Objective: The Transdiagnostic Sleep and Circadian Intervention for Youth (TranS-C) was developed to improve sleep and circadian functioning in adolescents. This study examined the 12-month effects for TranS-C compared with psychoeducation (PE). We also investigated whether a text messaging intervention can promote maintenance of treatment effects.
Method: At the baseline, adolescents (58% female, average age = 14.8 years) with an eveningness chronotype were randomized to TranS-C (n = 89) or PE (n = 87). At 6-month follow-up, participants were randomized to receive text messages that had repeated treatment information (n = 47), text messages that prompted the recall of treatment information (n = 50), or no text messages (n = 47).
Results: Relative to PE, TranS-C was associated with a reduced eveningness (b = 2.06, p = .005, d = 0.29) from the baseline to a 12-month follow-up. TranS-C treatment effects, relative to PE, were augmented by receiving text messages, compared to no text messages, for eveningness from baseline to 12-month follow-up (b = 1.38, p = .008, d = 0.28) and from 6- to 12-month follow-up (b = 1.07, p = .046, d = 0.21). Neither TranS-C nor text messages were significantly associated with other primary outcomes. TranS-C and text messages were significantly associated with improvements on selected secondary sleep and health outcomes through follow-up.
Conclusions: For adolescents with an eveningness chronotype, improved sleep and circadian functioning on selected outcomes were maintained over 12 months for TranS-C compared with PE. Text messages boosted the effects of TranS-C through 12-month follow-up.