Table 1. Included studies.

	Type	N	N completers (100%)	N completers (80%)	N responders to post-treatment	Sessions completed mean (SD)	Maximum amount of sessions	Country	ITT analysis
Bodenmann et al., 2008	FtF CBT	20	20	20	19	20 (0)	20	Swiss	yes
Castonguay et al., 2004	FtF CBT	14	12	NR	12	NR	20	US	no
Constantino et al., 2008	FtF CBT	11	8	8	8	14.38 (2.39)	16	US	yes
David et al., 2008	FtF CBT	56	50	NR	49	17.55 (5.51)f	20	Rom	yes
DeRubeis et al., 2005	FtF CBT	60	51	51	51	23.95 (9.72)f	28	US	yes
Dimidjian et al., 2006	FtF CBT	45	39	39	39	20.91 (7.97)f	24	US	yes
Dunlop et al., 2012	FtF CBT	41	NR	NR	NR	NR	16	US	yes
Hautzinger & Welz, 2008	FtF CBT	31	26	NR	26	NR	15	Ger	yes
McBride et al., 2006	FtF CBT	37	29	NR	28	16.56 (3.22)	20	Can	yes
Serfaty et al., 2009	FtF CBT	70	NR	NR	64	7.09 (4.41)	12	UK	yes
Strauman t al., 2006	FtF CBT	21	17	18	20	18.2 (SD NR)	NRg	US	yes
Teismann et al., 2011	FtF CBT	34	33	33	28	22.4 (3.8)	24	Ger	no
Thompson et al., 2001	FtF CBT	31	24	NR	24	NR	20	US	yes
Watson et al., 2003	FtF CBT	NR	33	NR	33	NR	16	Can	yes
Andersson et al., 2005	Guid. iCBT	57	37	NR	36	3.7 (1.9)	5	Swe	yes
Berger et al., 2011	Guid. iCBT	25	14	NR	25	8.52 (2.86)	10	Swiss/Ger	yes
Choi et al., 2012	Guid. iCBT	28	17	17	23	4.93 (1.88)	6	Aus	yes
Johansson et al., 2012a	Guid. iCBT	39	NR	NR	36	6.91 (SD NR)	8–10 (m  =  9.7)	Swe	yes
Johansson et al., 2012b	Guid. iCBT	40	NR	NR	34	5.97 (SD NR)	8	Swe	yes
Perini et al., 2009	Guid. iCBT	27	20	20	18	5.33 (1.21)	6	Aus	yes
Ruwaard et al., 2009	Guid. iCBT	36	33	NR	33	NR	8	NL	yes
Titov et al., 2010c	Guid. iCBT	43	33	35	37	5.30 (1.57)	6	Aus	yes
Titov et al., 2010d	Guid. iCBT	47	32	37	41	5.21 (1.43)	6	Aus	yes
Titov et al., 2011e	Guid. iCBT	18	NR	NR	NR	NR	8	Aus	yes
Vernmark et al., 2010	Guid. iCBT	29	17	NR	27	6 (1.58)	7	Swe	yes

Abbreviations: Guid. iCBT  =  guided internet-delivered cognitive behavioural therapy; FtF CBT  =  individual face-to-face cognitive behavioural therapy;

NR  =  not reported; SD  =  standard deviation; ITT  =  intention to treat.

^aTailored intervention group.

^bStandardised intervention group.

^cTechnician assisted.

^dClinician assisted.

^eTransdiagnostic intervention. Adherence was reported, but not specifically for the depressed group.

^fMean and standard deviation estimated.

^gParticipants completing 12 or more sessions were considered completers, but there was no maximum amount of sessions.