Transitions in Depression (TRANS-ID) Recovery: Study protocol for a repeated intensive longitudinal n= 1 study design to search for personalized early warning signals of critical transitions towards improvement in depression

The Transitions in Depression (TRANS-ID) Recovery study is aimed at gathering intensive longitudinal data in a group of depressed patients during psychological therapy. Per person, we gathered between 500-600 momentary measurements of mood (5 times a day, for 4 months) using the Experience Sampling Method (ESM), as well as weekly symptom checklists and heart rate and actigraphy measurements. This document describes the detailed study procedures that were employed to recruit participants, collect the data, and keep compliance high over the span of a year