1990). However, obese people in general do not find their state desirable. For example, in asample of formerly obese people who had undergone gastric surgery, Rand and MacGregor (Rand 1991) foundthat all of the 47 participants who were interviewed would rather be deaf, dyslexic, diabetic, or suffer bad heartdisease or acne than return to being morbidly overweight. Forty-two percent preferred blindness to obesity, and43 participants would rather have a leg amputated. This dislike of obesity felt by sufferers may reflectstigmatisation by others in the population. Diverse groups hold negative stereotypes of obese people. Boysbetween six and ten years old rate silhouettes of obese boys as someone who would fight, cheat, get teasedand lie, and who was lazy, sloppy TRAD, naughty, mean, ugly, dirty and stupid (Staffieri 1967). Studies of adultattitudes similarly demonstrate negative attitudes. Adult hospital outpatients rate silhouettes of an overweightchild as less likeable than a child with a deformed leg, with a missing hand, with a facial deformity, or who was

confined to a wheelchair (Maddox 1968). Similarly, doctors and medical students hold negative views of peoplewho are obese. Medical students rate overweight women as less likeable, more emotional, and less likely tobenefit from treatment. Doctors rate overweight patients as weak-willed, ugly and awkward (Bretyspraak 1977;Maddox 1969). Job prospects are also affected. Larkin and Pines (Larkin 1979) showed that overweightcandidates were less likely to be hired, even though equally competent on job-related tests. Given thesenegative attitudes, it is surprising that obese people are not more likely to be depressed or to havepsychopathology.

Aspects psychologiques de corpulenceIl y a eu l'effort considrable de trouver des variables de personnalit associes la corpulence,pourtant il n'y a aucune vidence que les gens obses diffrent psychologiquement des gens non-obses. Il n'y a aucune diffrence entre les gens obses et non-obses dans les caractristiquessuivantes : le degr de dpression (Stewart 1983), l'incidence de psychopathology (Friedman 1995;Stunkard 1992), l'ajustage social (Sallade 1973), 'les traits' de fminit de masculinit, le lieugomtrique de contrle, le fait d'tre assur TRAD et la gne (Klesges 1984) et type de

personnalit (Blackmeyer 1990). Pourtant, les gens obses ne trouvent pas en gnral leur tatdsirable. Pourtant, les gens obses ne trouvent pas en gnral leur tat dsirable. Par exemple,dans un chantillon des gens autrefois obses qui avaient subi la chirurgie gastrique, Rand etMacGregor (Rand 1991) ont constat que tous les 47 participants qui ont t interviews seraientsourds, dyslexiques, diabtiques, ou subiraient la mauvaise maladie du cur ou l'acn que leretour tre morbidement obse. Quarante-deux pour cent ont prfr la ccit la corpulence et43 participants feraient amputer une jambe. Cette aversion de corpulence estime par les maladespeut reflter stigmatisation par d'autres dans la population. Les groupes divers tiennent desstrotypes ngatifs des gens obses. Les garons entre six et les silhouettes de taux de dix ans degarons obses comme quelqu'un qui lutterait, trichez, soyez taquins et le mensonge et qui tait

TRAD indolent, trop liquide, mchant, moyen, vilain, sale et stupide (Staffieri 1967). Les tudesd'attitudes adultes dmontrent de la mme faon des attitudes ngatives. Les silhouettes de tauxde malades externes d'hpital adultes d'un enfant obse comme moins agrable qu'un enfant avecune jambe dforme, avec une main manquante, avec une difformit du visage, ou qui a t

confin un fauteuil roulant (Maddox 1968). De mme les docteurs et les tudiants mdicauxtiennent des vues ngatives des gens qui sont obses. Les femmes de poids en excs de tauxd'tudiants mdicales comme moins agrable, plus motionnel et moins probablement profiter du


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traitement. Les patients de poids en excs de taux de docteurs comme faible-dsir, vilain etmalais (Bretyspraak 1977; Maddox 1969). Les perspectives d'emploi sont aussi affectes. Larkin etles Pins (Larkin 1979) ont montr que les candidats obses seraient moins probablement engags,mme si tout aussi comptent sur les preuves concernant l'emploi. tant donn ces attitudesngatives, il est surprenant que les gens obses ne seront pas mieux dprims ou avoirpsychopathology.

SBecause studies comparing obese and non obese persons have generally failed to find differences in globalaspects of psychological functioning, the resulting conclusion has been that obesity is not a risk factor forpsychological problems. This is at odds with clinical impression, reports from overweight people, and aconsistent literature showing strong cultural bias and negative attitudes toward obese people (Friedman 1995).It is clear that obesity confers negative consequences on both the physical and psychosocial aspects of qualityof life, especially among the severely obese. Therefore the lack of evidence supporting the existence ofpsychological morbidity in obese people is likely to be a reflection of the limitations of studies performed to daterather than an accurate reflection of the psychological well-being of individuals who are obese. Also, studieswhich demonstrate that the effects of weight loss appear to be psychologically favourable with improved self-esteem, social functioning and sense of wellness support the notion that excess weight is associated with higherlevels of psychological morbidity than normal weight (Kushner 2000).

Puisque les tudes tant comparables obse et non les personnes obses manquaientgnralement de trouver des diffrences dans les aspects globaux de fonctionnement

psychologique, la conclusion s'ensuivant a t que la corpulence n'est pas un facteur de risquepour les problmes psychologiques. C'est en dsaccord avec l'impression clinique, les rapports desgens obses et d'une littrature consquente en montrant la forte inclination culturelle et lesattitudes ngatives vers les gens obses (Friedman 1995). Il est clair que la corpulence confre desconsquences ngatives sur les aspects tant physiques que psychosociaux de qualit de la vie,surtout parmi svrement obse. Donc le manque d'vidence soutenant l'existence de caractremorbide psychologique dans les gens obses sera probablement une rflexion des restrictionsd'tudes excutes jusqu'au prsent plutt qu'une rflexion exacte du bien-tre psychologiqued'individus qui sont obses. Aussi, les tudes qui dmontrent que les effets de perte de poids ontl'air d'tre psychologiquement favorables avec l'amour propre amlior, le fonctionnement social etle sens de pleine forme soutiennent la notion que le poids d'excs est associ aux niveauxsuprieurs de caractre morbide psychologique que le poids normal (Kushner 2000).

