Abstract
In Germany, statutory health insurance reimburses digital health applications (DiGAs) approved by the Federal Institute for Drugs and Medical Devices (BfArM). Permanent approval requires evidence of positive healthcare effects, either medical benefits or patient-relevant improvements in structures and processes (pSVV). This systematic review analyzed all 23 DiGA approval studies available as of March 15, 2024. The studies, conducted between 2012 and 2022, included 56 to 1245 participants and intervention durations from 1.5 to 12 months. Drop-out rates varied (mean 21.7% in intervention, 11.8% in control group). Most studies (13/23) focused on primary outcomes related to mental health conditions; one addressed pSVV. All reported significant medium to large effects, but risk of bias was high, particularly in outcome measurement (21/23) and due to missing data (15/23). These findings raise concerns about the robustness of the evidence supporting DiGA efficacy. The review recommends revising the DiGA approval process to enhance study quality. The systematic review was registered prospectively with PROSPERO https://www.crd.york.ac.uk/prospero/ (CRD42023460497).