Ecological Momentary Assessments of Nighttime Drinking Among California Adolescents: Bases for Informing Nighttime Preventive Interventions

BACKGROUND AND AIM To inform the development of effective night-time preventive interventions, our goal was to assess adolescents' residence (i.e. being at) and transitions across contexts during evening hours and risks for drinking and drinking-related problems in relation to contexts and to these transitions. DESIGN Ecological momentary assessment and survey methods. SETTING Twelve mid-sized cities (50 000-500 000 population) in California, USA from December 2014 to September 2015. ANALYTICAL SAMPLE A total of 153 adolescents (mean age = 16.4, 46.2% female). MEASUREMENT Initial conditions (e.g. past-year heavy drinking, gender, best friend's approval of drinking); adolescents' residence (i.e. being at) and transitions between (a) their own homes, (b) others' homes and (c) public spaces (e.g. restaurants, parks, concert venues) at early, middle and late evening hours; drinking in these contexts at early, middle and late evening hours; and drinking-related problems across evening hours. FINDINGS Risks for drinking were 23.5 times greater in others' homes (P