SPsychological interventionsA variety of individual and group psychological therapies have been used in weight loss treatments. These arebriefly outlined below. Behavioural and cognitive behavioral therapies are the most commonly usedpsychological therapies for weight loss. Attitude and relationship techniques are also often utilized in designingcomprehensive psychological interventions for individualized weight loss programs. Psychotherapy is lesscommonly used (Brownell 1984).Behaviour therapy and cognitive behaviour therapy appear to be the psychological treatments of choiceinasmuch as they have been demonstrated to facilitate better maintenance of weight loss than other therapies.Behavioural treatments appear to work primarily by enhancing dietary restraint by providing adaptive dietarystrategies and by discouraging maladaptive dietary practices, and by increasing motivation to be morephysically active. Therapy aims to provide the individual with coping skills to handle various cues to overeat andto manage lapses in diet and physical activity when they occur. Treatment also provides motivation essential tomaintain adherence to a healthier lifestyle once the initial enthusiasm for the program has waned (Wing 1994).Therapeutic techniques derived from behavioural psychology include stimulus control, goal setting, and self-monitoring. They have been used for some time as adjuncts to the treatment of weight problems. When

cognitive techniques are added to behaviour therapy they appear to improve program success and reduceweight regain (Cooper 2001). These strategies are aimed at identifying and modifying aversive thinking patternsand mood states to facilitate weight loss (Wilson 1999). Interest in using cognitive behaviour therapy to achievemore modest and sustainable weight loss and improved psychological well-being is increasing.Psychodynamic therapies (therapies based on the idea that problems stem from hidden inner conflicts, e.g.psychoanalysis), humanistic therapies (therapies that focus on helping clients to find meaning in their lives andlive in ways consistent with their own values and traits, e.g. person-centred therapy) and group therapies havealso been trialled in obesity management with mixed success (Baron 1998).

Interventions psychologiquesUne varit d'individu et de groupe les thrapies psychologiques a t utilise dans les traitementsde perte de poids. Ceux-ci sont brivement exposs ci-dessous. Les thrapies de comportement etcognitives de comportement sont les thrapies psychologiques les plus utilises pour la perte depoids. L'attitude et les techniques de rapport sont aussi souvent utiliss dans la conception desinterventions psychologiques compltes pour les programmes de perte de poids individualiss. La

psychothrapie est moins communment utilise (Brownell 1984).La thrapie de comportement et la thrapie de comportement cognitive ont l'air d'tre lestraitements psychologiques de choix vu qu'ils ont t dmontrs pour faciliter la meilleure


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maintenance de perte de poids que d'autres thrapies. Les traitements de comportement ont l'airde travailler essentiellement en amliorant la restriction alimentaire en fournissant des stratgiesalimentaires adaptables et en dcourageant maladaptive les pratiques alimentaires et enaugmentant la motivation pour tre plus physiquement actifs. La thrapie a l'intention de fournir l'individu des adresses faisantes face pour manipuler des signaux diffrents pour manger l'excset diriger des dfaillances dans le rgime et l'activit physique quand ils se produisent. Letraitement fournit aussi l'objet indispensable de motivation pour maintenir l'adhrence un style

de vie plus en bonne sant ds que l'enthousiasme initial pour le programme a diminu (l'Aile1994). Les techniques thrapeutiques tires de la psychologie de comportement incluent lecontrle de stimulus, le but de mettre et le contrlant de soi. Ils ont t utiliss pour quelque tempscomme les annexes au traitement de problmes de poids. Quand les techniques cognitives sontajoutes la thrapie de comportement ils ont l'air d'amliorer le succs de programme et rduirele poids rcuprent (le Tonnelier 2001).Ces stratgies sont vises au fait d'identifier et au fait de modifier aversive les dessins pensant etles tats d'humeur pour faciliter la perte de poids (Wilson 1999). L'intrt d'utiliser la thrapie decomportement cognitive pour accomplir la perte de poids plus modeste et durable et s'est amliorle bien-tre psychologique augmente.Les thrapies de Psychodynamic (les thrapies basaient sur l'ide que les problmes proviennentdes conflits intrieurs cachs, par ex. la psychanalyse), les thrapies humanistes (les thrapies quise concentrent aider des clients trouver le sens dans leurs vies et vivant des faons en accordavec leurs propres valeurs et traits, par ex. thrapie centre de personne) et les thrapies de

groupe ont aussi t trialled dans l'administration de corpulence avec le succs mlang (le Baron1998).SGroup treatments for obesity combine therapy and education. They are widely used in commercial programmesand in self-help programs. Group treatments do not generally promote deep exploration of psychological issues.Instead they utilize social support, problem solving, and imparting information and encouragement to facilitateweight loss (Hayaki 1996). There has been limited research into group processes and testing whether groupinterventions are more or less effective than individual treatment (Hayaki 1996).There are a limited number of systematic reviews examining the effectiveness of psychological interventions foroverweight or obesity. Four systematic review examining the effectiveness of behavioural therapy havedemonstrated that behavioural therapy techniques, in combination with other weight loss approaches (diet and/ or exercise) improve weight loss (Douketis 1999, NHMRC 2003; NIH 1998; NHS CRD 1997). Systematic reviewsof other forms of psychological interventions are lacking.Les traitements de groupe pour la corpulence combinent la thrapie et l'ducation. Ils sontlargement utiliss dans les programmes commerciaux et dans les programmes d'efforts personnels.

Les traitements de groupe ne promeuvent pas gnralement d'exploration profonde d'ditionspsychologiques. Plutt ils utilisent le soutien social, la solution de problme et le fait de transmettredes renseignements et un encouragement pour faciliter la perte de poids (Hayaki 1996). L a tlimit la recherche dans les processus de groupe et la mise l'essai si les interventions de groupesont plus ou moins efficaces que le traitement individuel (Hayaki 1996).Il y a un nombre limit de rvisions systmatiques examinant l'efficacit d'interventionspsychologiques pour le poids en excs ou la corpulence. Quatre rvisions systmatiques examinantl'efficacit de thrapie de comportement a dmontr que les techniques de thrapie decomportement, dans la combinaison avec d'autres approches de perte de poids (le rgime et / oul'exercice) amliorent la perte de poids (Douketis 1999, NHMRC 2003; NIH 1998; NHS CRD 1997).Les rvisions systmatiques d'autres formes d'interventions psychologiques manquent.

