SUPPLEMENTARY MATERIAL
Supplementary Table S1: Search terms used in each of the databases. Database “CDI” related search terms “Cost” related search terms
Medline®
Embase
exp Clostridium difficile/ OR exp Clostridium/ OR exp Clostridium Infections/ OR clostridium difficile.mp. OR difficile.mp. OR Cdifficile.mp. OR (C adj difficile).mp. OR difficile clostridium.mp. OR Cdiff.mp. OR (C adj diff).mp.
exp Economics/ OR Economics.mp. OR exp "costs and cost analysis"/ OR (cost$ adj analysis).mp. OR exp Cost allocation/ OR cost allocation.mp. OR exp "Cost-benefit analysis"/ OR (cost-benefit adj analysis).mp. OR exp Cost control/ OR cost control.mp. OR exp Cost savings/ OR cost savings.mp. OR exp "Cost of illness"/ OR (cost adj2 illness).mp. OR exp Cost sharing/ OR cost sharing.mp. exp "deductibles and coinsurance"/ OR (deductibles adj coinsurance).mp. OR exp Medical savings accounts/ OR medical savings accounts.mp. OR exp Health care costs/ OR health care costs.mp. OR exp Direct service costs/ OR Direct service costs.mp. OR exp Drug costs/ OR drug costs.mp. OR exp Employer health costs/ OR Employer health costs.mp. OR exp Hospital costs/ OR hospital costs.mp. OR exp Health expenditures/ OR Health expenditures.mp. OR exp Capital expenditures/ OR Capital expenditures.mp. OR exp "Value of life"/ OR (value adj life).mp. OR exp economics, hospital/ OR exp economics, medical/ OR exp Economics, nursing/ OR exp OR Economics, pharmaceutical/ OR exp "fees and charges"/ OR exp budgets/ OR (low adj cost).mp. OR (high adj cost).mp. OR (health?care adj cost$).mp. OR (fiscal or funding or financial or finance).tw. OR (cost adj estimate$).mp. OR (unit adj cost$).mp. OR (economic$ or pharmacoeconomic$ or price$ or pricing).tw. OR (cost adj variable).mp. OR (cost-effect* or "cost effect*").mp. OR exp Quality-Adjusted Life Years/ OR quality-adjusted life years.mp. OR quality adjusted life years.mp. OR qaly.mp. OR (life adj years).mp. OR cost utili*.mp. OR (cost adj2 utili*).mp. OR (cost adj2 effect*).mp. OR exp models, economic/ OR (economic$ adj2 model$).mp. OR (cost adj2 utilit*).mp. OR (cost adj2 consequenc*).mp. OR net benefit.mp. OR (willingness adj2 pay).mp.
Health Technology Assessment Database
NHS Economic Evaluation Database
Cost-Effectiveness Analysis Registry
EconLit
Clostridium difficile None
CDI - C. difficile infection, NHS – National Health Service
1
Supplementary Table S2: Quality assessment tool and how it was applied the COI studies.
Questions from Drummond and Jefferson (1) The application of each question to a COI study
Section(s) in which the item should be found
Answer options
1. The research question is stated
Does the objective state that the economic impact of the disease is being determined? Examples of other terms that can be used include: cost, expenses, economic burden, financial impact
If the actual disease (e.g., CDI) is not mentioned in the objective but represented within a group of diseases (e.g., hospital acquired infections), then put “partially”
ObjectiveY NP
2. The economic importance of the research question is stated
If question 1 is "yes" or “partially” then is the rationale behind the cost analysis stated?
If question 1 is "no" then put “not applicable”
Introduction Objective
Y NNA
3. The viewpoint(s) of the analysis are clearly stated and justified
Does the study state the "perspective" or "viewpoint" of the cost analysis? Examples of perspectives include: hospital, government, patient, insurance company, society, caregiver
A justification behind the perspective chosen should also be stated
If the perspective is only stated and not justified, then put "partially"
IntroductionObjective
YNP
4. The form of economic evaluation used is stated
Are the epidemiological approach (e.g., incidence/prevalence-based approach (2, 3)) and method of resource quantification (e.g., top-down/bottom-up approach (2, 3)) stated?
