Outcome Domains and Measurement Instruments of Patient-relevant Improvement of Structure and Processes as a New Set of Outcomes for Evaluating and Approving Digital Health Applications: Systematic Review (Preprint)
Authors: Scheibe Madlen , Knapp Andreas , Harst Lorenz , Schmitt Jochen 
Published: January 2022

BACKGROUND

In October 2020, digital health applications (so-called DiGAs) became part of standard care for people with statutory health insurance in Germany. As a precondition for approval, DiGA manufacturers must demonstrate a positive healthcare effect for their application. This can be done by demonstrating proof of medical benefit or patient-relevant improvement of structure and processes (PISP). PISP refers to an innovative outcome core area in terms of proof of benefits and reimbursement decisions. These are subdivided into 9 outcome domains, including health literacy, facilitating access to care, and coping with illness-related difficulties in everyday life. Given the novelty of PISP, no standardized set of outcomes and outcome measurement instruments currently exists to operationalize the domains. Learning from previous evaluation studies can help operationalize and standardize PISPs for evaluation studies of digital health applications.

OBJECTIVE

This study aimed to examine the characteristics of PISPs, including outcomes and outcome measurement instruments, used in previous prospective controlled evaluation studies of DiGA-compliant digital health applications, published internationally before the Digital Health Applications Ordinance (DiGAV) of April 2020.

METHODS

We conducted a systematic review of evaluation studies published between 2015 and April 2020, via MEDLINE and Embase, complemented by forward and backward searches. Only studies assessing interventions adhering to the definition of DiGA were included. Studies applying no validated outcome measurement instruments were excluded, as were records where no controlled trials (randomized or not) were conducted or the results were not presented in German or English. Title and abstract screening, full-text-screening, and data extraction were conducted independently by two researchers and determined by discussion. The same process was applied for data extraction and qualitative synthesis.

RESULTS

Out of 2,671 references identified, 6 studies were finally included. A total of 48 outcomes were collected, of which 14 (29.2%) addressed PISP, 29 (60.4%) addressed medical benefit, and 5 (8.3%) addressed other outcomes. The outcomes corresponded to 5 of the 9 PISP outcome domains. Health literacy was the most common (7/14, 50.0%), followed by coping with illness-related difficulties in everyday life (3/14, 21.0%). A total of 13 different measurement instruments were used for PISP assessment, most of which were validated (10/14, 71.4%).

CONCLUSIONS

This review provides an overview of the characteristics of the PISPs used in previous evaluation studies of DiGA-compliant applications. It shows which outcomes and outcome measurement instruments can be used to measure PISP outcome domains. For some PISP outcome domains, knowledge is still lacking concerning the outcomes and validated outcome measurement instruments to be used. Given the small number of studies included, the results serve as a starting point for operationalizing and standardizing PISPs.