S

Why it is important to do this reviewPsychological interventions ideally should be used in the context of a multi-component weight loss programmeto gain their maximum benefit. Diet and exercise combined with psychological interventions comprise anintuitively powerful weight loss program (NHLBI 1998). However, in spite of the increased comprehensiveness ofweight loss programs and improvements in patient education, understanding of the role of diet and exercise inweight loss, psychological interventions, and improved pharmacotherapies for weight reduction, results ofweight loss trials have continued to remain disappointing (Liao 2000). There are still major gaps in ourunderstanding of the roles of diet, exercise, and psychological therapies in weight reduction. Also, achievinglong-term modification of food intake and food type by the obese individual without creating decreases inenergy expenditure associated with dieting, and dealing with relapse to pre-intervention diet and exercisebehaviours are ongoing challenges (Brownell 1986). This review aimed to clarify some of these issues, usinghigh quality criteria to assess and summarise the evidence.

Pourquoi il est important de faire cette rvisionLes interventions psychologiques devraient idalement tre utilises dans le contexte d'unprogramme de perte de poids multicomposant pour gagner leur avantage maximum. Le rgime etl'exercice combin avec les interventions psychologiques comprennent un programme de perte depoids intuitivement puissant (NHLBI 1998). Pourtant, malgr la globalit augmente de


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programmes de perte de poids et d'amliorations de l'ducation patiente, la comprhension du rlede rgime et d'exercice dans la perte de poids, les interventions psychologiques, et amliorpharmacotherapies pour la rduction de poids, les rsultats d'essais de perte de poids ont continu rester dcevants (Liao 2000). Il y a des trous toujours importants dans notre comprhension desrles de rgime, exercice et thrapies psychologiques dans la rduction de poids. Aussi, enaccomplissant la modification long terme de consommation d'aliments et de type d'aliments parl'individu obse sans crer les diminutions dans la dpense d'nergie associe au fait d'tre au

rgime et s'occupant de la rechute au rgime de pr-intervention et aux comportements d'exercicesont des dfis en cours (Brownell 1986. Cette rvision a eu l'intention de clarifier certaines de cesditions, en utilisant des critres de haute qualit pour valuer et rsumer l'vidence.

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O B J E C T I V E STo assess the effects of psychological interventions for overweight or obesity as a means of achieving sustainedweight loss.

O B J E C T je V E S

valuer les effets d'interventions psychologiques pour le poids en excs ou la

corpulence comme un moyen d'accomplir la perte de poids soutenue.M E T H O D SCriteria for considering studies for this reviewTypes of studiesAll randomised controlled clinical trials of psychological interventions for weight loss in overweight or obesepeople were considered for inclusion. Quasi-randomised trials were also considered. With psychologicalinterventions it makes more sense to define duration in terms of minimum number of sessions rather thannumber of months. However, most studies report duration in terms of months. Therefore we defined trialduration according to the number of months over which they have been conducted and only included trials withinterventions that lasted longer than three months (including follow-up). Trials with a drop-out rate of greaterthan 15% were excluded.

Le M E T H O D SLes critres pour considrer les tudes pour cette rvision

Types d'tudesLes essais cliniques contrls de tout randomised d'interventions psychologiques pour la perte depoids dans les gens obses ou obses ont t considrs pour l'inclusion. Les essais de Quasi-randomised ont t aussi considrs. Avec les interventions psychologiques il a plus de sens pourdfinir la dure du point de vue du nombre minimal de sances plutt que le nombre de mois.Pourtant, la plupart des tudes signalent la dure du point de vue des mois. Donc nous avons dfinila dure d'essai selon le nombre de mois sur lesquels ils ont t accomplis et les essais seulementinclus avec les interventions qui ont dur plus longues que trois mois (en incluant la suite). Lesessais avec un taux de licenci de plus grands que 15 % ont t exclus.STypes of participantsStudies were limited to adult participants only (aged over 18 years). Studies included adults with overweight orobesity at study baseline according to any parameter (e.g. body mass index, waist measurement, waist-to-hipratio). Over the years, the diagnostic criteria and classification of obesity have changed several times (NHMRC1997). To be consistent with changes in classification and diagnostic criteria of obesity through the years, the

diagnosis needed to have been established using the standard criteria valid at the time of the beginning of thetrial. Changes in diagnostic criteria were considered for exploration in sensitivity analyses.

Types de participantsLes tudes ont t limites aux participants adultes seulement (g plus de 18 ans). Les tudes ontinclus des adultes avec le poids en excs ou la corpulence la ligne des bases d'tude selonn'importe quel paramtre (par ex. l'index de masse de corps, la mesure de taille, le rapport detaille--gratte-cul). Au cours des ans, les critres diagnostiques et la classification de corpulenceont chang plusieurs fois (NHMRC 1997). Pour tre en accord avec les changements dans laclassification et les critres diagnostiques de corpulence toutes les annes, la diagnose devait avoirt tablie en utilisant les critres standard valides au moment du dbut de l'essai. Leschangements dans les critres diagnostiques ont t considrs pour l'exploration dans lesanalyses de sensibilit.S

Types of interventionsStudies that stated they included a psychological intervention were not included within the analyses unless thetype of psychological intervention was able to be identified. Individual and group therapies were included. All


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types of psychological interventions were considered for inclusion.It is common for psychological interventions to be prescribed in conjunction with dietary and exerciseinterventions. The analysis included the following subcategories: psychological intervention versus no treatment; psychological intervention versus different type of psychological intervention; psychological intervention plus diet and / or exercise versus control plus diet and/ or exercise.Studies which combined a pharmacological intervention with a psychological intervention were excluded fromanalysis as the effect of the pharmacological intervention on weight could outweigh the effect of the

psychological intervention.

