Guarino 2006.

Study characteristics
Methods	Parallel RCT, cluster randomised
Data	USA, secondary care setting. All host trial participants included. Total n = 1092; mean age 40.6 (SD 8.7) years; 14.8% females; 53.8% white non‐Hispanic; 24.3% were Black, non‐Hispanic; Mean education years 14.0 (SD 1.9) years; 81% were employed.
Comparisons	Intervention group received a consent form that was revised by a consumer focus group. The changes involved revising treatment and eligibility descriptions, specifying participants would receive renumeration for three follow‐up visits but not treatment session, eliminating the enumeration for the risks of exercise. Control group received the original consent form with no modifications
Outcomes	Attendance at follow‐up visit/ collection of primary outcomes.
Notes	Retention period: 3‐, 6‐ and 12‐months.
Risk of bias
Item	Authors' judgement	Support for judgement
Allocation concealment?	Unclear	Not reported in the paper.
Adequate sequence generation?	Yes	Participating centres were randomised to either the participant‐ or investigator developed consent document in a 1:1 ratio.
Blinding of participants and personnel?	Yes	IRB and sites were only shown the consent form they were randomised to.
Blinding of outcome assessment?	Yes	Not reported in the paper. However, objective outcome, staff have no plausible additional opportunity to influence postal response rate once questionnaires sent.
Incomplete outcome data addressed? All outcomes	Unclear	It states missing data were excluded and not imputed, but it does not expand on this or highlight where there were missing data.
Free of selective outcome reporting?	Unclear	There is a lack of clarity around the definitions of 'retention' Adherence. At times this refers to visit attendance at other times primary outcome data
Other sources of bias	Unclear	No further concerns raised.
Overall Risk of Bias	Unclear	Unclear