{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T14:12:54Z","timestamp":1789740774456,"version":"4.0.1"},"reference-count":40,"publisher":"Human Kinetics","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,6,1]]},"abstract":"<jats:p>Spatiotemporal gait kinematics and their variability are commonly assessed in clinical and laboratory settings to quantify fall risk. Although the Hawthorne effect, or modifications in participant behavior due to knowledge of being observed, has the potential to impact such assessments, it has received minimal attention in the study of gait\u2014particularly gait variability. The purpose of this study was to quantify the Hawthorne effect on variability and central tendency measures of fall-related spatiotemporal gait parameters. Seventeen healthy young adults walked on a treadmill at a self-selected velocity for 2\u00a0minutes under covert evaluation (ie,\u00a0without awareness of being evaluated) and 2\u00a0minutes under overt evaluation. The movement was recorded using motion capture technology, from which we calculated mean value and step-to-step variability (using\u00a0standard deviation and mean absolute deviation) of step length, step width, percent double support, percent stance phase, and stride time. Although central tendencies were unaffected by evaluation type, four-of-five measures of variability were significantly lower during overt evaluation for at least one-of-two metrics. Our results suggest a Hawthorne effect on locomotor control. Researchers should be aware of this phenomenon when designing research studies and interpreting gait assessments.<\/jats:p>","DOI":"10.1123\/jab.2022-0185","type":"journal-article","created":{"date-parts":[[2023,4,6]],"date-time":"2023-04-06T16:29:54Z","timestamp":1680798594000},"page":"151-156","source":"Crossref","is-referenced-by-count":8,"title":["Variability of Spatiotemporal Gait Kinematics During Treadmill Walking: Is There a Hawthorne Effect?"],"prefix":"10.1123","volume":"39","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7432-3043","authenticated-orcid":true,"given":"Saaniya","family":"Farhan","sequence":"first","affiliation":[{"name":"Center for Lower Extremity Ambulatory Research (CLEAR), Dr. William M. Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA"},{"name":"Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5724-0919","authenticated-orcid":true,"given":"Marco A.","family":"Avalos","sequence":"additional","affiliation":[{"name":"Center for Lower Extremity Ambulatory Research (CLEAR), Dr. William M. Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3901-7961","authenticated-orcid":true,"given":"Noah J.","family":"Rosenblatt","sequence":"additional","affiliation":[{"name":"Center for Lower Extremity Ambulatory Research (CLEAR), Dr. William M. 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