{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T19:05:32Z","timestamp":1789671932263,"version":"4.0.1"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T00:00:00Z","timestamp":1760486400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007155","name":"Medical Research Council","doi-asserted-by":"publisher","award":["UKRI\/MR\/B000091\/1"],"award-info":[{"award-number":["UKRI\/MR\/B000091\/1"]}],"id":[{"id":"10.13039\/501100007155","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Innovative Medicines Initiative 2 Joint Undertaking","award":["853981"],"award-info":[{"award-number":["853981"]}]},{"name":"European Union\u2019s Horizon 2020 research and innovation program"},{"name":"National Institute for Health Research (NIHR) Newcastle Biomedical Research Centre"},{"name":"UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council","award":["EP\/X031012\/1"],"award-info":[{"award-number":["EP\/X031012\/1"]}]},{"name":"UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council","award":["EP\/X036146\/1"],"award-info":[{"award-number":["EP\/X036146\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Digital Mobility outcomes can serve as objective biomarkers of health, but their validation in populations with multiple long-term conditions (MLTCs) based on wrist-worn devices remains unexplored. We refined, improved, and introduced novel algorithms, specifically tailored and adapted for (i) gait sequence detection, (ii) initial contact identification, and (iii) stride length estimation from a single wrist-worn device. Validation was performed using data from 28 participants with co-occurring MLTCs performing a 2.5 h real-world monitoring session. Reference data from an established multi-sensor system were used to assess algorithm performance across diverse gait patterns of co-occurring MLTCs. Twenty-eight participants (mean age 70.4 years, 43% females) had a median of three co-occurring MLTCs. Among six gait sequence detection methods, improved versions of the Kheirkhahan algorithm performed best (accuracy = 0.92, specificity = 0.96). For initial contact detection (nine methods tested), Shin\u2019s algorithm achieved the highest performance index (0.85) followed by McCamley (0.84). Stride length estimation was most accurate using novel approaches based on the Weinberg method (performance index &gt; 0.70). The proposed fine-tuned algorithms, the newly developed adaptive variants, and the foot-length augmented versions demonstrated robust performance, surpassing many existing methods and addressing the complexity of gait patterns in MLTCs. These findings enable scalable, real-time mobility monitoring in complex clinical populations using accessible wearable technology.<\/jats:p>","DOI":"10.3390\/bioengineering12101108","type":"journal-article","created":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T10:12:29Z","timestamp":1760523149000},"page":"1108","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Real-World Wrist-Derived Digital Mobility Outcomes in People with Multiple Long-Term Conditions: A Comparison of Algorithms"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6786-4346","authenticated-orcid":false,"given":"Dimitrios","family":"Megaritis","sequence":"first","affiliation":[{"name":"Faculty of Health and Life Sciences, Northumbria University Newcastle, Newcastle upon Tyne NE1 8ST, UK"},{"name":"Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE4 5PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8364-9803","authenticated-orcid":false,"given":"Lisa","family":"Alcock","sequence":"additional","affiliation":[{"name":"Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE4 5PL, UK"},{"name":"National Institute for Health and Care Research (NIHR) Newcastle Biomedical Research Centre (BRC), Newcastle University, Newcastle upon Tyne NE4 5PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7931-1424","authenticated-orcid":false,"given":"Kirsty","family":"Scott","sequence":"additional","affiliation":[{"name":"Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE4 5PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hugo","family":"Hiden","sequence":"additional","affiliation":[{"name":"School of Computing, Newcastle University, Newcastle upon Tyne NE4 5TG, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7276-5382","authenticated-orcid":false,"given":"Andrea","family":"Cereatti","sequence":"additional","affiliation":[{"name":"Department of Electronics and Telecommunications, Politecnico di Torino, 10129 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4830-7207","authenticated-orcid":false,"given":"Ioannis","family":"Vogiatzis","sequence":"additional","affiliation":[{"name":"Faculty of Health and Life Sciences, Northumbria University Newcastle, Newcastle upon Tyne NE1 8ST, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1154-4751","authenticated-orcid":false,"given":"Silvia","family":"Del Din","sequence":"additional","affiliation":[{"name":"Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE4 5PL, UK"},{"name":"National Institute for Health and Care Research (NIHR) Newcastle Biomedical Research Centre (BRC), Newcastle University, Newcastle upon Tyne NE4 5PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1186\/s12984-023-01198-5","article-title":"Assessing real-world gait with digital technology? 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