Table 3.

Within-group effect sizes and between-group effect sizes, presented as Cohen’s d [95% CI] for primary outcomes and knowledge at each assessment point.

	BAI	Measure		Knowledge test, Weighted score
		BDI	Knowledge test Raw score
Between-group effect sizes pre to post treatment
Learning support vs no learning support
Completers	0.41 [0.05, 0.77]	0.37 [0.01, 0.73]	0.46 [0.09, 0.82]	0.49 [0.12, 0.85]
ITT	0.38 [0.01, 0.73]	0.34 [-0.02, 0.70]	0.38 [0.01, 0.74]	0.42 [0.06, 0.78]
Chat-sessions vs no chat-sessions
Completers	0.24 [-0.60, 0.12]	0.03 [-0.33, 0.39]	0.12 [-0.48, 0.24]	0.10 [-0.25, 0.46]
ITT	0.23 [-0.59, 0.13]	0.04 [-0.32, 0.39]	0.02 [-0.38, 0.36]	0.02 [-0.34, 0.38]
Within-group effect sizes pre to post treatment
Standard ICBT
Completers	0.59 [0.06, 1.11]	0.77 [0.22, 1.30]	0.92 [0.37,1.45]	1.32 [0.73, 1.86]
ITT	0.63 [0.10, 1.13]	0.75 [0.22-1.26]	0.80 [0.27, 1.32]	1.34 [0.77, 1.88]
Learning support
Completers	1.04 [0.48, 1.58]	1.48 [0.87, 2.04]	1.14 [0.56, 1.68]	1.72 [1.08, 2.31]
ITT	0.98 [0.44, 1.51]	1.33 [0.75, 1.87]	1.11 [0.55, 1.64]	1.68 [1.07, 2.25]
Standard ICBT with chat
Completers	0.63 [0.09, 1.15]	0.77 [0.22, 1.30]	0.63 [0.10, 1.15]	1.14 [0.57-1.69]
ITT	0.66 [0.13, 1.17]	0.79 [0.26, 1.31]	0.66 [0.13, 1.17]	1.16 [0.60, 1.69]
Learning support with chat
Completers	0.94 [0.35, 1.50]	1.56 [0.92, 2.15]	1.02 [0.43, 1.59]	2.10 [1.39, 2.74]
ITT	0.85 [0.21, 1.36]	1.39 [0.81, 1.94]	1.02 [0.47, 1.55]	1.88 [1.25, 2.47]
Between-group effect sizes pre to 6 month follow-up
Learning support vs no learning support
Completers	-0.14 [-0,56, 0.62]	-0.29 [-0.71, 0.14]	-0.05 [-0.48, 0.37]	0.01 [-0.43, 0.42]
ITT	-0.09 [-0.27, 0.44]	-0.20 [-0.56, 0.16]	-0.07 [-0.43, 0.29]	0.01 [-0.37, 0.34]
Chat-sessions vs no chat-sessions
Completers	0.20 [-0.23, 0.62]	0.01 [-0.41, 0.44]	0.14 [-0.29, 0.56]	0.10 [-0.25, 0.46]
ITT	0.14 [-0.22, 0.50]	0.02 [-0.33, 0.38	0.12 [-0.24, 0.48]	0.02 [-0.34, 0.38]
Within-group effect sizes post treatment to 6 months follow-up
Standard ICBT
Completers	0.40 [-0.17, 0.96]	0.21 [-0.36, 0.77]	0.25 [-0.32, 0.81]	0.35 [-0.22, 0.92]
ITT	0.38 [-0.14, 0.88]	0.26 [-0.76, 0.25]	0.29 [-0.22, 0.80]	0.00 [-0.51, 0.51]
Learning support
Completers	0.07 [-0.50, 0.64]	0.22 [-0.36, 0.79]	0.17 [-0.40, 0.74]	0.33 [-0.25, 0.90]
ITT	0.09 [-0.41, 0.60]	0.03 [-0.54, 0.47]	0.21 [-0.30, 0.74]	0.28 [-0.23, 0.79]
Standard ICBT with chat
Completers	0.45 [-0.12, 0.01]	0.30 [-0.27, 0.87]	0.34 [-0.25, 0.91]	0.26 [-0.84, 0.32]
ITT	0.33 [-0.83, 0.18]	0.16 [-0.35, 0.67]	0.10 [-0.41, 0.61]	0.20 [-0.31, 0.71]
Learning support with chat
Completers	0.22 [-0.35, 0.78]	0.32 [-0.28, 0.91]	0.15 [-0.76, 0.46]	0.00 [-0.61, 0.61]
ITT	0.19 [-0.69, 0.32]	0.22 [-0.29, 0.73]	0.14 [-0.37, 0.64]	0.05 [-0.45, 0.56]

BAI, Beck Anxiety Inventory; BDI, Beck Depression Inventory.