{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T12:41:36Z","timestamp":1780058496970,"version":"3.54.0"},"reference-count":69,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,14]],"date-time":"2019-05-14T00:00:00Z","timestamp":1557792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Seventh Framework Programme","award":["288940"],"award-info":[{"award-number":["288940"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Physical capability (PC) is conventionally evaluated through performance-based clinical assessments. We aimed to transform a battery of sensor-based functional tests into a clinically applicable assessment tool. We used Exploratory Factor Analysis (EFA) to uncover the underlying latent structure within sensor-based measures obtained in a population-based study. Three hundred four community-dwelling older adults (163 females, 80.9 \u00b1 6.4 years), underwent three functional tests (Quiet Stand, QS, 7-meter Walk, 7MW and Chair Stand, CST) wearing a smartphone at the lower back. Instrumented tests provided 73 sensor-based measures, out of which EFA identified a fifteen-factor model. A priori knowledge and the associations with health-related measures supported the functional interpretation and construct validity analysis of the factors, and provided the basis for developing a conceptual model of PC. For example, the \u201cWalking Impairment\u201d domain obtained from the 7MW test was significantly associated with measures of leg muscle power, gait speed, and overall lower extremity function. To the best of our knowledge, this is the first time that a battery of functional tests, instrumented through a smartphone, is used for outlining a sensor-based conceptual model, which could be suitable for assessing PC in older adults and tracking its changes over time.<\/jats:p>","DOI":"10.3390\/s19102227","type":"journal-article","created":{"date-parts":[[2019,5,14]],"date-time":"2019-05-14T10:42:33Z","timestamp":1557830553000},"page":"2227","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["An Exploratory Factor Analysis of Sensor-Based Physical Capability Assessment"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3317-6200","authenticated-orcid":false,"given":"Alice","family":"Coni","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic and Information Engineering \u201cGuglielmo Marconi\u201d (DEI), University of Bologna, 40136 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7688-0188","authenticated-orcid":false,"given":"Sabato","family":"Mellone","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic and Information Engineering \u201cGuglielmo Marconi\u201d (DEI), University of Bologna, 40136 Bologna, Italy"},{"name":"Health Sciences and Technologies -Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco","family":"Colpo","sequence":"additional","affiliation":[{"name":"Geriatric Unit, Local Health Unit Tuscany Centre, 40125 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jack M.","family":"Guralnik","sequence":"additional","affiliation":[{"name":"Division of Gerontology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8443-2876","authenticated-orcid":false,"given":"Kushang V.","family":"Patel","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology &amp; Pain Medicine, University of Washington, Seattle, WA 98195, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefania","family":"Bandinelli","sequence":"additional","affiliation":[{"name":"Geriatric Unit, Local Health Unit Tuscany Centre, 40125 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2318-4370","authenticated-orcid":false,"given":"Lorenzo","family":"Chiari","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic and Information Engineering \u201cGuglielmo Marconi\u201d (DEI), University of Bologna, 40136 Bologna, Italy"},{"name":"Health Sciences and Technologies -Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1093\/ageing\/afq117","article-title":"Objective measures of physical capability and subsequent health: A systematic review","volume":"40","author":"Cooper","year":"2011","journal-title":"Age Ageing"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.maturitas.2013.07.007","article-title":"Towards measurement of the Healthy Ageing Phenotype in lifestyle-based intervention studies","volume":"76","author":"Lara","year":"2013","journal-title":"Maturitas"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"van Lummel, R.C., Walgaard, S., Pijnappels, M., Elders, P.J.M., Garcia-Aymerich, J., van Die\u00ebn, J.H., and Beek, P.J. 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