{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T04:58:59Z","timestamp":1785560339825,"version":"3.56.0"},"reference-count":71,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T00:00:00Z","timestamp":1785369600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016247","name":"Wroc\u0142aw University of Environmental and Life Sciences","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100016247","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/05cs8k179","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background: Fibromyalgia is a chronic pain syndrome in which treatment effectiveness may be influenced by biological, psychological, social, and nutritional factors. This study aimed to identify clinical, psychosocial, nutritional, and selected individual factors associated with patients\u2019 perceived overall treatment effectiveness among women with fibromyalgia. Specifically, we examined whether fibromyalgia symptom severity, psychological and social quality of life, diet quality, vitamin D3 supplementation, treatment duration, and selected individual characteristics were associated with patients\u2019 perceptions of treatment effectiveness. Methods: A cross-sectional online study included 195 women with physician-diagnosed fibromyalgia who reported using medications and\/or supplements. Fibromyalgia severity (FAS, FIQR), quality of life in psychological and social domains (WHOQOL-BREF), diet quality (pHDI, nHDI, DQI), vitamin D3 supplementation, and treatment duration were assessed. Cluster analysis and hierarchical linear regression were performed to identify factors associated with self-perceived treatment effects. Results: Women reporting lower treatment effects presented greater symptom severity, higher FIQR scores, and lower quality of life in psychological and social domains. No significant differences were observed according to age, BMI, diet quality, or self-reported daily vitamin D3 supplementation. In the final regression model, treatment duration (\u03b2 = 0.246; p &lt; 0.001), quality of life in the psychological domain (\u03b2 = 0.173; p = 0.035) and social domain (\u03b2 = 0.158; p = 0.039), and symptom severity (\u03b2 = \u22120.196; p = 0.041) independently predicted self-perceived treatment effects. Conclusions: Better psychological and social well-being, lower symptom severity, and longer treatment duration were associated with higher perceived treatment effectiveness, whereas neither diet quality nor self-reported daily vitamin D3 supplementation was associated with this outcome. These findings support a multidisciplinary biopsychosocial model of care integrating nutritional, medical, psychological, and social interventions.<\/jats:p>","DOI":"10.3390\/jcm15155956","type":"journal-article","created":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:38:54Z","timestamp":1785411534000},"page":"5956","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Determinants of Perceived Treatment Effectiveness in Women with Fibromyalgia: A Cross-Sectional Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7957-918X","authenticated-orcid":false,"given":"Robert","family":"Gajda","sequence":"first","affiliation":[{"name":"Department of Human Nutrition, Faculty of Biotechnology and Food Sciences, Wroc\u0142aw University of Environmental and Life Sciences, Che\u0142mo\u0144skiego 37, 51-630 Wroclaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4140-4824","authenticated-orcid":false,"given":"Marzena","family":"Je\u017cewska-Zychowicz","sequence":"additional","affiliation":[{"name":"Department of Food Market and Consumer Research, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences (SGGW-WULS), Nowoursynowska 159C, 02-776 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Schweiger, V., Martini, A., Nizzero, M., Bonora, E., Del Balzo, G., Gottin, L., Torroni, L., Polati, L., Zuliani, G., and Secchettin, E. (2024). Prevalence of FMS diagnosis according to ACR 2016 revised criteria in a pain therapy centre in Italy: Observational study. Medicina, 60.","DOI":"10.3390\/medicina60040599"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Filipovic, T., Filipovi\u0107, A., Nikolic, D., Gimigliano, F., Stevanov, J., Hrkovic, M., and Bosanac, I. (2025). Fibromyalgia: Understanding, diagnosis and modern approaches to treatment. J. Clin. Med., 14.","DOI":"10.3390\/jcm14030955"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Jurado-Priego, L.N., Cueto-Ure\u00f1a, C., Ram\u00edrez-Exp\u00f3sito, M.J., and Mart\u00ednez-Martos, J.M. (2024). Fibromyalgia: A review of the pathophysiological mechanisms and multidisciplinary treatment strategies. Biomedicines, 12.","DOI":"10.3390\/biomedicines12071543"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e15428","DOI":"10.1111\/1756-185X.15428","article-title":"Epidemiology of fibromyalgia: East versus West","volume":"27","author":"Soroosh","year":"2024","journal-title":"Int. J. Rheum. Dis."