Table 2 Characteristics of the included studies: characteristics of peer support, frequency, length and theory basis of intervention, and description of usual care group

Thom 2013 [35]

Peer coach

T2DM who had an HbA1c level of less than 8.5% within the past 6 months

36-hour

Individual (telephone contact and in-person contact)

High

6 months

None

Usual care included all services usually available to patients, including access to a nutritionist and diabetes educator through referral from their primary care clinician.

Dang 2013 [36]

Peer coach

T2DM for one year or more, 30 years old or older, and with HbA1c level in the most recent three months equal to or less than 7%.

Four sessions

Individual (telephone contact)

Moderate

6 months

Social cognitive theory

Follow up at the diabetes outpatient clinic on different dates from the participants in the intervention group to prevent subject contamination.

Prezio 2013 [37]

CHW

Adult female lifelong member of the local Mexican American community, with a high school equivalency (General Educational Development: GED) and certification from the State of Texas as a CHW.

27 h

Individual

Low

12 months

Social cognitive theory

Usual medical care.

Long 2012 [38]

Peer coach or mentors

Diabetes patients whose glucose control had previously been poor but was currently good.

1 hour

Individual (telephone contact)

Low

6 months

Motivational interviewing techniques

Usual care.

Spencer 2011 [39]

CHW

Family health advocates, from the 2 participating communities, where they were ethnically matched with their assigned participants

more than 80 hours

Both

High

6 months

Motivational interviewing and Empowerment theory

Usual care.

Smith 2011 [17]

Peer supporter

T2DM for at least one year; adherent to treatment and behavior change regimens; Capacity and commitment to undergo the training required etc.

Two evening training sessions

Group

Low

24 months

Social support theory

Provided regular recall of patients every three to six months with an annual audit of risk factors.

Lorig 2009 [18]

Peer leaders

Age from 35 to 70 years and came from the same communities as the participants. Most had type 2 diabetes and were not health professionals

4 days

Group

Low

6 months

None

Usual care was representative of care received in urban areas.

Lorig 2008 [40]

Peer leader

Spanish-speaking peer leaders came from the same communities as the participants most had type 2 diabetes and were not health professionals

4 days

Group

Moderate

6 months

None

Usual care.

Murrock 2009 [41]

Peer coach

NR

NR

Group

High

3 months

Social cognitive theory

Usual care group continued with their normal daily routines, medication schedule, diet, and glucose-monitoring regimen.

Philis-Tsimikas 2011 [42]

Peer educators

Individuals with diabetes who exemplified the traits of a natural leader were identified from the patient population and trained as promotoras over a 3-month period

40 h learning, 2 series of classes and then finally taught two series on their own.

Group

High

10 months

None

Usual care.

Lujan 2007 [43]

Peer promotoras

NR

60 hours

Group

High

6 months

Community empowerment

Usual one-on-one patient education by the clinic staff during scheduled medical follow-up visits, which consisted of verbal information and 1 or 2 pamphlets on diabetes self-management skills.

Samuel-Hodge 2009 [46]

Peer counselor

T2DM or having lived with someone diagnosed with diabetes for at least 2 years

over a 1-month period (4 weekly 4-hour sessions)

Both

High

8 months

None

Received standard educational pamphlets by mail.

Feathers 2005 [45]

CHW

African American and Latino community residents

10 weeks

Group

Low

10 months

NR

Usual care.