Table 1 Characteristics of included studies

Mutual Support

Edmundson 1982 [51]

Florida USA

80

N/R

N/R

N/R

N/R

N/R

Kaplan 2011 [47]^ψ

Pennsylvania USA

300

22% SS 78% mood

47

66%

13%

64%

Rogers 2007 [42]

Multiple sites USA

1827

50% SS 44% mood

43

60%

43%

29%

Segal 2011 [49]

California USA

162

41% SS 59% mood

37

54%

13%

4%

Peer Support

Barbic 2009 [39]

Ontario CA

33

79% SS 21% BPD

45

33%

N/R

12%

Chinman 2013 [36]

South Western USA

282^α

53

11%

46%

N/R

Cook 2012 [46]

Tennessee, USA

428

21% SS 40% BPD 18% mood

43

56%

54%

9%

Cook 2011 [45]

Ohio USA

555

20% SS 26% BPD, 24% MDD

46

66%

37%

15%

Craig 2004 [38]

London UK

45

100% SS

38

33%

N/R

N/R

Davidson 2004 [41]

Connecticut USA

260

50% SS 34% mood

42

57%

18%

20%

Proudfoot 2012 [37]

New South Wales Australia

407

100% BPD

N/R

70%

N/R

N/R

Rivera 2007 [48]

New York USA

255

48% SS 26% BPD 22% MDD

38

49%

71%

N/R

Simon 2011 [27]

USA

118

100% BPD

N/R

72%

19%

N/R

Sledge 2011 [44]

Connecticut USA

89

69% SS 31% mood

41

49%

N/R

N/R

Van Gestel-Timmermans 2012 [50]

Netherlands

333

33% SS

44

66%

N/R

N/R

Peer Delivered Services

Sells 2006 [43]

Connecticut USA

137

61% SS 70% multiple

42

39%

11%

N/R

Clarke 2000 [40]

Oregon USA

178

60% SS31% SM

37

39%

18%

N/R

Solomon 1995 [28]

Pennsylvania USA

96

82% SS 12% mood

41

47%

37%

N/R