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"138","DOI":"10.5114\/reum.2021.106908","article-title":"Prevalence of fibromyalgia in medical students and its association with lifestyle factors\u2014A cross-sectional study","volume":"59","author":"Patel","year":"2021","journal-title":"Reumatologia"},{"key":"ref_6","first-page":"44","article-title":"Prevalence of fibromyalgia symptoms among Polish rheumatologists","volume":"62","year":"2024","journal-title":"Reumatologia"},{"key":"ref_7","first-page":"957","article-title":"Fibromyalgia: One year in review 2025","volume":"43","author":"Iannuccelli","year":"2025","journal-title":"Clin. Exp. Rheumatol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"413","DOI":"10.5114\/reum.2022.123671","article-title":"Fibromyalgia syndrome: Epidemiology, diagnosis and treatment","volume":"60","author":"Kocyigit","year":"2022","journal-title":"Reumatologia"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1007\/s40122-024-00598-2","article-title":"A personalized Mediterranean diet improves pain and quality of life in patients with fibromyalgia","volume":"13","author":"Casini","year":"2024","journal-title":"Pain Ther."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Kahraman, T., and Ayaz, A. (2025). Dietary phytonutrients in fibromyalgia: Integrating mechanisms, biomarkers, and clinical evidence\u2014A narrative review. Medicina, 61.","DOI":"10.3390\/medicina61122211"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Lee, S. (2026). The potential role of a whole food plant-based diet on fibromyalgia symptoms: A review article. Am. J. Lifestyle Med., 15598276261422156.","DOI":"10.1177\/15598276261422156"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1007\/s40122-021-00266-9","article-title":"The role of nutrient supplementation in the management of chronic pain in fibromyalgia: A narrative review","volume":"10","author":"Haddad","year":"2021","journal-title":"Pain Ther."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Ilari, S., Nucera, S., Malafoglia, V., Proietti, S., Passacatini, L.C., Caminiti, R., Mazza, V., Bonaddio, A., Oppedisano, F., and Maiuolo, J. (2025). Does vitamin D supplementation impact fibromyalgia-related pain? A systematic review and meta-analysis. Nutrients, 17.","DOI":"10.3390\/nu17203232"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1007\/s40122-024-00641-2","article-title":"Neuronutritional approach to fibromyalgia management: A narrative review","volume":"13","author":"Badaeva","year":"2024","journal-title":"Pain Ther."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1080\/19390211.2025.2483269","article-title":"Effects of coenzyme Q10, tryptophan, and magnesium supplementation on fatigue in patients with fibromyalgia: A randomized trial","volume":"22","year":"2025","journal-title":"J. Diet. Suppl."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Fern\u00e1ndez-Araque, A., Verde, Z., Torres-Ortega, C., Sainz-Gil, M., Velasco-Gonzalez, V., Gonz\u00e1lez-Bernal, J.J., and Mielgo-Ayuso, J. (2022). Effects of antioxidants on pain perception in patients with fibromyalgia: A systematic review. J. Clin. Med., 11.","DOI":"10.3390\/jcm11092462"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"532","DOI":"10.1177\/1074248418784292","article-title":"Quality of life and its association with treatment satisfaction, adherence to medication, and trust in physician among patients with hypertension: A cross-sectional designed study","volume":"23","author":"Jneid","year":"2018","journal-title":"J. Cardiovasc. Pharmacol. Ther."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"301","DOI":"10.2147\/PPA.S158443","article-title":"Skepticism and pharmacophobia toward medication may negatively impact adherence to psychiatric medications: A comparison among outpatient samples recruited in Spain, Argentina, and Venezuela","volume":"12","author":"Motuca","year":"2018","journal-title":"Patient Prefer. Adherence"},{"key":"ref_19","first-page":"4","article-title":"The role of treatment perceptions in intervention evaluation: A review","volume":"3","author":"Sidani","year":"2020","journal-title":"Sci. Nurs. Health Pract."