Types d'interventionsLes tudes qui ont dclar qu'ils ont inclus une intervention psychologique n'ont pas t inclusesdans les analyses moins que le type d'intervention psychologique ne soit capable d'tre identifi.L'individu et les thrapies de groupe ont t inclus. Tous les types d'interventions psychologiquesont t considrs pour l'inclusion.C'est commun pour les interventions psychologiques tre prescrites dans la conjonction avec lesinterventions d'exercice et la dite. L'analyse a inclus les sous-catgories suivantes : l'intervention psychologique contre aucun traitement; l'intervention psychologique contre le diffrent type d'intervention psychologique; l'intervention psychologique plus le rgime et / ou l'exercice contre le contrle plus le rgime et /

ou l'exercice.Les tudes qui ont combin une intervention pharmacologique avec une intervention psychologique

ont t exclues de l'analyse comme l'effet de l'intervention pharmacologique sur le poids pourraitemporter sur l'effet de l'intervention psychologique.

STypes of outcome measures

Primary outcomes weight or another indicator of body mass (e.g. body mass index, waist measurement, waist-to-hip ratio); morbidity (e.g. diabetes, cardiovascular disease, osteoarthritis) and mortality (e.g. death from myocardialinfarction, stroke); well-being and quality of life measures (ideally, measured using a validated instrument, e.g. SF36 Quality ofLife Measure).Secondary outcomes cost of implementing the psychological intervention; measured psychological functioning (ideally, measured using a validated instrument e.g. Hamilton DepressionRating Scale);

fasting plasma glucose and HbA1c; plasma triglycerides, high-density lipoprotein, low-density lipoprotein and very-low-density lipoprotein ; adverse effects.Spedific effect modifiers compliance.Timing of outcome measurementWeight loss or change in an outcome measure of weight was assessed in studies less than 12 months durationand studies greater than 12 months duration.

Types de mesures de rsultatRsultats primaires le poids ou un autre indicateur de masse de corps (par ex. l'index de masse de corps, la mesurede taille, le rapport de taille--gratte-cul); le caractre morbide (par ex. le diabte, la maladie cardiovasculaire, osteoarthritis) et la mortalit(par ex. la mort de l'infarctus myocardial, le coup);

le bien-tre et les mesures de qualit de la vie (idalement, l'utilisation mesure d'un instrumentvalid, par ex. Mesure de Qualit de la vie de SF36).

Rsultats secondaires le prix d'excuter l'intervention psychologique; a mesur le fonctionnement psychologique (idalement, l'utilisation mesure d'un instrumentvalid par ex. Hamilton Depression valuant l'chelle); le jene du glucose de plasma et de HbA1c; le plasma triglycerides, la haute densit lipoprotein, la densit basse lipoprotein et "la densit trsbasse" lipoprotein; effets hostiles.

Spedific effectuent des modificateurs

acquiescement.

Choix du moment de mesure de rsultat


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La perte de poids ou le changement dans une mesure de rsultat de poids ont t valus dans lestudes dure de moins de 12 mois et tudes plus grandes que dure de 12 mois.

S

Search methods for identification of studiesElectronic searchesThe following electronic databases were searched: The Cochrane Library Issue 1 2003 (including the Cochrane Controlled Trials Register (CCTR)); MEDLINE (June 2003); PsychInfo (June 2003); PsychLit (June 2003); Embase (June 2003).Databases of ongoing trials were searched, including Current Controlled Trials (www.controlled-trials.com) andthe National Research Register s(www.update-software.com/National/nrr-frame.html).For a detailed search strategy see Appendix 1.Additional key words of relevance were sought during the electronic or other searches. None were identified.Publications in all languages were sought.

Fouillez des mthodes pour l'identification d'tudesRecherches lectroniquesLes bases de donnes lectroniques suivantes ont t fouilles : l'dition de Bibliothque Cochrane 1 2003 (en incluant le Cochrane le Registre d'Essais Contrl(CCTR)); MEDLINE (juin de 2003); PsychInfo (juin de 2003); PsychLit (juin de 2003); Embase (juin de 2003).Les bases de donnes d'essais en cours ont t fouilles, en incluant des Essais Contrls Actuels(www.controlled-trials.com) et le Registre de Recherche national s (www.update-software.com/National/nrr-frame.html).Pour une recherche dtaille la stratgie voir l'Appendice 1.Les mots cl supplmentaires de pertinence ont t cherchs pendant les recherches lectroniquesou autres. Personne n'tait identified. Les publications dans toutes les langues ont t cherches.

S

Searching other resourcesThe reference list of review articles and of all included studies were searched in order to find other potentiallyeligible studies. Potential missing and unpublished studies were planned to be sought by contacting experts inthe field. This was not necessary.

Recherche d'autres ressourcesLa liste de rfrence d'articles de rvision et de toutes les tudes incluses a t fouille pour findd'autres tudes potentiellement ligibles. Les disparus de potentiel et les tudes non publies ontt planifis pour tre cherchs en contactant des experts en eld. Ce n'tait pas ncessaire.SData collection and analysisSelection of studiesAssessment of quality and results data were undertaken by three reviewers (KS, POR and JK). Full articles wereretrieved for further assessment if the information given suggested that the study: 1. Included people who were

overweight or obese; 2. Compared a psychological intervention with placebo or another psychologicalintervention; 3. Assessed one or more relevant clinical outcome measures; 4. Used random allocation to thecomparison groups. When a title / abstract could not be rejected with certainty, the full text of the article wasobtained for further evaluation. Interrater agreement for study selection was measured using the kappa statistic(Cohen 1960). Where differences in opinion existed, these were resolved by a third party (CDM).

Collecte de donnes et analyseSlection d'tudesL'valuation de qualit et de donnes de rsultats a t entreprise par trois critiques (KS, POR et

JK). Les articles complets ont t rcuprs pour l'valuation de plus si les renseignements donnsont suggr que l'tude : 1. Les gens inclus qui taient obses ou obses; 2. Compar uneintervention psychologique avec le placebo ou une autre intervention psychologique; 3. valu ouplus de mesures de rsultat cliniques pertinentes; 4. Allocation au hasard utilise aux groupes decomparaison. Quand un titre / le rsum ne pouvait pas tre rejet avec la certitude, le texte entierde l'article a t obtenu pour l'valuation de plus. L'accord d'Interrater pour la slection d'tude at mesur en utilisant le statistique kappa (Cohen 1960). O les diffrences l'opinion ont exist,ceux-ci ont t rsolus par une tierce personne (CDM).