If one or the other is stated then put “partially”
ObjectiveMethods
YNP
5. The primary outcome measure(s) for the economic evaluation are clearly stated
Does the study state which cost outcomes are being evaluated? For example, cost per patient, cost per episode, total cost
MethodsResults
YN
6. Details of the subjects from whom valuations were obtained are given
Does the study provide details on the sample population in which the costs are being obtained from? For example, demographics
Results Y N
7. Productivity changes (if included) are reported separately
Does the study evaluate indirect costs? ObjectiveMethods
YNNA
8. The relevance of productivity changes to the study question is discussed
If question 7 is "yes" then answer "yes" or "no"
If question 7 is "no" then put "not applicable"
IntroductionObjective Methods Discussion
YNNA
2
Questions from Drummond and Jefferson (1) The application of each question to a COI study
Section(s) in which the item should be found
Answer options
9. Quantities of resources are reported separately from their unit costs
Are resource utilization variables reported separately from their costs? For example, if hospitalization costs are reported, is length of stay provided? Or if physician costs are provided, are number of physician visits reported?
Results YN
10.Methods for the estimation of quantities and unit costs are described
Does the study describe how resource utilization and costs are estimated? For example, are they obtained from a survey, a database, or expert opinion?
If the methods of either the resource utilization variables or costs are only reported, then put "partially"
If the methods are discussed in the results or discussion sections then put “partially”
MethodsYNP
11.Currency and price data are recorded
Does the study state the year and currency in which the costs are evaluated in?
If only one or the other is stated then put "partially"
Methods Results
YNP
12.Time horizon of costs and benefits is stated
Does the study state the time horizon in which the costs are evaluated over? For example, costs over hospitalization/admission, year, lifetime
MethodsResults
YN
13.The discount rate(s) is stated
If future costs are calculated, are the costs discounted? Methods
YNNA
14.The choice of rate(s) is justified
If question 13 is "no" then put down "not applicable" Methods
YNNA
15.An explanation is given if costs or benefits are not discounted
If question 13 is "no" then put down "not applicable" Methods
YNNA
16.Details of statistical tests and confidence intervals are given for stochastic data
Are descriptive statistics presented for cost estimates (e.g., mean, median, standard deviation, max, min, range)?
Are confidence intervals or p-values given?
If either/or is stated, then put "partially"
ResultsYNP
17.The approach to sensitivity analysis is given
Is a sensitivity analysis conducted around costs?
If the description of sensitivity analysis is found in the results and discussion sections, put “partially”
MethodsYNP
18.The choice of variables for sensitivity analysis is justified
If question 17 is "no" then put "not applicable" MethodsYNNA
3
Questions from Drummond and Jefferson (1) The application of each question to a COI study
Section(s) in which the item should be found
Answer options
19.The ranges over which the variables are varied are stated
If question 17 is "no" then put "not applicable" MethodsYNNA
20.Incremental analysis is reported
Did the study mention the use of a comparison group?
If this is done for only part of the cohort then put “partially”
ResultsYNP
21.Major outcomes are presented in a disaggregated as well as aggregated form
Are the costs reported by subgroups, such as sex, age, region, resource? Results Y
N
22.Conclusions are accompanied by the appropriate caveats
Are the limitations around the cost analysis (e.g., cohort, cost methods) discussed?
Discussion Conclusions
YN
COI - Cost of illness; CDI - C. difficile infection; Y- Yes; N – No; P- Partially; NA- Not applicable.
