Digital health tools for the passive monitoring of depression: a systematic review of methods. - Valeria de Angel; Serena Lewis; Katie M. White; Carolin Oetzmann; Daniel Leightley; Emanuela Oprea; Grace Lavelle; Faith Matcham; Alice Pace; David C. Mohr; Richard J. B. Dobson; Matthew Hotopf (npj Digit. Medicine, 2022)