Ayala 2015.

Study characteristics
Methods	Puentes hacia una mejor vida (Bridges to a Better Life): Outcome of a diabetes control peer support intervention RCT (NA clusters and NA providers), conducted in 1) The Puentes study was conducted in the 3 largest Clinicas de Salud del Pueblo, Inc. (CDSDP) clinics, which are located in Brawley, El Centro, and Calexico, California, USA. And at a federally qualified health centre. 2) Intervention provided by peer leaders. In United States of America. 2 arms: 1) Control (usual care) (control arm) and 2) Intervention (peer support/leaders) (intervention arm)
Participants	Control arm N: 168 Intervention arm N: 168, NA, NA Diabetes type: 2 Mean age: 56.3 ± 11.4 % Male: 37 Longest follow‐up: 12 months
Interventions	Control arm: (usual care) Intervention arm: (peer support/leaders) 1) Case management
Outcomes	1) Retinopathy screening (dilated eye exam) 2) Foot screening 3) Glycated haemoglobin 4) Systolic blood pressure 5) Diastolic blood pressure
Funding source	Funding for this research was provided by the American Academy of Family Physicians Foundation through the Peers for Progress programme with support from the Eli Lilly and Company Foundation. Puentes hacia una mejor vida (Bridges to a Better Life; “Puentes”) was 1 of 8 international studies funded by Peers for Progress. Puentes was a partnership between a university‐affiliated research institute (Institute for Behavioral and Community Health; IBACH) and Clinicas de Salud del Pueblo, Inc. (CDSDP), an Federally Qualified Health Center (FQHC).
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported. Patients were then randomised to intervention or usual care. Randomisation was conducted by the study biostatistician and stratified by clinic.
Allocation concealment (selection bias)	Unclear risk	Not reported. Patients were then randomised to intervention or usual care. Randomisation was conducted by the study biostatistician and stratified by clinic.
Patient's baseline characteristics (selection bias)	Low risk	Participant characteristics are shown in Table 1. There was some indication that a greater percentage of intervention participants than usual care participants reported having a personal doctor (P = 0.09), while a greater percentage of usual care participants reported living below poverty thresholds (P = 0.08); no other group differences were observed.
Patient's baseline outcomes (selection bias)	Low risk	Table 4, P value above 0.05 for HbA1c, SBP and DBP at baseline.
Incomplete outcome data (attrition bias)	High risk	336 patients randomised, 32 excluded, leading to 304 patients and 60 lost to follow‐up (19.7%). Reasons for loss to follow‐up not reported.
Blinding of participants and personnel (performance bias) and of outcome assessors (detection bias)	Low risk	Our outcomes of interest are all objective (HbA1c, SBP, DBP). Health care use including ophthalmology and podiatry visits were abstracted from medical records.
Selective reporting (reporting bias)	Unclear risk	Retrospectively registered protocol (protocol first posted on July 2014, study start date: February 2009). They do not report the results for changes in cholesterol, HDL, LDL and triglycerides, depression and distress (all listed as secondary outcomes in protocol).
Risk of contamination (other bias)	Low risk	The peer leaders only meet with the intervention group.
Other bias	Low risk	No evidence of other bias.