4
Supplementary Table S3: Summary of CDI COI studies by country.Au
thor
and
yea
r of
pub
licati
on
Patie
nt
popu
latio
n
CDI d
efini
tion
base
d on
Sam
ple
size
of
thos
e w
ith C
DI
Sam
ple
size
of
com
paris
on
grou
p
Reso
urce
uti
lizati
on
varia
bles
in
clud
ed
Reso
urce
and
co
st so
urce
s
Tim
e fr
ame
of
data
ext
racti
on
Tim
e ho
rizon
for
cost
s
Cost
out
com
e(s)
Type
of m
etho
d to
cal
cula
te
cost
s
Cost
of t
hose
w
ith C
DI(U
S 20
14 $
)
Cost
of
com
paris
on
grou
p(U
S 20
14 $
)
Attrib
utab
le
cost
(US
2014
$)
p-va
lue
Australia
Jackson 2011 (4) Hospitalized ICD code 233 - HospitalizationComputerized clinical costing
systems
2 y(2005 to
2007)
LOS
Mean cost per episode RA - - $13,819 <0.05
Canada
Miller 2002 (5) CDI readmission LAB, SYM 10 -Hospitalization and antibiotic
therapy
Study results and expert opinion
6 w(Jan and
Apr 1997)
LOS
Mean cost per patient SUM $11,240 - - -
Butterworth 1998 (6) Hospitalized LAB 100 -
Laboratory and antibiotic therapy
St. Paul’s Hospital 1 y(1996) 1 y Cost per
patient SUM $714 - - -
Germany
Vonberg 2008 (7) Hospitalized LAB, SYM 45 -
Hospitalization, procedures,
drugs
Hannover Medical School finance
department
1 y(2006)
LOS
Median cost per patient HM - - $9,730 -
Ireland
Al-Eidan 2000 (8) Hospitalized LAB, SYM 87 -
Hospitalization, laboratory, drug
therapy
Antrim Area Hospital Corporate
Information Department
2 y LOS
Mean cost per case SUM - - $4,124 -
Japan
Yasunaga 2012 (9)
Hospitalized, underwent elective
digestive tract surgery for cancer
ICD code 409143,243
409 (PSM)
Surgery, pharmaceuticals
, laboratory, radiology,
nursing care, and other
Japanese Diagnosis Procedure
Combination database
2 y(Jul to
Dec for each year
from 2007 to 2010)
LOS Total costs
SUMRA
PSM
$33,547-
$33,547
$23,670-
$26,580
-$6,814$6,967
<0.001<0.001<0.001
United Kingdom
Wilcox 1996 (10)
Hospitalized, >65 years LAB, SYM 50 92 Bed, treatment,
laboratory
Study results, government
sources, and expert opinion
7 m(Dec
1994 to Jun 1995)
LOS
Mean cost per patient SUM - - $9,703 -
United States
Campbell 2013 (11)
Hospitalized: 1) > 65 years; 2) renal
disease; 3) cancer; 4) IBD; 5) concomitant
antibiotic use
LAB 4,521 - HospitalizationHealth Facts
electronic health record database
6 y and 2 m (Apr 2005 to
Jun 2011)
LOS
Mean hospital costs
(depending on the patient
group)
SUM
PSM
$40,186- $78,933
-
-
-
-
-$1,522-$18,563
-
<0.05 for
groups 1, 2,
and 5
Jiang 2013 (12) Hospitalized ICDcode 1,211 6,053 Hospitalization
Rhode Island Department of
Health’s Centre for Health Data and
Analysis
2 y(Jan 2010
to Dec 2011)
LOS
Mean costsMedian costs PSM $35,473
$20,998$17,474$9,714
$17,999$11,284
<0.0001-
5
Auth
or a
nd y
ear
of p
ublic
ation
Patie
nt
popu
latio
n
CDI d
efini
tion
base
d on
Sam
ple
size
of
thos
e w
ith C
DI
Sam
ple
size
of
com
paris
on
grou
p
Reso
urce
uti
lizati
on
varia
bles
in
clud
ed
Reso
urce
and
co
st so
urce
s
Tim
e fr
ame
of
data
ext
racti
on
Tim
e ho
rizon
for
cost
s
Cost
out
com
e(s)
Type
of m
etho
d to
cal
cula
te
cost
s
Cost
of t
hose
w
ith C
DI(U
S 20
14 $
)
Cost
of
com
paris
on
grou
p(U
S 20
14 $
)
Attrib
utab
le
cost
(US
2014
$)
p-va
lue
Pant 2013 (13) Hospitalized, children with IBD ICD code 447 12,163 Hospitalization
