TABLE 2

Selected Methodological Quality of Included Studies: Results Are Presented as Number of Studies (%)

True RandomizationAllocation ConcealmentBlinding of Outcome MeasurementBaseline ComparabilityRetention Rate ≥70% at 6 mo or ≥60% at 1 yIntention-to-Treat Analysis
Lifestyle interventions compared with no-treatment/wait-list control, n = 22 studiesYes7 (32)5 (23)3 (14)18 (82)16 (73)3 (14)
No0 (0)0 (0)2 (9)1 (4)1 (4)13 (59)
Unclear15 (68)17 (77)17 (77)3 (14)5 (23)6 (27)
Lifestyle interventions compared with standard care/minimal advice, n = 11 studiesYes5 (45)3 (27)2 (18)10 (91)8 (73)4 (36)
No0 (0)1 (0)1 (9)1 (9)2 (18)5 (46)
Unclear6 (55)7 (73)8 (73)0 (0)1 (9)2 (18)
Lifestyle interventions compared with written education materials, n = 5 studiesYes2 (40)1 (20)0 (0)4 (80)4 (80)2 (40)
No0 (0)0 (0)0 (0)1 (20)0 (0)2 (40)
Unclear3 (60)4 (80)5 (100)0 (0)1 (20)1 (20)