Table 2.

Study rigour

Study	Study design includes pre-post intervention data	Study design includes control or comparison group	Study design includes cohort	Comparison groups equivalent at baseline on socio-demographics	Comparison groups equivalent at baseline on outcome measures	Random assignment (group or individual) to the intervention	Participants randomly selected for assessment	Control for potential confounders	Follow-up rate ≥ 75%	Total rigour score (min score = 1; max score = 9)
Allen, Serufilira, 1992 [22]	Yes	No	Yes	N/A	N/A	No	Yes	N/A	Yes	4
Allen, 1993 [23]	Yes	No	Yes	N/A	N/A	No	Yes	No	Yes	4
Allen, Tice, 1992 [24]	Yes	No	Yes	N/A	N/A	No	No	N/A	Yes	3
Anderson, 2004 [25]	Yes	No	No	No	N/A	No	No	Yes	N/A	2
Bentley, 1998 [26]	Yes	No	Yes	N/A	N/A	No	No	N/A	Yes	3
Bhave, 1995 [27]	Yes	Yes	Yes	Yes	Yes	No	No	No	Yes	6
Cartoux, 1999 [28]	No	Yes	No	N/A	N/A	No	No	No	N/A	1
Chamot, 1999 [29]	Yes	Yes	Yes	NR	N/A	No	No	Yes	Yes	5
Chandisarewa, 2007 [30]	Yes	Yes	No	N/A	N/A	No	No	No	N/A	2
Clark, 1998 [31]	Yes	No	Yes	N/A	N/A	No	Yes	No	Yes	4
Creanga, 2007 [32]	No	Yes	No	N/A	N/A	No	No	Yes	N/A	2
Coyne, 2007 [33]	Yes	Yes	No	N/A	N/A	No	No	No	N/A	2
Farquhar, 2004 [34]	Yes	Yes	Yes	No	Yes	No	No	Yes	No	5
Ghys, 2002 [35]	Yes	No	No	N/A	N/A	No	No	Yes	N/A	2
Hamlyn, 2007 [36]	Yes	Yes	No	No	N/A	No	No	No	N/A	2
Jones, 2004 [37]	Yes	Yes	Yes	Yes	Yes	Yes	No	No	Yes	7
Jones, 2006 [38]	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	8
Khoshnood, 2006 [39]	Yes	Yes	Yes	No	NR	No	No	Yes	Yes	5
Kiarie, 2006 [40]	Yes	No	Yes	N/A	N/A	No	No	No	Yes	3
King, 1995 [41]	Yes	No	Yes	N/A	N/A	No	No	N/A	Yes	3
Kissinger, 1995 [42]	Yes	Yes	Yes	No	Yes	No	No	Yes	Yes	6
McCarthy, 1992 [43]	No	Yes	No	N/A	N/A	No	No	No	N/A	1
Peck, 2003 [44]	Yes	No	No	N/A	N/A	No	No	No	N/A	1
Rasch, 2006 [45]	No	Yes	No	NR	N/A	No	No	Yes	N/A	2
Richardson, 2004 [46]	Yes	Yes	Yes	No	No	Yes	No	Yes	No	5
Semrau, 2005 [47]	No	Yes	No	N/A	N/A	No	No	No	N/A	1
Sherr, 2007 [48]	Yes	Yes	Yes	NR	NR	No	No	Yes	No	4
Simpson, 1998 [49]	No	Yes	No	Yes	N/A	Yes	No	No	N/A	3
Sirivongrangson, 2006 [50]	No	Yes	No	N/A	N/A	No	No	N/A	N/A	1
Stringer, 2007 [51]	Yes	Yes	Yes	Yes	NR	Yes	No	No	No	5
Stringer, 2001 [52]	Yes	Yes	No	No	N/A	No	No	Yes	N/A	3
Stringer, 2003 [53]	No	Yes	No	Yes	N/A	Yes	No	No	Yes	4
Van't Hoog, 2005 [54]	Yes	No	No	N/A	N/A	No	No	No	N/A	1
Wingood, 2004 [55]	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	8
Xu, 2002 [56]	Yes	No	Yes	N/A	N/A	No	No	N/A	Yes	3

N/A: not applicable; NR: not reported