Healthcare Cost and Utilization Project
Kids’ Inpatient Database
1 year (2009)
LOS
Mean hospitalizatio
n chargesRA $46,084 $35,439 $10,644 <0.001
Quimbo 2013 (14)
Hospitalized: 1) immunocompromised
; 2) CDI history; 3) concomitant
antibiotic use; 4) renal impairment; 5)
IBD; 6) > 65 years
ICD code 933-10,933
933-32,799 Hospitalization
HealthCore Integrated Research
Database
5 y and 10 m (Jan 2005 to
Oct 2010)
LOS
Mean hospitalizatio
n costRA $42,027-
$201,174$22,196-78,878
$11,823-$122,295 <0.001
Sammons 2013 (15)
Hospitalized, children, community- and
hospital-onset of CDI
ICD code, LAB 4,474 8,821 Hospitalization
Pediatric Health Information System
database
5 y and 8 m (Jan
2006 to Aug
2011)
LOS
Mean total cost PSM, RA - - $19,207-
$95,118 -
Tabak 2013 (16) Hospitalized LAB 255 765 Hospitalization
Hospitals, clinical research database from CareFusion, and Centers for Medicare and
Medicaid Services
1.5 y(Jan 2007
to Jun 2008)
LOS
Mean cost per case
Median cost per case
PSM
$32,921
$21,245
26,674
$16,987
$6,247
$4,258
-
-
Wilson 2013 (17)
Hospitalized, underwent closure of
loop ileostomyICD code 217 13,245 Hospitalization Nationwide
Inpatient Sample
5 y(2004 to
2008)
LOS Mean costs SUM
RA$41,232
-$17,635
-$23,597$20,399
-<0.001
Ali 2012 (18)Hospitalized,
underwent liver transplants
ICD code 5,159 193,174 Hospitalization Nationwide Inpatient Sample
5 y(2004 to
2008)
LOS
Mean hospital charges SUM $148,173 $75,641 - <0.01
Kim 2012 (19)
Hospitalized, underwent radical
cystectomy for bladder cancer
ICD code - - Hospitalization Nationwide Inpatient Sample
8 y(2001 to
2008)
LOS
Hospitalization cost RA $57,368 $32,359 - <0.001
Kuntz 2012 (20)
Patients identified with CDI in an outpatient and
inpatient setting
ICD code, LAB, AT(OPTS)
ICD code (IPTS)
1,316- 1,650 -
Emergency department
visits, laboratory, pharmacy,
physician visits, hospitalization
Kaiser Permanente Northwest/Colorado
, Medicare and Medicaid
3 y and 3 m (Jun 2005 to
Sept 2008)
180 d
Costs per patient SUM $1,875-
$12,503 - - -
Lipp 2012 (21) Hospitalized ICD code - - Hospitalization
New York State Department of
Health’s Statewide Planning and
Research Cooperative System
2 y(2007 to
2008)
LOS
Mean cost per infection RA - - $30,049 -
McGlone 2012 (22)
Hypothetical sample, hospitalized, >65
years (recurrence of CDI included in
economic model)
- - -
Hospitalization, diagnostic
procedures, drugs, surgical
procedures, loss in productivity
Government and published sources - 1 y
Median cost per case
(depending on the
perspective and
recurrence rate)
- - - $9,745-$17,962 -
Pant 2012 (23) Hospitalized, ICD code - - Hospitalization Nationwide 1 y LO Median SUM $55,755 $32,627 - <0.001
6
Auth
or a
nd y
ear
of p
ublic
ation
Patie
nt
popu
latio
n
CDI d
efini
tion
base
d on
Sam
ple
size
of
thos
e w
ith C
DI
Sam
ple
size
of
com
paris
on
grou
p
Reso
urce
uti
lizati
on
varia
bles
in
clud
ed
Reso
urce
and
co
st so
urce
s
Tim
e fr
ame
of
data
ext
racti
on
Tim
e ho
rizon
for
cost
s
Cost
out
com
e(s)
Type
of m
etho
d to
cal
cula
te
cost
s
Cost
of t
hose
w
ith C
DI(U
S 20
14 $
)
Cost
of
com
paris
on
grou
p(U
S 20
14 $
)
Attrib
utab
le
cost
(US
2014
$)
p-va
lue
underwent solid organ transplants Inpatient Sample (2009) S
hospital charges