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SData extraction and managementData extracted included the following: general information: Published/unpublished, title, authors, source, contact address, country, language ofpublication, year of publication, duplicate publications; trial characteristics: Design, duration, randomisation (and method), allocation concealment (and method),blinding (outcome assessors), check of blinding; intervention: Psychological prescription, comparison interventions (method, timing); patients: Sampling (random/convenience), exclusion criteria, total number and number in comparison groups,gender, age, diagnostic criteria of overweight/obesity, similarity of groups at baseline, assessment ofcompliance/relapse, withdrawals/losses to follow-up (reasons/description), subgroups; outcomes: Outcomes specified above, what was the main outcome assessed in the study, other events, lengthof follow-up. results: For outcomes and times of assessment, intention-to-treat analysis.A template data extraction form was developed and sent to the Metabolic and Endocrine Disorders GroupEditorial Base for approval. Study authors were not contacted for further information.

Extraction de donnes et administrationLes donnes ont extrait a inclus la chose suivante : renseignements gnraux : Publi/non publi, le titre, les auteurs, la source, contactent l'adresse,le pays, la langue de publication, l'anne de publication, copient des publications; caractristiques d'essai : le Design, la dure, randomisation (et la mthode), l'action de cacherd'allocation (et la mthode), en aveuglant (les assesseurs de rsultat), le chque d'aveuglement; intervention : la prescription psychologique, les interventions de comparaison (la mthode, en

prvoyant); patients : en Essayant (au hasard / l'avantage), les critres d'exclusion, le nombre total et lenombre dans les groupes de comparaison, le genre, l'ge, les critres diagnostiques de poids enexcs/corpulence, la similarit de groupes la ligne des bases, l'valuationd'acquiescement/rechute, les retraits/pertes la suite (les raisons/description), les sous-groupes; rsultats : les Rsultats specified au-dessus, ce qui tait le rsultat principal valu dans l'tude,d'autres vnements, la longueur de suite. rsultats : Pour les rsultats et les temps d'valuation, analyse d'intention--plaisir.Une forme d'extraction de donnes de gabarit a t dveloppe et envoye la Base d'ditorial deGroupe de Dsordres du Mtabolisme et Endocrine pour l'approbation. On n'a pas contactd'auteurs d'tude pour les renseignements de plus.

SAssessment of risk of bias in included studiesThe methodological quality of reporting each trial was be assessed based largely on the quality criteria specifiedby Schulz and by Jadad (Jadad 1996; Schulz 1995). In particular, the following factors was studied:1. Minimisation of selection bias a) was the randomisation procedure adequate? b) was the allocationconcealment adequate?2. Minimisation of attrition bias a) were withdrawals and dropouts completely described? b) was analysis byintention-totreat?3. Minimisation of detection bias were outcome assessors blind to the intervention?Based on these criteria, studies were subdivided into the following three categories (see Cochrane Handbook):A all quality criteria met: low risk of bias.B one or more of the quality criteria only partly met: moderate risk of bias.C one or more criteria not met: high risk of bias.This classification was planned to be used as the basis of a sensitivity analysis.Each trial was assessed for quality assessment independently by two reviewers (KS, JK). Interrater agreementwas calculated using the kappa statistic.

L'valuation de risque d'inclination dans les tudes inclusesLa qualit mthodologique de signaler chaque essai tait tre value base grandement sur lescritres de qualit specified par Schulz et par Jadad (Jadad 1996; Schulz 1995). En particulier, lesfacteurs suivants a t tudi :1. Minimisation de slection influent sur a) la procdure randomisation tait adquate ? b) l'actionde cacher d'allocation tait adquat ?2. Minimisation d'usure influent sur a) les retraits et les licencis ont-ils t compltement dcrits ?b) tait l'analyse par l'intention-totreat ?

3. Minimisation d'inclination de dtection les assesseurs de rsultat taient aveugles l'intervention ?Bas sur ces critres, les tudes ont t subdivises dans les trois catgories suivantes (voir leManuel Cochrane) :A Tous les critres de qualit se sont rencontrs : bas le risque d'inclination.

B un ou plus de critres de qualit s'est seulement partiellement rencontr : modrez le risqued'inclination.C un ou plusieurs critres non rencontrs : haut le risque d'inclination.


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Ce classification a t planifi pour tre utilis comme la base d'une analyse de sensibilit. Chaqueessai a t valu pour l'valuation de qualit de faon indpendante par deux critiques (KS, JK).L'accord d'Interrater a t calcul en utilisant le statistique kappa.S

Data synthesisData were entered into the Cochrane Review Manager (RevMan) software. Both random and fixed effectsmodels were used to pool data. Effect sizes are presented as weighted mean differences with 95% confidenceintervals. We had planned to express results of dichotomous variables as Mantel Haenszel odds ratios (OR) with95% confidence intervals. The chi-square method was used to assess heterogeneity with the significance set atP


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La mise l'essai de la robustesse des rsultats en rptant l'analyse en utilisant de diffrentesmesures de grandeur d'effets (la diffrence de risque, le rapport de cote etc.) et les diffrentsmodles statistiques ( xed et les modles d'effets au hasard) a t planifie.

SR E S U L T SDescription of studiesSee: Characteristics of included studies; Characteristics of excluded studies.Results of the searchThe search strategy identified 3607 abstracts for perusal. On review of the abstracts, 454 articles were retrievedfor perusal. Of these, 56 potentially relevant trials were located. Three further trials were found throughhandsearching of reference lists, yielding 59 potentially relevant trials (Figure 1).

R E S U L T SDescription d'tudesVoir : Caractristiques d'tudes incluses; Caractristiques d'tudes exclues.

