MEMO: an mHealth intervention to prevent the onset of depression in adolescents: a double-blind, randomised, placebo-controlled trial.

Background: Depression often starts in adolescence making it an ideal time to intervene. We developed a universal cognitive behavioural therapy-based programme (MEMO CBT) to be delivered via multimedia mobile phone messages for teens.

Methods: We conducted a prospective multicentre, randomised, placebo-controlled superiority trial in 15 high schools in Auckland, New Zealand, comparing MEMO CBT with a control programme [MEMO control] matched for intensity and type of message but with alternative content not targeting depression. The primary outcome was the change in score on the Children's Depression Rating Scale-Revised from baseline to 12 months. Secondary outcomes included the change in scores in the self-reported Reynold's Adolescent Depression Rating Scale-Second Edition, the Moods and Feelings Questionnaire, suicidal ideation using selected items from the Youth Risk Behaviour Survey, the Pediatric Quality of Life questionnaire, 12-month period prevalence of the diagnosis of depressive disorder using the Kiddie-Schedule for Affective Disorders and Schizophrenia, and students' ratings of their satisfaction with the programme.

Results: Eight hundred and fifty-five students (13-17 years old, mean 14.3 years) were randomly assigned to MEMO CBT (426) or to MEMO Control (429). Participants (68% female) had a mean CDRS-R at baseline of 21.5 (SD: 5). Overall 394 (93%) from the intervention group and 392 (91%) from the control group were followed up at 12 months. At the end of the intervention (approximately 9 weeks) the mean CDRS-R scores were 20.8 in the intervention group versus 20.4 in the control group, and at 12 months they were 22.4 versus 22.4 (p value for difference in change from baseline = 0.3). There was no obvious association between the amount of the intervention viewed by participants and outcomes.

Conclusions: There was no evidence of benefit from the mobile phone CBT intervention compared with a control programme. Universal depression prevention remains a challenge.