Table 17Calculated effect size: claudication onset measures

StudyType of Study
N Analyzeda
Quality
Outcome
Length of Followup
Results Reported by AuthorsCalculated Effect Sizeb
Medical therapy vs. usual care
Beebe, 199949RCT
N: 316
Good
PFWD (m)

6 mo
Mean geometric % change PFWD
Cilostazol 100: 1.51
Cilostazol 50: 1.38
Placebo: 1.15
Unable to compute (no exact p-value, SD in wrong units)
Dawson, 199886RCT
N: 66
Good
ICD (m)

12 wk
ICD (SE)
Cilostazol: baseline 71.2 (6.0)
3 mo 112.5 (13.8)
Placebo: 77.7 (8.4)
3 mo 84.6 (13.7)
ES (cilostazol): 0.68
EffSE: 0.25
Dawson, 200025RCT
N: 643
Fair
PFWD (m)

6 mo
Mean % change in PFWD
Pentoxifylline: 74 (106)
Cilostazol: 94 (127)
Placebo: 57 (93)
ES (pentoxifylline): 0.17
EffSE: 0.10

ES (cilostazol): 0.38

EffSE: 0.10
Hobbs, 200773

INEXACT Study
RCT
N: 18
Good
ICD (m)

6 mo
Ratio of 6 mo: baseline ICD (SD)
Cilostazol: 3.34 (4.23)
Best medical therapy: 1.23 (0.73)
ES (cilostazol): 0.72
EffSE: 0.49
Money, 199889RCT
N: 212
Fair
ICD (m)

4 mo
% change in ICD compared to placebo
Cilostazol: 27%
Unable to compute (no exact p-value or SD)
Exercise training vs. usual care
Treat-Jacobson, 200996RCT
N: 31
Good
PFWD (m)

24 wk
Change in PFWD (SD)
Walking: 155.1 (180.7)
Usual care: 10.9 (27.4)
Arm ergometry: 39.7 (97.2)
Walking + arm ergometry: 21.6 (81.3)
ES: 1.30
EffSE: 0.51
Crowther, 200866RCT
N: 21
Fair
PFWT (sec)

12 mo
Mean PFWT in seconds (SD): Exercise: baseline 132.8 (61.1)
1 yr 360.0 (188.3)
Control: 115.9 (99.5)
1 yr 166.3 (89.4)
ES: 1.06

EffSE: 0.47
Gardner, 200268RCT
N: 31
Fair
ICD (m)

18 mo
Percent Change in ICD
Exercise: 189%
Control: 0%
ES: 1.32

EffSE: 0.24
Gardner, 201169RCT
N: 63
Good
COT (sec)

12 wk
COT change from baseline (SD)
Supervised exercise: 165 (173)
Control: -16 (125)
Home exercise: 134 (197)
ES: 1.06

EffSE: 0.47
Gibellini, 200071RCT
N: 37
Fair
ICD (m)

6 mo
Mean ICD (SD)
Exercise: baseline 116.8 (48.2)
6 mo 351.4 (209.5)
Control: 111.6 (64.6)
6 mo 114.5 (79.6)
ES: 2.14
EffSE: 0.79
Hobbs, 200674

EXACT Study
RCT
N: 14
Fair
ICD (m)

6 mo
Median ICD (IQR)
Exercise: baseline 59 (35 to 63)
6 mo 92 (47 to169)
Best medical therapy: baseline 47 (30 to 118)
6 mo 56 (45 to 325)

Median ICD (range)
Usual care: baseline 59 (48 to 72)
6 mo 64 (47 to 77)
Usual care + exercise: baseline 60 (45 to 95)
6 mo 127 (62 to 180)
ES: 0.01
EffSE: 0.54
Hobbs, 200773

INEXACT Study
RCT
N: 18
Good
ICD (m)

6 mo
Overall effect at 6 mo (ICD)
Exercise: 1.80
Best medical therapy: 1.0
ES: 0.34
EffSE: 0.48
Lee, 200775Observational
N: 70
Poor
ICD (m)

6 mo
Median ICD (range)
Exercise: baseline 58.5 (39.2 to 112.7)
6 mo 107.5 (52.5 to 153.8)
Usual care: baseline 78.4 (39.2 to 131.2)
6 mo 75 (45 to 180)
Unable to compute (no SD or p-value)
Murphy, 201277

CLEVER Study
RCT
N: 58
Good
COT (sec)

6 mo
Mean change in COT from baseline (SD)
Exercise: 3.0 (2.9)
Usual care: 0.7 (1.1)
ES: 0.70

EffSE: 0.28
Tsai, 200279RCT
N: 53
Poor
COT (min)

3 mo
Mean COT (SD)
Exercise: baseline 3.3 (3.1)
3 mo 6.2 (2.7),
Usual care: baseline 2.9 (2.6)
3 mo 3.2 (3.4)
ES: 0.74

EffSE: 0.28
Endovascular intervention vs. usual care
Hobbs, 200674

EXACT Study
RCT
N: 16
Fair
ICD (m)