Rsultats de la rechercheLa stratgie de recherche identified 3607 rsums pour la lecture attentive. Sur la rvision desrsums, 454 articles ont t rcuprs pour la lecture attentive. De ceux-ci, 56 essais

potentiellement pertinents ont t trouvs. Trois essais de plus ont t trouvs par handsearchingde listes de rfrence, en produisant 59 essais potentiellement pertinents (Figure 1).SFigure 1. Study flow diagram

A total of 36 studies met the inclusion criteria and were included in the review. The kappa statistic for trialselection was 0.75; confidence bounds 0.63 to 0.88.Included studiesThe details of these studies are described in the table Characteristics of included studies.A number of trials did not present results in a manner that enabled variance data for change in outcomemeasures to be extracted. However, the studies met all of the inclusion criteria outlined above. Therefore thesestudies, identified in the Notes section of the Characteristics of included studies table, are included in theresults but are reported narratively (Agras 1995; Block 1980; Calle-Pascual 1992; Castro 1983; Chapman 1978;Foreyt 1973; Goodrick 1998; Hagen 1974; Jeffery 1983; Kirschenbaum 1985; Stuart 1971; Wollersheim 1970).The data from this group of studies are not included in the analyses.The trials were conducted between 1970 and 2001 and varied in size from 6 to 1191 participants. Overall, 3495

participants were evaluated. The trials varied in length (including follow-up) from 12 weeks to 156 weeks. Thirtyof the 36 trials were longer than 16 weeks duration.All included studies were randomized controlled trials. Two studies were factorial in design (Burnett 1985; Jeffery1983), and the remaining 34 were parallel. Randomization was from stratified blocks, mainly according topercentage overweight, in 13 studies.

Le chiffre 1. tudiez le diagramme de flowUn total de 36 tudes a rencontr les critres d'inclusion et a t inclus dans la rvision. Lestatistique kappa pour la slection d'essai tait 0.75; confidence limite 0.63 0.88.

tudes inclusesLes dtails de ces tudes sont dcrits dans les Caractristiques de table d'tudes incluses.Un certain nombre d'essais n'ont pas prsent de rsultats dans une manire qui a permis auxdonnes de dsaccord pour le changement dans les mesures de rsultat d'tre extraites. Pourtant,

les tudes ont rencontr tous les critres d'inclusion exposs au-dessus. Donc ces tudes, identifieddans la section 'de Notes' des Caractristiques de table d'tudes incluse, sont incluses dans lesrsultats, mais sont annonces narratively (Agras 1995; Block 1980; Calle-Pascual 1992; Castro1983; Chapman 1978; Foreyt 1973; Goodrick 1998; Hagen 1974; Jeffery 1983; Kirschenbaum 1985;Stuart 1971; Wollersheim 1970).Les donnes de ce groupe d'tudes ne sont pas incluses dans les analyses.Les essais ont t accomplis entre 1970 et 2001 et ont vari dans la grandeur de 6 1191participants. En gnral, 3495 participants ont t valus. Les essais varis de longueur (enincluant la suite) de 12 semaines 156 semaines. Trente des 36 essais taient plus longs que durede 16 semaines.

Toutes les tudes incluses taient des essais contrls de randomized. Deux tudes taient factorialdans le design (Burnett 1985; 1983 de Jeffery) et la conservation 34 taient parallles.Randomization tait des blocs de stratified, surtout selon le poids en excs en pourcentage, dans13 tudes.

SParticipants and settingThere were a total of 3495 participants in the 36 trials. All trials were conducted in adults. The weighted mean


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age of participants was 43.1 years for the 18 trials that reported age as a mean value. The remaining 18 trials,which reported age as a range, included participants aged between 16 and 75 years. Two trials included menonly, 14 included women only, and 20 included both men and women. Across these 20 trials, 25% ofparticipants were male.Twenty-nine studies were conducted in the United States of America, and one was conducted in The Netherlands(Nauta 2000), Canada (Cochrane 1985), Spain (Calle-Pascual 1992), Colombia (Castro 1983), the UnitedKingdom (Oldroyd 2001), Sweden (Lindahl 1999) and Switzerland (Painot 2001) respectively. All studies wereoutpatient community studies except for one study which was an inpatient hospital study (Lindahl 1999). The

range of outpatient settings in which trials were conducted included general medical clinics, hospital obesityoutpatient clinics, primary care, university campuses and workplace settings. Most participants were recruitedby local news media (e.g. local newspaper, radio announcements, bulletin boards) and physician referrals. Onestudy recruited their sample from a database of participants rejected from participating in a cohort study(Jeffery 1983), one from a group of US Navy personnel deployed on a combatant ship of the US Navy (Dennis1999), and one from a database of respondents to a community survey questionnaire (Lindahl 1999). Thepsychological interventions that were evaluated are listed below and discussed in more detail in the resultssection. Twenty-five trials evaluated multiple psychological interventions within their design, and 11 trialsevaluated a single psychological intervention.Thirty studies evaluated a behavioral intervention, four evaluated a cognitive behavioral intervention, fourevaluated a relaxation intervention, two evaluated a cognitive intervention, one evaluated a psychotherapeuticintervention, and one evaluated a hypnotherapy intervention.Studies did differ in the types of interventions evaluated: Ten trials evaluated behaviour therapy compared withno treatment for weight loss (Foreyt 1973; Goodrick 1998; Hagen 1974; Israel 1979; Jeffery 1995; Oldroyd 2001;Rozensky 1976; Saccone 1978; Stevens 2001; Wollersheim 1970),

Seventeen trials compared more intensive with less intensive behaviour therapy (Black 1983; Black 1984;Brownell 1978a; Burnett 1985; Carroll 1981; Castro 1983; Chapman 1978; Hagen 1974; Israel 1979; Jeffery1983; Jeffery 1995; Johnson 1979; Kirschenbaum 1985; Rozensky 1976; Saccone 1978; Wing 1991; Wing 1996), Eight trials compared behaviour therapy in combination with diet / exercise with diet / exercise alone (Black1984; Calle-Pascual 1992; Gormally 1981; Jeffery 1985; Lindahl 1999; Stuart 1971; Wing 1984; Wing 1985), Three trials compared behaviour therapy with cognitive therapy (Goodrick 1998; Nauta 2000; Wollersheim1970), Two trials compared cognitive behaviour therapy + diet / exercise with diet / exercise alone (Block 1980;Dennis 1999), and One trial each compared:hypnotherapy with no treatment (Cochrane 1985);relaxation therapy with no treatment (Block 1980);cognitive behaviour therapy with no treatment (Agras 1995),and behaviour therapy (Sbrocco 1999);cognitive therapy with no treatment (Goodrick 1998);cognitive behaviour therapy and diet / exercise with diet / exercise (Painot 2001) respectively.