Mean hospital charges
RA - - $72,167 <0.001
Pant 2012 (24)Hospitalized with end-stage renal
diseaseICD code - - Hospitalization Nationwide
Inpatient Sample1 y
(2009)LOS Mean charges SUM
RA$129,363
-$58,713
--
$65,097<0.001<0.001
Peery 2012 (25) Hospitalized ICD code 110,553 discharges - Hospitalization Nationwide
Inpatient Sample1 y
(2009)LOS Median costs SUM $7,019 - - -
Verlee 2012 (26) Hospitalized ICD code 49,516 - Hospitalization Michigan Health and
Hospital Association
7 y(Jan 2002
to Dec 2008)
LOS
Mean charges (depending on if principal or non-principal
diagnosis)
SUM $27,458-$90,185 - - -
Arora 2011 (27) Hospitalized LAB, SYM 85 -
Daily ward, ICU, diagnostic tests, physician visits,
other health professionals,
pharmacy
St Luke’s Episcopal Hospital accounting
database
1 y and 2 m (Mar 2007 to
May 2008)
3 m
Median hospital costs(depending on Horn’s index
score)
SUM $9,080- $72,667 - - -
Glance 2011 (28)
Hospitalized with trauma ICD code 768 148,888 Hospitalization Nationwide
Inpatient Sample
2 y(2005 to
2006)
LOS Median cost SUM $35,212 $13,589 - -
Lesperance 2011 (29)
Hospitalized with elective colon
resectionsICD code 10,077 695,010 Hospitalization Nationwide
Inpatient Sample
3 y(2004 to
2006)
LOS
Hospital charges SUM $141,939 $65,863 - <0.05
Nylund 2011 (30) Hospitalized, children ICD code 21,274 10,474,45
4 Hospitalization
Healthcare Cost and Utilization Project
Kids’ Inpatient Database
4 y(1997, 2000,
2003, and 2006)
LOS
Median hospitalization charges per
patient (depending on
the year)
SUM $25,544- $35,437
$9,611- $12,079 -
<0.001 for
1997, 2000, and
2006
Pakyz 2011 (31) Hospitalized ICD code, AT 10,857 19,214
Hospital care, laboratory, and
drugs
University Health System Consortium
Clinical Resource Manager program
6 y(Apr 2002
to Mar 2007)
LOS
Mean hospitalizatio
n cost
Median hospitalizatio
n cost
Mean cost per patient
SUM
RA
$64,720
$39,590
$63,988
$33,546
$15,139
$32,825
-
-
<0.001
-
Stewart 2011 (32) Hospitalized ICD code 41,207 41,207-
4,032,865 Hospitalization Nationwide Inpatient Sample
1 y(2007)
LOS
Mean hospitalizatio
n cost
SUMPSM
$24,689$24,689
$9,781$15,778
-$8,911
-<0.000
1
Wang 2011 (33) Hospitalized ICD code 78,273 - Hospitalization
Pennsylvania Health Care Cost
Containment Council
4 y(2005 to
2008)
LOS
Mean hospital cost per
admission
Median hospital cost
per admission
PSM
$24,413
$12,078
$12,005
$7,166
$12,408
$4,913
<0.0001
Bajaj 2010 (34) Hospitalized with ICD code - - Hospitalization Nationwide 1 y LO Total RA $86,572 $38,934 - <0.001
7
Auth
or a
nd y
ear
of p
ublic
ation
Patie
nt
popu
latio
n
CDI d
efini
tion
base
d on
Sam
ple
size
of
thos
e w
ith C
DI
Sam
ple
size
of
com
paris
on
grou
p
Reso
urce
uti
lizati
on
varia
bles
in
clud
ed
Reso
urce
and
co
st so
urce
s
Tim
e fr
ame
of
data
ext
racti
on
Tim
e ho
rizon
for
cost
s
Cost
out
com
e(s)
Type
of m
etho
d to
cal
cula
te
cost
s
Cost
of t
hose
w
ith C
DI(U
S 20
14 $
)
Cost
of
com
paris
on
grou
p(U
S 20
14 $
)
Attrib
utab
le
cost
(US
2014
$)
p-va
lue
cirrhosis Inpatient Sample (2005) S hospitalization charges
Fuller 2009 (35) Hospitalized ICD code
1,282 (Maryland
)
2,478 (California
)
- Hospitalization
Maryland: Health Services and Cost
Review Commission
