{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T02:39:59Z","timestamp":1777430399942,"version":"3.51.4"},"reference-count":24,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T00:00:00Z","timestamp":1580169600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T00:00:00Z","timestamp":1580169600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J Orthop Traumatol"],"published-print":{"date-parts":[[2020,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n<jats:title>Background<\/jats:title>\n<jats:p>The placebo effect can account for part of the improvement seen in patients undergoing any type of treatment, be it surgical or pharmacological. The objective of this study is to quantify the placebo effect in carpal tunnel syndrome treatment.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Materials and methods<\/jats:title>\n<jats:p>A double-blinded randomized trial was performed with 68 patients suffering from mild to moderate carpal tunnel syndrome, divided into two groups with no statistically significant differences regarding age, weight, or degree of nerve compression. The patients were evaluated clinically and electromyographically before and after 2\u00a0months of treatment with either palmitoylethanolamide (PEA) or placebo.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>The results, comparing the two groups, showed an improvement in both groups on a visual analogue scale (VAS) and Levine\u2019s questionnaire, which have been reported to show statistical differences in only a few items. In the placebo group, the mean age was 53.32\u00a0years (\u00b113.43) and the BMI was 28.85\u00a0kg\/m<jats:sup>2<\/jats:sup> (\u00b14.84). Before treatment, the average symptom severity score (SSS) on the Levine questionnaire was 2.57 (\u00b10.74) and the functional status score (FSS) was 2.24 (\u00b10.66). After treatment, these decreased to 2.11 (\u00b10.81) and 1.96 (\u00b10.77), being statistically nonsignificant for SSS (<jats:italic>p<\/jats:italic>\u2009=\u20090.0865) but significant for FSS (<jats:italic>p<\/jats:italic>\u2009=\u20090.0028). VAS showed a statistically nonsignificant decrease from 4.06 to 3.25 (<jats:italic>p<\/jats:italic>\u2009=\u20090.3407). After placebo treatment, SSS, FSS, and VAS improved by 0.46, 0.28, and 0.81 points or 17.89%, 12.5%, and 19.95%, respectively.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Conclusions<\/jats:title>\n<jats:p>These results show an improvement in the studied parameters by up to 20%, but when compared with those published in literature, these show great variability due to the wide variety of factors involved in the placebo effect. Several factors that affect the placebo effect are discussed, and the present work tries to quantify it in carpal tunnel syndrome.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Level of Evidence<\/jats:title>\n<jats:p>Level 2 of evidence according to \u201cThe Oxford 2011 Level of Evidence.\u201d<\/jats:p>\n<\/jats:sec>","DOI":"10.1186\/s10195-019-0540-4","type":"journal-article","created":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T12:03:43Z","timestamp":1580213023000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Measuring the placebo effect in carpal tunnel syndrome"],"prefix":"10.1186","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6141-7764","authenticated-orcid":false,"given":"Jordi","family":"Faig-Mart\u00ed","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adriana","family":"Mart\u00ednez-Catass\u00fas","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2020,1,28]]},"reference":[{"issue":"4","key":"540_CR1","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1016\/j.pmn.2010.10.033","volume":"12","author":"P Arnstein","year":"2011","unstructured":"Arnstein P, Broglio K, Wuhrman E, Kean MB (2011) Use of placebos in pain management. 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The institutional review board and ethical committee approved this study, and it was registered in our hospital\u2019s clinical trial registry.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"All authors of the manuscript have read and agreed to its content and are accountable for all aspects of the accuracy and integrity of the manuscript in accordance with ICMJE criteria. The article is original, has not already been published in a journal, and is not currently under consideration by another journal. All authors agree to the terms of the SpringerOpen Copyright and License Agreement.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"1"}}