Physiotherapy September 2001/vol 86/no 9

503

ON reading the article by Foster et al inthe April edition of Physiotherapy(Critically Appraised Topics) I wasinitially confused by the use of thestatistics in box 2, especially theabsolute risk reduction and relativerisk reduction. It seemed counter-intuitive that a treatment (in this case,intermittent cervical traction) whichworsened the outcome of theexperimental group was given apositive value for relative riskreduction.

Following correspondence with theauthors, I was referred back to Sackettet al’s original article (1998). The moreI read his original work, the more Idoubt the use of the statistical tests inFoster et al’s work.

Dr Sackett makes it plain that riskreduction measures are relevant to the‘occurrence of adverse outcomes inactive therapy’. Furthermore, the‘number needed to treat’ or NNT isdefined in terms of ‘the number ofpatients a clinician needs to treat inorder to prevent one additionaladverse reaction’. It seems logical toanalyse an intervention which worsensoutcome (as in the intermittenttraction example) using the calculation

for numbers needed to harm (NNH).I do not have the advantage of an

MSc or a PhD, and I cannot pretend tobe an expert on statistics. However, thearticle was written to help practisingclinicians like myself to use EBM in away which is relevant to our clinicalwork. I am not convinced that usingthese calculations in the way suggestedby the article will achieve this aim. Areany statisticians reading this able tooffer an opinion?

Peter Gladwell MCSP BScBristol

References

Foster, N, Barlas, P, Chesterton, L andWong, J (2001). ‘Critically appraisedtopics (CATS): One method offacilitating evidence-based practice inphysiotherapy’, Physiotherapy, 87, 4, 179-190.

Sackett, D L and Straus, S E for Firm Aof the Nuffield Department ofMedicine (1998). ‘Finding andapplying evidence during clinicalrounds: The "Evidence Cart"’, Journalof the American Medical Association, 280,1336-38.

‘The Simplest Statistic’

Letters

Cooksey andCawthorne –Medical ConsultantsIN the article ‘Clinical outcomes ofvestibular rehabilitation’ in the Julyissue of Physiotherapy the reference toDr Cooksey’s occupation was incorrect.

In the 1940s Dr Frank Cooksey OBEwas the consultant in physical medicineat King’s College Hospital, DenmarkHill, London, and Mr TerenceCawthorne (later Sir TerenceCawthorne) was consultant in the ENT department in the same hospital.Dr Cooksey was still on the staff in the1950s.

The papers given to the RoyalSociety of Medicine (Cawthorne, 1945;Cooksey, 1945) refer to exercises beingshown to the audience by twophysiotherapists on Dr Cooksey’s staff,Miss Swan and Miss Hudson.

I was a student in 1956-59 at King’sCollege Hospital School ofPhysiotherapy and in our final termsupervised the ‘head class’ for patientsrecovering from fenestrationoperations being performed by Mr Cawthorne and his team. I hopethis helps to set the record straight.

Barbara KelsallMCSPStevenage

References

Cawthorne, T (1945). ‘Vestibularinjuries’, Proceedings of the Royal Societyof Medicine, 39, 273-278.

Cooksey, F S (1945). ‘Rehabilitation ofvestibular injuries’, Proceedings of theRoyal Society of Medicine, 39, 273-278.

Humphriss, R L, Baguley, D M,Peerman, S, Mitchell, T E and Moffat, D A (2001). ‘Clinical outcomesof vestibular rehabilitation’,Physiotherapy, 87, 7, 368-373.

Gillian Adams, managing editor ofthe journal, writes: ‘We apologisefor this error which should havebeen eliminated during sub-editing.’

I WOULD like to congratulatePhysiotherapy on its letters pages. Inparticular I found the recent series ofletters on evidence-based practice tobe informative and stimulating. Theeditorial comments placed after someof the letters were unobtrusive andprovided balance to what could havebecome a very heated interchange.

Physiotherapists lack a forum for expressing their thoughts abouttrends and priorities in the profession.Your letters pages go some way towards correcting this. Lately I havebeen reading the Members’ Forumdiscussions on the Physiotherapy PainAssociation website (ppaonline.co.uk)and have found it to be excellent.

Does the Chartered Society ofPhysiotherapy have such an online

forum? I think it would be an excellentmeans for therapists to exchangeopinions, ideas and information on anational platform.

Richard Shortall PTAlbuquerque, USA

Michael Jefford, CSP web editor,replies: ‘Currently there is no suchforum on the CSP website(http://www.csp.org.uk). The CSP didexperiment with several memberforums when the current websitewas launched back in 1999. All wereremoved due to lack of response.It may be appropriate to try againwith the current site rebuild,scheduled for release early in 2002.’

Any Opinions?