. 2016 Nov;14(6):540–551. doi: 10.1370/afm.1982

Table 1.

Descriptive Summary of the Characteristics of Included Studies

Study, Year	Patients, No.	Setting, Population	Intervention	Control	Duration of Peer Training	Peer Supervision	Attendance Rates, Intensity
Keyserling et al,²³ 2002	133	United States: African American women Mean HbA_1c 11.1%	Same as control; also 3 group sessions and monthly telephone calls from a peer counselor for 12 mo 7 peer counselors for 67 patients	Individual counseling visits with nutritionist at mo 1, 2, 3, and 4	16 h	None reported	81% of participants attended at least 1 peer counselor session, 30% attended 2 sessions, and 19% attended 3 sessions Average phone calls per participant: 9.7
Lorig et al,²⁶ 2008	417	United States: Spanish-speaking patients Mean HbA_1c 7.41%	6-wk program: 2.5 h weekly led by 2 peer leaders 2 peers per 10–15 patients	Usual care	24 h	Random observations	Not reported
Lorig et al,²⁵ 2009	345	United States: white, non-Hispanic patients 67% Mean HbA_1C 6.72%	6-wk program: 2.5 h weekly led by 2 peer leaders 2 peers per 10–15 patients	Usual care	24 h	Random observations	Mean attendance of 4.9 of 6 sessions
Dale et al,³² 2009	187	United Kingdom: white, non-Hispanic patients 96.65% Mean HbA_1c 8.55%	Peer supporter called participants after change in their diabetes care at days 7–10, 14–18, 28–35, 56–70, 120–150 1 peer called median of 10 patients	Usual care	2-d training program developed for the study	None reported	Mean number of calls each patient received: 4.5 (range = 1–6 calls; SD, 2.2)
Cade et al,³¹ 2009	207	United Kingdom: white, European-origin patients 95% Mean HbA_1C 7.4%	Peer educators delivered 2-h education sessions per week for 7 wk 5 peer educators for 86 participants	Usual care	Residential training course provided by the Expert Patients Programme of the National Health Service	None reported	Of 110 participants in intervention group, 18 attended only 1 session and 22 attended all 7 sessions 63 participants attended final diabetes-specific session
Heisler et al,²² 2010	244	United States: Male veterans, white non-Hispanic 82% Mean HbA_1c 7.97%	Peer partners encouraged to call weekly Three optional 1.5-h face-to-face sessions at 1, 3, and 6 mo	Usual care	Initial 1.5-h training in peer communication skills	Interactive voice response–facilitated telephone platform recorded call initiation, frequency, and duration	90% of peer pairs had at least 1 conversation; average number of calls per pair per month was 2.4, 1.7, 1.4, 1.0, 0.9, 0.8 for 6 consecutive mo
Philis-Tsimikas et al,²⁷ t2011	207	United States: Mexican Americans Mean HbA_1c 10.4%	Weekly 2.5-h education sessions by peer educators for 8 wk	Usual care	40 h of training, plus trainees cotaught 2 series of classes with their trainer and taught 2 series on their own, under observation by the trainer	Classes were audio-recorded and reviewed using checklists	Not reported
Smith et al,³⁴ 2011	388	Republic of Ireland: Cluster randomized 50% population low income Ireland general demographics 94.3% white non-Hispanic Mean HbA_1c 7.2%	9 peer supporter–facilitated sessions over 2 y; at mo 1, at mo 2, and every 3 mo thereafter	Usual care	Two 3-h evening training sessions conducted by research teams	Meetings were recorded	Participants attended mean of 5 peer support meetings; 18% never attended a meeting
Long et al,²⁴ 2012	77	United States: African American veterans Mean HbA_1c 9.85%	Weekly telephone calls by peer mentors; 34 mentors and 39 participants	Usual care	Single 1-h one-on-one training session	No supervision	First month, average of 4 calls/mo; by 6 mo, average of 2 calls/mo