California: Office of Statewide Planning and Development
Maryland: 1 y
(Jul 2007 to Jun 2008)
California:
1 y(Oct 2005
to Sept 2006)
LOS
Mean patient cost RA - -
Maryland: $18,529
California:
$28,167
-
Reed 2009 (36)Hospitalized, DRG
127, 148, 182, 415, and 416
- 524 7,107 - Hospital’s private administrative data
5 y(2002 to
2006)
LOS
Charges(depending on
the DRG)SUM $8,527-
$44,217$5,080- $26,347 - <0.001
Zilberberg 2009 (37)
Hospitalized with prolonged acute
mechanical ventilation
ICD code 3,370 3,363-61,442 Hospitalization Nationwide
Inpatient Sample1 y
(2005)LOS
Mean hospital costs
Total cost
SUM
PSM
$82,860
-
$63,219
-
-
$11,483
<0.001
-
Ananthakrishnan 2008 (38) Hospitalized with IBD ICD code 2,804 77,366 Hospitalization Nationwide
Inpatient Sample1 y
(2003)LOS
Median hospital charges
Mean hospital charges
SUM
RA
$21,600
-
$14,885 -
$12,604
-
-
Dubberke 2008 (39)
Hospitalized, nonsurgical LAB 342-439 342-
24,252
Room and board,
pharmacy, laboratory, radiology,
respiratory therapy,
physical therapy
Barnes-Jewish Hospital’s Medical
Informatics and Trendstar financial
databases
1 y(2003)
LOS
and
180 d
Median total costs
Mean costs (depending on
the time horizon)
Median costs (depending on
the time horizon)
SUM
RA
PSM
$17,575
$9,275- $16,088
$16,099- $30,259
$7,537
$6,563- $10,517
$10,777- $16,541
-
$2,712- $5,571
$3,580- $7,932
<0.001
-
-
Nguyen 2008 (40)
Hospitalized with IBD (Crohn’s disease and
Ulcerative colitis)ICD code - - Hospitalization Nationwide
Inpatient Sample
7 y(1998 to
2004)
LOS
Mean hospital charges SUM
Ulcerative colitis: $40,854
Crohn’s disease: $39,038
Ulcerative colitis: $27,372
Crohn’s disease: $23,379
- <0.0001
Song 2008 (41) Hospitalized LAB 630 630 -
John Hopkins Hospital
administrative finance system
4 y and 10 m
(Jan 2000 to Oct 2005)
LOS Median costs PSM $22,824 $26,024 -$3,200 -
Lawrence 2007 Hospitalized, ICU LAB 75 1,760 Hospitalization Barnes-Jewish 2.5 y LO Median cost SUM $60,711 $24,623 - <0.001
8
Auth
or a
nd y
ear
of p
ublic
ation
Patie
nt
popu
latio
n
CDI d
efini
tion
base
d on
Sam
ple
size
of
thos
e w
ith C
DI
Sam
ple
size
of
com
paris
on
grou
p
Reso
urce
uti
lizati
on
varia
bles
in
clud
ed
Reso
urce
and
co
st so
urce
s
Tim
e fr
ame
of
data
ext
racti
on
Tim
e ho
rizon
for
cost
s
Cost
out
com
e(s)
Type
of m
etho
d to
cal
cula
te
cost
s
Cost
of t
hose
w
ith C
DI(U
S 20
14 $
)
Cost
of
com
paris
on
grou
p(U
S 20
14 $
)
Attrib
utab
le
cost
(US
2014
$)
p-va
lue
(42) Hospital financial accounting system
(Jul 1997 to Dec 1999)
S per patient
O'Brien 2007 (43) Hospitalized ICD code
Principal diagnosis:
1,036
Non-principal
diagnosis: 2,656
-
Hospitalization, pharmacy, laboratory,
imaging, emergency department
Massachusetts hospital discharge
databases
1 y(2000)
LOS
Mean cost per stay
Median cost per stay
Principal diagnosis:
SUM, non-
principal diagnosis:
HM
$11,717- $34,377
$6,840- $15,876
-
Non-principal
diagnosis:$15,690
$6,244
-
Zerey 2007 (44) Hospitalized, surgical ICD code 8,113 1,553,597 Hospitalization Nationwide Inpatient Sample
5 y(1999 to
2003)
LOS
Median total charges
Total charges
SUM
RA
$72,496
-
$19,772
-
-
$88,902
<0.0001
<0.0001
Kyne 2002 (45) Hospitalized LAB. SYM - - Hospitalization
Beth Israel Deaconess Medical
