Table 2.

Subgroup analysis of abstinence during the 3-month and endpoint abstinence.

Subgroup		Sample size	Risk ratio (95% CI)	Risk ratio (95% CI)
			3-month	Endpoint
Strategies used for digital interventions
	Both	7187	1.59 (1.32, 1.91)	1.43 (1.12, 1.83)
	Cognitive behavioral therapy	1547	2.99 (1.62, 5.53)	2.30 (1.28, 4.12)
	Transtheoretical model of behavior change	6321	1.48 (1.11, 1.97)	1.43 (1.12, 1.83)
	Others	417	1.70 (0.69, 4.21)	1.65 (1.26, 2.15)
	P value for subgroup difference	N/Aa	.23	.50
Sample size
	>500	13,179	1.54 (1.28, 1.86)	1.41 (1.11, 1.78)
	≤500	2293	1.98 (1.51, 2.60)	1.78 (1.34, 2.37)
	P value for subgroup difference	N/A	.13	.21
Control
	Self-help guideline	10,126	1.51 (1.26, 1.80)	1.42 (1.14, 1.76)
	No intervention	5236	2.22 (1.70, 2.91)	1.94 (1.35, 2.78)
	P value for subgroup difference	N/A	.02	.14
Intervention type
	Text-based	11,047	1.59 (1.31, 1.92)	1.48 (1.16, 1.89)
	Multiplatform-based	4425	1.85 (1.41, 2.44)	1.61 (1.24, 2.24)
	P value for subgroup difference	N/A	.36	.54
Intervention duration
	>1 month	12,308	1.70 (1.41, 2.04)	1.59 (1.28, 1.97)
	≤1 month	3164	1.89 (1.24, 2.90)	1.65 (1.00, 2.71)
	P value for subgroup difference	N/A	.64	.89
Overall		15,472	1.72 (1.46, 2.01)	1.58 (1.31, 1.90)

^aN/A: not applicable.