6 mo
Median ICD (IQR)
Baseline: Endovascular 84 (43 to 127), best medical therapy 47 (30 to 118)
6 mo: Endovascular 698 (147 to 1000), best medical therapy 56 (43 to 325)
ES: 0.74
EffSE: 0.52
Koivunen, 200892Observational
N: 129
Poor
PFWD (m)

12 mo
Median PFWD (IQR)
Baseline: Endovascular 100 (50 to 200), surgery 100 (50 to 200), usual care 200 (100 to 500)
12 mo: Endovascular 400 (100 to 10,000), surgery 2250 (2250 to 10,000), usual care 200 (100 to 1000)
Distribution of values are unusual therefore effect sizes cannot be computed
Murphy, 201277

CLEVER Study
RCT
N: 61
Good
COT (sec)

6 mo
Mean change in COT (SD)
Endovascular 3.6 (4.2)
Usual Care 0.7 (1.1)
ES: 0.88

EffSE: 0.28
Nylaende, 200793

OBACT Study
RCT
N: 56
Good
PFWD (m)

24 mo
Mean PFWD (SD)
Baseline: Endovascular 93.5 (72.9) usual care 69.6 (54.2), 24 mo: Endovascular 435.0 (223.8), usual care: 174.9 (171.8)
ES: 1.28
EffSE: 0.27
Whyman, 199795RCT
N: 19
Fair
ICD (m)

24 mo
Median ICD (IQR)
Baseline: Endovascular 56 (33 to 133), usual care 78 (58 to 100)
24 mo: Endovascular 383 (85 to 667), usual care 333 (106 to 667)
ES: 0.25
EffSE: 0.18
Endovascular intervention vs. exercise training
Greenhalgh, 200880
MIMIC Study
RCT
N: 94
Fair
ICD (m)

24 mo
Adjusted HR (95% CI)
Femoropopliteal group
Endovascular: 3.11 (1.42 to 6.81)
Exercise + optimal medical therapy 1.0

Aortoiliac group
Endovascular: 3.6 (1.0 to 12.8)
Exercise + optimal medical therapy 1.0
ES (femor): 0.61
EffSE: 0.21

ES (aorto): 0.70

EffSE: 0.36
Hobbs, 200674

EXACT Study
RCT
N: 16
Fair
ICD (m)

6 mo
Median ICD (IQR)
Baseline: Endovascular 84 (43 to 127), exercise 59 (35 to 63)
6 month: Endovascular 698 (147 to 1000), exercise 92 (47 to 169)
ES: 0.73
EffSE: 0.52
Mazari, 201282RCT
N: 109
Good
ICD (m)

12 mo
Median ICD (IQR)
Baseline: Endovascular 31.30 (20.70 to 63.13), exercise 42.71 (26.65 to 74.17)
12 mo: Endovascular 75.80 (46.07 to 209.82), exercise 103.15 (64.1 to 129.3)
ES (endo): 0.58
EffSE: 0.17

ES (ex): 0.61

EffSE: 0.06

ES (endo+ex): 0.49

EffSE: 0.16
Murphy, 201277

CLEVER Study
RCT
N: 79
Good
COT (sec)

6 mo
Mean change in COT from baseline in seconds (SD)
Endovascular 3.6 (4.2)
Exercise 3.0 (2.9)
Usual Care 0.7 (1.1)
ES: 0.18

EffSE: 0.23
Spronk, 200916RCT
N: 150
Fair
PFWD (m)

12 mo
Mean improvement in PFWD (99% CI)
Endovascular 806 (646 to 960)
Exercise 943 (786 to 1099)
ES (endo): 1.28
EffSE: 0.12

ES (ex): 1.52

EffSE: 0.11
Surgical revascularization vs. exercise training plus medical therapy (pentoxifylline)
Drozdz, 200167Prospective Cohort
N: 127
Fair
COT (min)

12 wk
Mean COT (SD)
Baseline: Usual care 2.8 (0.3), surgical revascularization 1.4 (0.5)
12 wk: Usual care 7.30 (0.9), surgical revascularization >10
Unable to compute (no exact p-value, categorical value for 12-wk surgical result)
Endovascular intervention vs. surgical revascularization
No studies
a

Number of patients in the study arms of interest.

b

Values used in meta-analysis appear in bold.

Abbreviations: COT=claudication onset time; EffSE=standard error of effect; ES=effect size; ICD=initial claudication distance; IQR=interquartile range; m=meters; min=minute/minutes; mo=month/months; PFWD=pain-free walking distance; PFWT=pain-free walking time; RCT=randomized controlled trial; SD=standard deviation; wk=week/weeks.

Number of patients in the study arms of interest.

Values used in meta-analysis appear in bold.

From: Results

Cover of Treatment Strategies for Patients With Peripheral Artery Disease
Treatment Strategies for Patients With Peripheral Artery Disease [Internet].
Comparative Effectiveness Reviews, No. 118.
Jones WS, Schmit KM, Vemulapalli S, et al.

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