Centre Hospital billing system
5 m(Jan 1998
to May 1998
LOS
Median hospital cost
Hospital cost
SUM
RA
$16,263 $7,616 -
$4,852
<0.0001
0.003
McFarland 1999 (46) Recurrent CDI LAB, SYM 209 -
Clinic visits, antibiotics,
laboratory tests, enteric
pathogen and fecal leukocyte examinations, room charge,
physician visit, and procedures
Medical billing records and
laboratory charges
3y and 5m
(Aug 1993 to
Dec 1996)
LT Mean per person SUM $15,665 - - -
Kofsky 1991 (47) Hospitalized LAB 155 -
Bed, laboratory tests, medical
treatmentHospital 1 y
(1988)LOS
Mean charges per patient SUM $3,764 - - -
Yannelli 1988 (48)
Hospitalized, suspected CDI SYM
126 (positive
and negative)
- Laboratory testing -
1.5 y(Jan 1986
to Jun 1987)
1.5 y
Total cost to the hospital SUM $4,591 - - -
CDI – C. difficile infection; COI – Cost-of-illness; US – United States; ICD – International Classification of Diseases; y – Year(s); LOS – Length of stay; RA – Regression analysis; LAB – Laboratory tests (related to CDI); SYM – Symptoms (related to CDI); w – Week(s); SUM – Summation; HM – Hard matching; PSM – Propensity score matching; m – Month(s); IBD – Inflammatory bowel disease; AT – Antibiotic therapy (vancomycin and/or metronidazole); OPTS – Outpatient setting; IPTS – Inpatient setting; d – Day(s); DRG – Diagnosis Related Groups; ICU – intensive care unit; LT – Lifetime.
9
Supplementary Table S4: Quality assessment results.Country Author and year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
Australia Jackson 2011 (4) [+] + + - + - NA NA - [+] [+] + NA NA NA + - NA NA + - +
CanadaMiller 2002 (5) - NA - - - - NA NA + [+
] [+] + NA NA NA [+] - NA NA - - -
Butterworth 1998 (6) + - - - + - NA NA + [+] - + NA NA NA - - NA NA - + -
Germany Vonberg 2008 (7) + + - - + + NA NA + + - + NA NA NA + - NA NA + + +Ireland Al-Eidan 2000 (8) + - - - + + NA NA + + [+] + NA NA NA [+] - NA NA + + -Japan Yasunaga 2012 (9) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + + +
United Kingdom Wilcox 1996 (10) + + - - + + NA NA + [+] [+] + NA NA NA [+] - NA NA + + +
United States Campbell 2013 (11) + + - - + + NA NA + + [+] + NA NA NA + + - + + - +Jiang 2013 (12) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + - +Pant 2013 (13) - NA - - + + NA NA + + - + NA NA NA + - NA NA + + -Quimbo 2013 (14) + + - - + + NA NA + + + + NA NA NA + - NA NA + + +Sammons 2013 (15) - NA - - + + NA NA + + - + NA NA NA + - NA NA + + +Tabak 2013 (16) + + - - + + NA NA + + - + NA NA NA + + - + + - +Wilson 2013 (17) + - - - + + NA NA + + + + NA NA NA + - NA NA + - +Ali 2012 (18) - NA - - + + NA NA + + - + NA NA NA + - NA NA + + +Kim 2012 (19) [+] + - - + - NA NA + + + + NA NA NA + - NA NA + - +Kuntz 2012 (20) + + - - + + NA NA + + + + NA NA NA - - NA NA - + +Lipp 2012 (21) + + + - + - NA NA + + - + NA NA NA [+] - NA NA + - +McGlone 2012 (22) + + + - + + + + + + + + + - NA + + + + + + +Pant 2012 (23) - NA - - + + NA NA + + - + NA NA NA + - NA NA + - +Pant 2012 (24) - NA - - + + NA NA + + - + NA NA NA + - NA NA + - -Peery 2012 (25) - NA - - + - NA NA + + [+] + NA NA NA [+] - NA NA - - +Verlee 2012 (26) + + - - + + NA NA + + + + NA NA NA [+] - NA NA - + +
Arora 2011 (27) + + - - + + NA NA - [+] - + NA NA NA [+] - NA NA - - +
