{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T23:12:33Z","timestamp":1776467553417,"version":"3.51.2"},"reference-count":27,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,21]],"date-time":"2021-09-21T00:00:00Z","timestamp":1632182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/2.zoppoz.workers.dev:443\/https\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Actigraphy is a well-known, inexpensive method to investigate human movement patterns. Sleep and circadian rhythm studies are among the most popular applications of actigraphy. In this study, we investigate seven common sleep-wake scoring algorithms designed for actigraphic data, namely Cole-Kripke algorithm, two versions of Sadeh algorithm, Sazonov algorithm, Webster algorithm, UCSD algorithm and Scripps Clinic algorithm. We propose a unified mathematical framework describing five of them. One of the observed novelties is that five of these algorithms are in fact equivalent to low-pass FIR filters with very similar characteristics. We also provide explanations about the role of some factors defining these algorithms, as none were given by their Authors who followed empirical procedures. Proposed framework provides a robust mathematical description of discussed algorithms, which for the first time allows one to fully understand their operation and basics.<\/jats:p>","DOI":"10.3390\/s21186313","type":"journal-article","created":{"date-parts":[[2021,9,21]],"date-time":"2021-09-21T22:35:20Z","timestamp":1632263720000},"page":"6313","update-policy":"https:\/\/2.zoppoz.workers.dev:443\/https\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["On the Unification of Common Actigraphic Data Scoring Algorithms"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0003-2598-6526","authenticated-orcid":false,"given":"Piotr","family":"Biega\u0144ski","sequence":"first","affiliation":[{"name":"Faculty of Physics, University of Warsaw, ul. Ludwika Pasteura 5, 02-093 Warsaw, Poland"},{"name":"Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, ul. Stefana Banacha 2C, 02-097 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0002-4904-2530","authenticated-orcid":false,"given":"Anna","family":"Str\u00f3\u017c","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Warsaw, ul. Ludwika Pasteura 5, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0002-8018-4342","authenticated-orcid":false,"given":"Marian","family":"Dovgialo","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Warsaw, ul. Ludwika Pasteura 5, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0002-5984-2339","authenticated-orcid":false,"given":"Anna","family":"Duszyk-Bogorodzka","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Warsaw, ul. Ludwika Pasteura 5, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0001-5816-8082","authenticated-orcid":false,"given":"Piotr","family":"Durka","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Warsaw, ul. Ludwika Pasteura 5, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1455","DOI":"10.5664\/jcsm.5288","article-title":"Consumer sleep technologies: A review of the landscape","volume":"11","author":"Ko","year":"2015","journal-title":"J. Clin. Sleep Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1093\/sleep\/26.3.342","article-title":"The role of actigraphy in the study of sleep and circadian rhythms","volume":"26","author":"Cole","year":"2003","journal-title":"Sleep"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1177\/0018720809352789","article-title":"The potential for actigraphy to be used as an indicator of sitting discomfort","volume":"51","author":"Telfer","year":"2009","journal-title":"Hum. 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