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Laferton, J.A.C., Vijapura, S., Baer, L., Clain, A.J., Cooper, A., Papakostas, G., Price, L.H., Carpenter, L.L., Tyrka, A.R., and Fava, M. (2018). Mechanisms of perceived treatment assignment and subsequent expectancy effects in a double-blind placebo-controlled RCT of major depression. Front. Psychiatry, 9.","DOI":"10.3389\/fpsyt.2018.00424"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"e13029","DOI":"10.2196\/13029","article-title":"Perceived treatment satisfaction and effectiveness facilitators among patients with chronic health conditions: A self-reported survey","volume":"9","author":"Robertson","year":"2020","journal-title":"Interact. J. Med. Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"30671","DOI":"10.1038\/srep30671","article-title":"Changes in perception of treatment efficacy are associated to the magnitude of the nocebo effect and to personality traits","volume":"6","author":"Corsi","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/j.jpsychores.2004.08.011","article-title":"Reconsidering the role of personality in placebo effects: Dispositional optimism, situational expectations, and the placebo response","volume":"58","author":"Geers","year":"2005","journal-title":"J. Psychosom. Res."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"430","DOI":"10.1016\/j.pain.2010.08.007","article-title":"How the number of learning trials affects placebo and nocebo responses","volume":"151","author":"Colloca","year":"2010","journal-title":"Pain"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2063","DOI":"10.1001\/jama.2017.4545","article-title":"Changing mindsets to enhance treatment effectiveness","volume":"317","author":"Crum","year":"2017","journal-title":"JAMA"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3042","DOI":"10.1093\/rheumatology\/keaa061","article-title":"Diagnosis of fibromyalgia: Comparison of the 2011\/2016 ACR and AAPT criteria and validation of the modified Fibromyalgia Assessment Status","volume":"59","author":"Salaffi","year":"2020","journal-title":"Rheumatology"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"R120","DOI":"10.1186\/ar2783","article-title":"The revised Fibromyalgia Impact Questionnaire (FIQR): Validation and psychometric properties","volume":"11","author":"Bennett","year":"2009","journal-title":"Arthritis Res. Ther."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"\u0106wirlej-Soza\u0144ska, A., Soza\u0144ski, B., \u0141yko, A., \u0141agowska, A., Leszczy\u0144ska, N., Kuduk, B., Wi\u015bniowska-Szurlej, A., and Wilmowska-Pietruszy\u0144ska, A. (2023). Psychometric properties and validation of the Polish version of the Fibromyalgia Impact Questionnaire (FIQ-Pol). BMC Public Health, 23.","DOI":"10.1186\/s12889-023-16411-2"},{"key":"ref_29","first-page":"240","article-title":"Psychometric properties of the revised Fibromyalgia Impact Questionnaire (FIQR): A contribution to the Portuguese validation of the scale","volume":"41","author":"Costa","year":"2016","journal-title":"Acta Reumatol. Port."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"The WHOQOL Group (1998). Development of the World Health Organization WHOQOL-BREF quality of life assessment. Psychol. Med., 28, 551\u2013558.","DOI":"10.1017\/S0033291798006667"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1111\/j.1471-6712.2006.00401.x","article-title":"Quality of life in Polish respondents: Psychometric properties of the Polish WHOQOL-Bref","volume":"20","author":"Jaracz","year":"2006","journal-title":"Scand. J. Caring Sci."},{"key":"ref_32","unstructured":"Gaw\u0119cki, J. (2020). KomPAN\u00ae kwestionariusz do badania pogl\u0105d\u00f3w i zwyczaj\u00f3w \u017cywieniowych dla os\u00f3b w wieku 16\u201365 lat, wersja 1.2\u2014Kwestionariusz do samodzielnego wype\u0142nienia przez respondenta. KomPAN\u00ae Kwestionariusz do Badania Pogl\u0105d\u00f3w i Zwyczaj\u00f3w \u017bywieniowych oraz Procedura Opracowania Danych, Wydawnictwo Komitetu Nauki o \u017bywieniu Cz\u0142owieka Polskiej Akademii Nauk."},{"key":"ref_33","unstructured":"Gaw\u0119cki, J. (2020). The manual for developing nutritional data from the KomPAN\u00ae questionnaire. KomPAN\u00ae Dietary Habits and Nutrition Beliefs Questionnaire and the Manual for Developing Nutritional Data, The Committee of Human Nutrition, Polish Academy of Sciences."},{"key":"ref_34","unstructured":"Ross, A.C., Taylor, C.L., Yaktine, A.L., and Del Valle, H.B. (2011). Dietary Reference Intakes for Calcium and Vitamin D, National Academies Press."