Participants et cadre

Il y avait un total de 3495 participants aux 36 essais. Tous les essais ont taccomplis dans les adultes. L'ge moyen pondr de participants tait 43.1 anspour les 18 essais qui ont signal l'ge comme une valeur moyenne.

S

Ootcome measuresThe degree of overweight in the patient groups and the types of outcome measures reported did not differmarkedly between groups. Most reported weight change as kilograms or pounds lost. Studies also reportedweight loss according to change in BMI, change in waist circumference or waist-hip ratio, or change inpercentage overweight.

Weight entry criteria for most studies included participants who were overweight as well as participants withobesity. Four studies specified weight entry criteria according to BMI (in excess of 27 for three studies and BMImore than 30 for one study). Nineteen studies specified weight entry criteria according to percentageoverweight according to Metropolitan Life Insurance Tables. The weighted mean % overweight of participants inthese studies was 43.3% (range 27 to 75%). Six studies specified weight entry according to pounds / kilogramsoverweight. The weighted mean kilograms overweight of participants in these studies was 11.6 kg (range =11.4 to 18.8 kg). Six studies did not specify weight entry criteria but did specify baseline weight data forparticipants.

Two trials were weight loss interventions in participants with noninsulin dependent diabetes mellitus (Calle-Pascual 1992; Wing 1985), two trials were interventions in participants with impaired glucose tolerance (Lindahl1999; Oldroyd 2001), two were interventions in participants with binge eating disorder (Agras 1995; Goodrick1998), one was an intervention in US Naval personnel on deployment (Dennis 1999), and one was anintervention in participants with mild hypertension (Stevens 2001).

Frequency of sessions ranged from daily to monthly. The duration of the interventions ranged from four weeks to

12 months. The median duration of the interventions was 12 weeks. Follow-up time post intervention rangedfrom three months to 36 months. The weighted mean total trial length was 18.6 months (range 3 to 36 months).


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Secondary outcome measures recorded included haematological measures e.g. serum glucose, lipids, HbA1c,blood pressure and measures of dietary intake and exercise performance.

None of the trials included the main outcomes of mortality (total or specific), morbidity, quality of life measures,well-being or the additional outcome costs of implementing the intervention.

Excluded studiesFollowing an evaluation of the methods section of the trials, 23 trials were excluded from the review. These

studies and their reasons for exclusion are presented in Characteristics of excluded studies.Risk of bias in included studiesThe methodological quality of included studies is described in the Characteristics of included studies table. Thekappa statistic and confidence intervals for methodological quality of included studies was 0.88 (0.80 to 0.95).All 36 of the reported studies had some methodological weaknesses according to the quality criteria applied.Only two studies (Black 1983; Oldroyd 2001) reported the method of randomization. For the remaining 34studies it was not possible to tell whether allocation to groups was concealed. All included studies had a loss tofollow-up of 15% or less, as specified in the inclusion criteria for the review. In all but one study (Oldroyd 2001),blinding of investigators to outcomes was not clear or not done. The duration of all included studies, includingfollow-up, was three months or more, as specified in the inclusion criteria for the review. Six of the 36 trials were16 weeks or less in duration.The results of three studies could not be extrapolated to other populations due to substantial selection bias(Dennis 1999; Jeffery 1983; Lindahl 1999).Many studies had small sample sizes, meaning that it would have been difficult to detect small but potentiallysignificant differences across groups. Three studies were analysed by intention to treat (Nauta 2000; Oldroyd2001; Stuart 1971). All other studies were analysed by treatment received.

One study was categorised as A, indicating that all criteria were met (Oldroyd 2001). All other studies werecategorised as B, indicating that one or more criteria were not met. All studies had a drop-out rate of 15% orless, as specified in the inclusion criteria for study selection.

Effects of interventions The studies included in this review evaluate a number of psychological interventions in participants withoverweight and obesity. The only outcome measured and used in the analyses was weight. BMI, blood pressure,serum cholesterol, serum triglycerides, fasting serum glucose and serum high density lipoprotein cholesterol(HDL) data were insufficient for analyses to be performed. Quantification of the effect of heterogeniety wasassessed by means of I2 , ranging from 0 to 100% including its 95% confidence interval (Higgins 2002). Isquared demonstrates the percentage of total variation across studies due to heterogeneity and is used to judgethe consistency of evidence.

Behaviour therapy versus no treatment controlTen studies contained groups that compared behaviour therapy to control as a weight loss intervention inparticipants with overweight or obesity (Foreyt 1973; Goodrick 1998; Hagen 1974; Israel 1979; Jeffery 1995;

Oldroyd 2001; Rozensky 1976; Saccone 1978; Stevens 2001; Wollersheim 1970). Behavioral therapies evaluatedincluded self-control and therapist-controlled contingencies (Israel 1979; Jeffery 1995; Rozensky 1976), stimuluscontrol (Goodrick 1998; Israel 1979; Saccone 1978; Stevens 2001), reinforcement (Israel 1979; Saccone 1978),stages of change model of behaviour therapy (Oldroyd 2001), self-monitoring (Goodrick 1998; Jeffery 1995),problem solving and goal setting (Goodrick 1998), covert sensitization (Foreyt 1973) and behaviour modification(Hagen 1974; Wollersheim 1970). The frequency of clinical contact ranged from weekly to monthly sessionslasting 15 to 90 minutes. The median frequency of clinical contact was fortnightly sessions lasting 60 minutes.The duration of intervention ranged from 7 to 78 weeks. Median duration of intervention was 12 weeks.