Glance 2011 (28) + + - - + + NA NA + + - + NA NA NA [+] - NA NA + + +Lesperance 2011 (29) - NA - - + + NA NA + + - + NA NA NA [+] - NA NA + - +Nylund 2011 (30) - NA - - + + NA NA + + [+] + NA NA NA + - NA NA + - +
Pakyz 2011 (31) + + + - + + NA NA + + + + NA NA NA + [+] - + + + +
Stewart 2011 (32) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + - +Wang 2011 (33) + + - - + + NA NA - + [+] + NA NA NA + [+
]- + + + +
10
Country Author and year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22Bajaj 2010 (34) + - - - + + NA NA + + - + NA NA NA + - NA NA + - +Fuller 2009 (35) [+] + + - + - NA NA - + - + NA NA NA [+] - NA NA + - +Reed 2009 (36) + - [+] - + - NA NA + - - + NA NA NA + - NA NA + + -Zilberberg 2009 (37) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + - +Ananthakrishnan 2008 (38) - NA - - + + NA NA + + - + NA NA NA + - NA NA + - +
Dubberke 2008 (39) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + + +Nguyen 2008 (40) - NA - - + - NA NA + + + + NA NA NA + - NA NA + - +Song 2008 (41) + + + - + + NA NA + + - + NA NA NA [+] - NA NA + + +Lawrence 2007 (42) - NA - - + + NA NA + + + + NA NA NA + - NA NA + + +O'Brien 2007 (43) + - - - + + NA NA + + + + NA NA NA [+] - NA NA [+] - +Zerey 2007 (44) + + - - + + NA NA + + - + NA NA NA + - NA NA + + +Kyne 2002 (45) + + - - + + NA NA + + [+] + NA NA NA + - NA NA + - +McFarland 1999 (46) - NA - - + + NA NA - + - + NA NA NA [+] - NA NA - - +Kofsky 1991 (47) + + + - + + NA NA + + - + NA NA NA [+] - NA NA - + -Yannelli 1988 (48) - NA - - - - NA NA + - - + NA NA NA - - NA NA - + -
1 The research question is stated; 2 The economic importance of the research question is stated; 3 The viewpoint(s) of the analysis are clearly stated and justified; 4 The form of economic evaluation used is stated; 5 The primary outcome measure(s) for the economic evaluation are clearly stated; 6 Details of the subjects from whom valuations were obtained are given; 7 Productivity changes (if included) are reported separately; 8 The relevance of productivity changes to the study question is discussed; 9 Quantities of resources are reported separately from their unit costs; 10 Methods for the estimation of quantities and unit costs are described; 11 Currency and price data are recorded; 12 Time horizon of costs and benefits is stated; 13 The discount rate(s) is stated; 14 The choice of rate(s) is justified; 15 An explanation is given if costs or benefits are not discounted; 16 Details of statistical tests and confidence intervals are given for stochastic data; 17 The approach to sensitivity analysis is given; 18 The choice of variables for sensitivity analysis is justified; 19 The ranges over which the variables are varied are stated; 20 Incremental analysis is reported; 21 Major outcomes are presented in a disaggregated as well as aggregated form; 22 Conclusions are accompanied by the appropriate caveats; “+” refers to “yes”; “[+]” refers to “partially”; “-“ refers to “no”; “NA” refers to “not applicable”; Questions 1 to 22 are from Drummond and Jefferson (1); See Supplementary Table 2 for our interpretation of each question; Table format is based on Davis et al (49).
11
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