{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T18:20:00Z","timestamp":1787768400192,"version":"build-2784847793"},"reference-count":17,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T00:00:00Z","timestamp":1787702400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IU International University of Applied Sciences","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n Introduction<\/jats:title>\n German Digital Health Applications (DiGAs) are reimbursable, patient-facing digital interventions within the German healthcare system that must demonstrate positive healthcare effects. Outcome measurement in DiGA evaluations is influenced by both methodological considerations and feasibility requirements in real-world care settings. In practice, these evaluations may be affected by factors such as limited patient adherence, high dropout rates, and variability in real-world data quality, which can complicate outcome data collection. Single-item scales may offer a low-burden alternative to multi-item instruments; however, their use, justification, and limitations in DiGA evaluations have not been comprehensively mapped. This paper presents a scoping review protocol designed to address this gap.<\/jats:p>\n <\/jats:sec>\n \n Methods and analysis<\/jats:title>\n This protocol outlines a scoping review that will follow the Joanna Briggs Institute methodology and be reported in accordance with PRISMA-ScR guidelines. The review will apply the PCC framework, focusing on DiGAs listed in the BfArM DiGA directory, the use of single-item scales, and evaluations conducted within the German healthcare system. Studies will be identified primarily through the DiGA directory and supplemented by PubMed searches to verify and complete bibliographic information. Two reviewers will independently screen and verify extracted data. Quantitative data will be summarized descriptively, while qualitative information on constructs, rationales, and methodological considerations will be analyzed thematically.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n As this is a protocol, no results are reported. The planned review will provide a descriptive overview of single-item scale use in DiGA evaluations, map the constructs assessed, and identify methodological characteristics and gaps.<\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n This protocol outlines a transparent and reproducible approach to mapping outcome measurement practices in DiGAs. The findings of the completed review will inform researchers, developers, and policymakers and support methodological development in regulated digital health contexts.<\/jats:p>\n <\/jats:sec>\n \n Registration<\/jats:title>\n \n The scoping review protocol is registered at the Open Science Framework under the following DOI\n https:\/\/doi.org\/10.17605\/OSF.IO\/A3PM5<\/jats:ext-link>\n .\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0356485","type":"journal-article","created":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T17:42:30Z","timestamp":1787766150000},"page":"e0356485","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Use of single-item scales in the evaluation of German digital health applications (DiGAs): Scoping review protocol"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1246-7591","authenticated-orcid":true,"given":"Julian","family":"Wienert","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahin","family":"Mohammadi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,26]]},"reference":[{"key":"pone.0356485.ref001","unstructured":"Bundesinstitut f\u00fcr Arzneimittel und Medizinprodukte BfArM. Digital health applications (DiGA). 2026."},{"key":"pone.0356485.ref002","doi-asserted-by":"crossref","DOI":"10.1017\/S0266462322001805","article-title":"PP39 Evidence Generation For Reimbursement Of Digital Health Applications (DiGAs) In Germany","volume":"38","author":"N Fujita-Rohwerder","year":"2022","journal-title":"Int J Technol Assess Health Care"},{"issue":"1","key":"pone.0356485.ref003","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1038\/s41746-025-01879-6","article-title":"Healthcare effects and evidence robustness of reimbursable digital health applications in Germany: a systematic review","volume":"8","author":"K Sippli","year":"2025","journal-title":"NPJ Digit Med"},{"key":"pone.0356485.ref004","doi-asserted-by":"crossref","first-page":"35","DOI":"10.21037\/mhealth-23-17","article-title":"Digital health applications from a government-regulated directory of reimbursable health apps in Germany-a systematic review for evidence and bias","volume":"9","author":"F Dittrich","year":"2023","journal-title":"Mhealth"},{"issue":"2","key":"pone.0356485.ref005","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1007\/s11136-005-0887-2","article-title":"Assessing measurement properties of two single-item general health measures","volume":"15","author":"KB DeSalvo","year":"2006","journal-title":"Qual Life Res"},{"issue":"17","key":"pone.0356485.ref006","doi-asserted-by":"crossref","first-page":"5217","DOI":"10.3390\/jcm13175217","article-title":"Single-Item Assessment of Quality of Life: Associations with Well-Being, Mood, Health Correlates, and Lifestyle","volume":"13","author":"JC Verster","year":"2024","journal-title":"J Clin Med"},{"issue":"3","key":"pone.0356485.ref007","doi-asserted-by":"crossref","first-page":"434","DOI":"10.1007\/s11747-011-0300-3","article-title":"Guidelines for choosing between multi-item and single-item scales for construct measurement: a predictive validity perspective","volume":"40","author":"A Diamantopoulos","year":"2012","journal-title":"J of the Acad Mark Sci"},{"key":"pone.0356485.ref008","doi-asserted-by":"crossref","first-page":"1761107","DOI":"10.3389\/fdgth.2026.1761107","article-title":"Single-item measures in digital mental healthcare: a mini narrative review of challenges and opportunities","volume":"8","author":"L Staples","year":"2026","journal-title":"Front Digit Health"},{"key":"pone.0356485.ref009","doi-asserted-by":"crossref","first-page":"398","DOI":"10.1186\/1472-6963-14-398","article-title":"Single item measures of self-rated mental health: a scoping review","volume":"14","author":"F Ahmad","year":"2014","journal-title":"BMC Health Serv Res"},{"issue":"1","key":"pone.0356485.ref010","doi-asserted-by":"crossref","first-page":"183","DOI":"10.3390\/ejihpe11010015","article-title":"The Use of Single-Item Ratings Versus Traditional Multiple-Item Questionnaires to Assess Mood and Health","volume":"11","author":"JC Verster","year":"2021","journal-title":"Eur J Investig Health Psychol Educ"},{"key":"pone.0356485.ref011","volume-title":"Single item measures in psychological science","author":"MS Allen","year":"2022"},{"issue":"7","key":"pone.0356485.ref012","doi-asserted-by":"crossref","first-page":"467","DOI":"10.7326\/M18-0850","article-title":"PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation","volume":"169","author":"AC Tricco","year":"2018","journal-title":"Ann Intern Med"},{"key":"pone.0356485.ref013","article-title":"How to write a scoping review protocol: guidance and template","author":"J Lely","year":"2023","journal-title":"Open Sci Fram"},{"issue":"1","key":"pone.0356485.ref014","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1186\/s13643-023-02281-7","article-title":"Increasing the transparency of systematic reviews: presenting a generalized registration form","volume":"12","author":"OR van den Akker","year":"2023","journal-title":"Syst Rev"},{"issue":"1","key":"pone.0356485.ref015","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1080\/1364557032000119616","article-title":"Scoping studies: towards a methodological framework","volume":"8","author":"H Arksey","year":"2005","journal-title":"International Journal of Social Research Methodology"},{"key":"pone.0356485.ref016","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1186\/1748-5908-5-69","article-title":"Scoping studies: advancing the methodology","volume":"5","author":"D Levac","year":"2010","journal-title":"Implement Sci"},{"key":"pone.0356485.ref017","unstructured":"Joanna Briggs Institute. The scoping review framework. 2014."}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0356485","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T17:42:34Z","timestamp":1787766154000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0356485"}},"subtitle":[],"editor":[{"given":"Felix","family":"Bongomin","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,8,26]]},"references-count":17,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8,26]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0356485","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,26]]}}}