Category 1: Weight change in kilogramsFour studies included data comparing behaviour therapy with control for weight loss that were not suitable formeta-analysis (Foreyt 1973; Goodrick 1998; Hagen 1974; Wollersheim 1970). These studies reported weight lossbefore versus after psychological intervention. Mean weight losses were reported for each study however novariance data were available for these studies. The range of weight change in participants who participated inbehavioral interventions was -0.6 kg to -5.5 kg after the behavioral intervention. The range in participants whoacted as no treatment controls was -2.8 kg to + 1.8 kg. In all studies, participants who participated in the

behavioral intervention lost more weight than no treatment controls.Six studies, involving 1458 participants, included data regarding weight loss that were suitable for meta-analysis(Israel 1979; Jeffery 1995; Oldroyd 2001; Rozensky 1976; Saccone 1978; Stevens 2001). Data were analysedaccording to two time frames, studies with a duration of 12 months or less and studies with a duration of morethan 12 months.Five studies included data for duration of less than 12 months. All studies favoured behaviour therapy againstno treatment control for weight loss. Significant heterogeneity between studies was present (P < 0.00001).When heterogeneity was re-assessed excluding data from Stevens 2001, which had much smaller variance thanthe other studies, the results of the Chi-squared test were P > 0.06. Participants who participated in behavioralweight loss programmes lost 2.5 kg (95% confidence interval 1.7 to 3.3) more weight than no treatment controls(P < 0.01).Two studies included data for duration of greater than 12 months (Jeffery 1995; Stevens 2001). Data fromJeffery, 1995 were collected at 30 months and data from Stevens, 2001 were collected at 36 months. Bothstudies favoured behaviour therapy against no treatment control for weight loss. Studies were homogeneous forthe outcome of interest (P = 0.81). Participants who participated in behavioral weight loss programs lost 2 kg(95% confidence interval 2.7 to 1.3) more than no treatment controls (P < 0.01).

Category 2: Additional outcome measuresTwo studies (Oldroyd 2001; Stevens 2001) reported change in blood pressure data at conclusion of the study.


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Data were unable to be compared statistically therefore analysis was not performed. Both studies demonstrateda fall in systolic and diastolic blood pressure with weight loss. The study by Oldroyd 2001 found no significantchange in fasting serum glucose or fasting serum cholesterol between intervention and control groups howeverfasting serum insulin was improved in the intervention compared with control group.

Behaviour therapy with diet / exercise versus diet /exerciseEight studies contained groups that compared behaviour therapy in combination with diet / exercise with diet /exercise alone as a weight loss intervention in participants with overweight or obesity (Black 1984; Calle-Pascual

1992; Gormally 1981; Jeffery 1985; Lindahl 1999; Stuart 1971; Wing 1984; Wing 1985). Three studies reportedsignificant improvement in weight loss with the addition of behaviour therapy to the diet / exercise intervention(Gormally 1981, Wing 1985, Lindahl 1999). Behavioral therapies evaluated included self-control and therapist-controlled contingencies (Black 1984; Jeffery 1985; Wing 1985), stimulus control (Calle-Pascual 1992; Gormally1981; Stuart 1971; Wing 1985), reinforcement (Gormally 1981; Wing 1984), self-monitoring (Black 1984;Gormally 1981), problem solving and goal setting (Gormally 1981; Jeffery 1985; Lindahl 1999), and behaviourmodification (Calle-Pascual 1992; Gormally 1981). The frequency of clinical contact ranged from second daily tomonthly sessions lasting 40 to 180 minutes. The median frequency of clinical contact was fortnightly sessionslasting 60 minutes. The duration of intervention ranged from 1 to 26 weeks. Median duration of intervention was12 weeks. The concomitant interventions were low calorie diet (Calle-Pascual 1992; Gormally 1981; Jeffery1985; Lindahl 1999; Stuart 1971; Wing 1984; Wing 1985), nutritious balanced diet (Black 1984), instructions togradually increase levels of physical activity (Black 1984; Gormally 1981; Jeffery 1985), daily low to moderatephysical activity for 2.5 hours (Lindahl 1999), and individualised aerobics exercise programme based uponwalking further during daily activities (Stuart 1971).

Category 1: Weight change in kilograms

Two studies included data comparing behaviour therapy in combination with diet / exercise with diet / exercisealone for weight loss that were not suitable for meta-analysis (Calle-Pascual 1992; Stuart 1971). These studiesreported weight loss before versus after psychological intervention. Mean weight loss was reported however novariance data were available for the studies. The mean weight change in participants who participated in thebehavioral intervention was a loss of 10 kg after the behavioral intervention. The change in participants whoacted as no treatment controls was a mean gain of 0.5 kg.Six studies, involving 467 participants, included data regarding weight loss that were suitable for meta-analysis(Black 1984; Gormally 1981; Jeffery 1985; Lindahl 1999; Wing 1984; Wing 1985). Data were analysed accordingto time frame. No study included data with a duration of more than 12 months.Five studies favoured behaviour therapy in combination with diet and exercise and one study favoured diet andexercise alone for weight loss. Significant heterogeneity between studies was present (P < 0.01). These datacome from multiple studies and different populations which may be the factors contributing to the significantstatistical heterogeneity present, and limit the reliability of the results.

Category 2: Additional outcome measures The study by Lindahl 1999 reported change in blood pressure data at conclusion of the study. Results

demonstrated a fall in systolic and diastolic blood pressure with weight loss in both intervention and controlgroups. Total serum cholesterol, triglycerides and fasting plasma glucose also fell in both intervention andcontrol groups. In the study by Wing 1985, participants in both the intervention and control groups experiencednon-significant improvements in fasting blood sugar, serum triglycerides, serum cholesterol, and systolic bloodpressure, and significant improvement in HDL cholesterol. The study by Calle-Pascual 1992 demonstrated asignificant improvement in fasting serum glucose, systolic blood pressure, diastolic blood pressure, serumtriglyceride level, and HDL cholesterol level in the intervention group compared with the control group.

More intensive versus less intensive behaviour therapySeventeen studies contained groups that compared more intensive with less intensive behaviour therapies as aweight loss intervention in participants with overweight or obesity (Black 1983;

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