{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:00:13Z","timestamp":1760238013830,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,6,30]],"date-time":"2020-06-30T00:00:00Z","timestamp":1593475200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ricerca Corrente","award":["Italian Ministry of Health to IRCCS Policlinico San Donato"],"award-info":[{"award-number":["Italian Ministry of Health to IRCCS Policlinico San Donato"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>It has been suggested that a viable strategy to improve complexity estimation based on the assessment of pattern similarity is to increase the pattern matching rate without enlarging the series length. We tested this hypothesis over short simulations of nonlinear deterministic and linear stochastic dynamics affected by various noise amounts. Several transformations featuring a different ability to increase the pattern matching rate were tested and compared to the usual strategy adopted in sample entropy (SampEn) computation. The approaches were applied to evaluate the complexity of short-term cardiac and vascular controls from the beat-to-beat variability of heart period (HP) and systolic arterial pressure (SAP) in 12 Parkinson disease patients and 12 age- and gender-matched healthy subjects at supine resting and during head-up tilt. Over simulations, the strategies estimated a larger complexity over nonlinear deterministic signals and a greater regularity over linear stochastic series or deterministic dynamics importantly contaminated by noise. Over short HP and SAP series the techniques did not produce any practical advantage, with an unvaried ability to discriminate groups and experimental conditions compared to the traditional SampEn. Procedures designed to artificially increase the number of matches are of no methodological and practical value when applied to assess complexity indexes.<\/jats:p>","DOI":"10.3390\/e22070724","type":"journal-article","created":{"date-parts":[[2020,6,30]],"date-time":"2020-06-30T09:04:59Z","timestamp":1593507899000},"page":"724","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Are Strategies Favoring Pattern Matching a Viable Way to Improve Complexity Estimation Based on Sample Entropy?"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6720-9824","authenticated-orcid":false,"given":"Alberto","family":"Porta","sequence":"first","affiliation":[{"name":"Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy"},{"name":"Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2997-2121","authenticated-orcid":false,"given":"Jos\u00e9 Fernando","family":"Valencia","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Universidad de San Buenaventura, Cali 760033, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3396-6883","authenticated-orcid":false,"given":"Beatrice","family":"Cairo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5346-2677","authenticated-orcid":false,"given":"Vlasta","family":"Bari","sequence":"additional","affiliation":[{"name":"Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5360-3137","authenticated-orcid":false,"given":"Beatrice","family":"De Maria","sequence":"additional","affiliation":[{"name":"IRCCS Istituti Clinici Scientifici Maugeri, 20138 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesca","family":"Gelpi","sequence":"additional","affiliation":[{"name":"Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8283-1988","authenticated-orcid":false,"given":"Franca","family":"Barbic","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, IRCCS Humanitas Clinical and Research Center, Humanitas University, 20089 Rozzano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raffaello","family":"Furlan","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, IRCCS Humanitas Clinical and Research Center, Humanitas University, 20089 Rozzano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,30]]},"reference":[{"key":"ref_1","first-page":"H151","article-title":"Assessment of autonomic function in humans by heart-rate spectral-analysis","volume":"248","author":"Pomeranz","year":"1985","journal-title":"Am. 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