Text message intervention improves objective sleep hours among adolescents: the moderating role of race-ethnicity

Objectives This 10-day study aimed to (1) assess the effectiveness of a text message–based sleep intervention and (2) determine whether the intervention was equally effective for non-Hispanic whites and racial-ethnic minority adolescents. Participants Participants were 46 (50% female) adolescents (13-18 years; mean = 15.75 years old, SD = 0.98) from a public high school in the Midwest. Intervention Participants were randomly assigned to a control or text message intervention condition. Only participants in the intervention condition received 2 text messages outlining individualized bedtime goals daily, for 8 weekdays. Measurements All participants attended a sleep lecture, wore a sleep monitor, and completed baseline and exit surveys that assessed demographics, subjective sleep, lifestyle, and psychosocial adjustment variables. Results Results of a 2 (intervention, control) × 2 (pre-intervention, postintervention) analysis of variance test revealed no significant intervention × time interaction effect (F_1,38 = 0.020, P = .889) in the full sample. This effect, however, was significantly moderated by race-ethnicity: Results indicated a significant intervention × time × race interaction (F_1,36 = 8.050, P = .007, partial η² = .183) such that the intervention significantly improved sleep hours (by approximately 1 hour) only among non-Hispanic whites (and not among adolescents of racial-ethnic minority status). Conclusions Adolescents from racial-ethnic minority groups may face significant barriers that interfere with their ability to successfully alter their sleep-wake patterns and maximize sleep hours.