Efficacy and moderators of psychological interventions in treating subclinical symptoms of depression and preventing major depressive disorder onsets protocol for an individual patient data meta-analysis of randomised controlled trials - Ebert, David D.; Buntrock, Claudia; Reins, Jo Annika; Zimmermann, Johannes; Cuijpers, Pim (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2018)