The Use of Digitally Assessed Stress Levels to Model Change Processes in CBT - A Feasibility Study on Seven Case Examples

HEHLMANN, MIRIAM I.; SCHWARTZ, BRIAN; LUTZ, TERESA; GÓMEZ PENEDO, JUAN MARTÍN; RUBEL, JULIAN A.; LUTZ, WOLFGANG

Frontiers in Psychiatry

Frontiers

Año: 2021 vol. 12

In psychotherapy research, the measurement of treatment processes and outcome arepredominantly based on self-reports. However, given new technological developments,other potential sources can be considered to improve measurements. In a feasibilitystudy, we examined whether Ecological Momentary Assessments (EMA) using digitalphenotyping (stress level) can be a valuable tool to investigate change processesduring cognitive behavioral therapy (CBT). Seven outpatients undergoing psychologicaltreatment were assessed using EMA. Continuous stress levels (heart rate variability)were assessed via fitness trackers (Garmin) every 3min over a 2-week time period(6,720 measurements per patient). Time-varying change point autoregressive (TVCP-AR)models were employed to detect both gradual and abrupt changes in stress levels.Results for seven case examples indicate differential patterns of change processes instress. More precisely, inertia of stress level changed gradually over time in one of theparticipants, whereas the other participants showed both gradual and abrupt changes.This feasibility study demonstrates that intensive longitudinal assessments enriched bydigitally assessed stress levels have the potential to investigate intra- and interindividualdifferences in treatment change processes and their relations to treatment outcome.Further, implementation issues and implications for future research and developmentsusing digital phenotyping are discussed.