Table 5.

Estimated effect moderation by recent habituation and engagement.

Notification typea		Estimated notification effect		Estimated effect moderation
		Relative risk (95% CI)		Multiplicative difference in effect (95% CI)
		No	Yes	Ratio (yes or no)
Habituation—“Did the user receive a notification the day before?”
	Pooled	3.645 (2.665-4.987)	3.449 (2.761-4.308)	0.946 (0.655-1.368)
	Standard	3.935 (2.837-5.458)	3.497 (2.739-4.465)	0.889 (0.601-1.314)
	New message	3.357 (2.381-4.732)	3.401 (2.692-4.298)	1.013 (0.677-1.517)
Already engaged—“Did the user open the app between 8 PM and 9 PM the day before?”
	Pooled	3.620 (2.908-4.508)	3.168 (2.314-4.336)	0.875 (0.616-1.242)
	Standard	3.720 (2.938-4.710)	3.580 (2.542-5.043)	0.962 (0.652-1.420)
	New message	3.521 (2.794-4.439)	2.820 (2.015-3.946)	0.801 (0.548-1.168)

^aAll models are adjusted for the continuous variables of age; Alcohol Use Disorders Identification Test score; days since download; the categorical variables of sex and employment type; the time-varying variables “Did the users open the app before 8 PM that day?” and “Did the users open the app after 9 PM the day before?”; and the effect moderation variable of habituation.