Gagliardino et al,³⁷ 2013	198	Argentina: Hispanic, nonminority in country of residence Mean HbA_1c 7.2%	4 weekly peer educator sessions of 90–120 min initially; 1 at 6 mo followed by weekly calls for 6 mo then biweekly calls for 3 mo Additional face-to-face visits among peers and their supportees were scheduled every second month if specific issues warranted	4 weekly sessions of 90–120 min initially; 1 at 6 mo by educators	3-d intensive, structured, small group interactive course	Diabetes knowledge of participants tested with multiple-choice questionnaire	Not reported
Siminerio et al,²⁹ 2013	68	United States: white non-Hispanic ethnicity >80% Mean HbA_1c 8.65%	Same as control followed by monthly peer calls for 6 mo for diabetes self-management support	6 wk of CDE diabetes self-management education intervention	1-d peer training workshop for CDE with companion workbook-CDE then trained peers in 2-3–h small sessions	Contact logs for communications; goal selections were tracked	Average of 5.03 calls per participant by peer supporter lasting approximately 25–30 min
Thom et al,³⁰ 2013	299	United States: Hispanic 46.65%, African American 31.25%; coded as predominantly Hispanic Mean HbA_1c 9.95%	Telephone contacts with peers at least twice a month and 2 or more in-person contacts in 6 mo Coaches worked with median of 7 patients	Usual care	36 h of training over 8 wk in either English or Spanish	Not reported	Median of 5 (range = 0–29) interactions with the peer health coach 123 patients (83%) had at least 1 interaction; most interactions (76.6%) were by telephone, and the remainder were in person
Chan et al,³⁶ 2014	628	China: Chinese speaking 100% Mean HbA_1c 8.2%	Same as control and peer supporter telephone calls: biweekly for 3 mo, then monthly for 3 mo, and then 1 call every other month for 6 mo; anticipated 15 min per call	Comprehensive assessment, personalized report, 2-h nurse-led empowerment class, follow-up primary care visit with repeated laboratory assessment and mailing of follow-up reports	Four 8-h training sessions	Peer supporter completed and mailed checklists to document discussion items, duration of each call, and relevant remarks every 3 mo	Median of 20 calls per patient
Simmons et al,³³ 2015	644	England: Cluster randomized factorial design; white, non-Hispanic >90% Mean HbA_1c 7.3%	Peer-led group education sessions once a month for at least 5 mo and telephone/e-mail for 1:1 counseling	Usual care	Main training 14 h plus 3.5 h diabetes education session	Not reported	61.5% participants attended at least 1 education session; most participants had telephone or e-mail contacts with peers Mean number of group attendances: 3.7
Safford et al,²⁸ 2015	424	United States: cluster randomized trial; African American >90% Mean HbA_1c 7.9%	Same as control and initial 45–60–min in-person or telephone get-to-know session with peer supporter followed by weekly calls for 2 mo followed by monthly calls for 8 mo	1 h of group diabetes education class, 5-min counseling session, and diabetes report card	12 h over 2 d	Contacts documented on forms and random contacts with intervention participants	Mean number of contacts: 13.3 (SD, 8.1) 8.3% of participants had no contacts
Ayala et al,²¹ 2015	336	United States: predominantly Hispanic Mean HbA_1c 8.7%	8 telephone or in-person contacts with peer supporter in first 6 mo, then as needed contacts in the last 6 mo; 92% of participants had telephone contacts 5–8 patients per peer leader	Usual care	40–50 h	Contact logs maintained and tracked by peer leader coordinator	Median number of contacts per participant: 4 (range = 1–24) 7% received no intervention
McGowan,³⁵ 2015	361	Canada: race/ethnicity not given Mean HbA_1c 7.19%	Two participant groups received 2 varied types of peer-led self-management programs with varying components: weekly meetings for 6 wk	Usual care	24 h	Session attendance was logged	Mean attendance for intervention group: 5 sessions

CDE = certified diabetes educator; HbA_1c = hemoglobin A_1c.