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Tollosa, D.N., Van Camp, J., Huybrechts, I., Huybregts, L., Van Loco, J., De Smet, S., Sterck, E., Rab\u00e2i, C., Van Hecke, T., and Vanhaecke, L. (2017). Validity and reproducibility of a food frequency questionnaire for dietary factors related to colorectal cancer. Nutrients, 9.","DOI":"10.3390\/nu9111257"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Zheng, M., Campbell, K.J., Scanlan, E., McNaughton, S.A., and Moran, J.M. (2020). Development and evaluation of a food frequency questionnaire for use among young children. PLoS ONE, 15.","DOI":"10.1371\/journal.pone.0230669"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Ajabnoor, S.M., Jambi, H., and Bahijri, S. (2024). Development and validation of a food frequency questionnaire in adult Saudi subjects in Jeddah city. BMC Public Health, 24.","DOI":"10.1186\/s12889-023-17511-9"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Rusi\u0144ska, A., P\u0142udowski, P., Walczak, M., Borszewska-Kornacka, M.K., Bossowski, A., Chlebna-Sok\u00f3\u0142, D., Czech-Kowalska, J., Dobrza\u0144ska, A., Franek, E., and Helwich, E. (2018). Vitamin D supplementation guidelines for general population and groups at risk of vitamin D deficiency in Poland: Recommendations of the Polish Society of Pediatric Endocrinology and Diabetes and the Expert Panel with participation of national specialist consultants and representatives of scientific societies\u20142018 update. Front. Endocrinol., 9.","DOI":"10.3389\/fendo.2018.00246"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"P\u0142udowski, P., Kos-Kud\u0142a, B., Walczak, M., Fal, A., Zozuli\u0144ska-Zi\u00f3\u0142kiewicz, D., Sieroszewski, P., Peregud-Pogorzelski, J., Lauterbach, R., Targowski, T., and Lewi\u0144ski, A. (2023). Guidelines for preventing and treating vitamin D deficiency: A 2023 update in Poland. Nutrients, 15.","DOI":"10.3390\/nu15030695"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1907","DOI":"10.1210\/clinem\/dgae290","article-title":"Vitamin D for the prevention of disease: An Endocrine Society clinical practice guideline","volume":"109","author":"Demay","year":"2024","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"2318","DOI":"10.3899\/jrheum.090367","article-title":"Fibromyalgia syndrome module at OMERACT 9: Domain construct","volume":"36","author":"Mease","year":"2009","journal-title":"J. Rheumatol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1521","DOI":"10.1007\/s11136-022-03261-5","article-title":"Are OMERACT recommendations followed in clinical trials on fibromyalgia? A systematic review of patient-reported outcomes and their measures","volume":"32","author":"Kock","year":"2023","journal-title":"Qual. Life Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"152423","DOI":"10.1016\/j.semarthrit.2024.152423","article-title":"Defining domains: Developing consensus-based definitions for foundational domains in OMERACT core outcome sets","volume":"66","author":"Maxwell","year":"2024","journal-title":"Semin. Arthritis Rheum."},{"key":"ref_44","unstructured":"World Health Organization (2000). Obesity: Preventing and Managing the Global Epidemic. Report of a WHO Consultation, World Health Organization."},{"key":"ref_45","unstructured":"Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences, Lawrence Erlbaum Associates. [2nd ed.]."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1149","DOI":"10.3758\/BRM.41.4.1149","article-title":"Statistical power analyses using G*Power 3.1: Tests for correlation and regression analyses","volume":"41","author":"Faul","year":"2009","journal-title":"Behav. Res. Methods"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"H\u00e4user, W., Jung, E., Erbsl\u00f6h-M\u00f6ller, B., Gesmann, M., K\u00fchn-Becker, H., Petermann, F., Langhorst, J., Thoma, R., Weiss, T., and Wolfe, F. (2012). The German fibromyalgia consumer reports\u2014A cross-sectional survey. BMC Musculoskelet. Disord., 13.","DOI":"10.1186\/1471-2474-13-74"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"2385","DOI":"10.1093\/rheumatology\/keae707","article-title":"Effectiveness of pharmacological therapies for fibromyalgia syndrome in adults: An overview of Cochrane Reviews","volume":"64","author":"Moore","year":"2025","journal-title":"Rheumatology"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.pain.2010.02.043","article-title":"Contributions of change in clinical status parameters to Patient Global Impression of Change (PGIC) scores among persons with fibromyalgia treated with milnacipran","volume":"149","author":"Geisser","year":"2010","journal-title":"Pain"},{"key":"ref_50","first-page":"352","article-title":"Psychological factors and health-related quality of life in fibromyalgia patients","volume":"12","author":"Campos","year":"2024","journal-title":"Health Psychol. Rep."},{"key":"ref_51","first-page":"3","article-title":"Dietary quality is associated with better self-efficacy and depression in patients with fibromyalgia from a comparative effectiveness trial: A small pilot study","volume":"2","author":"Beauchesne","year":"2020","journal-title":"J. Maine Med. Cent."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Fern\u00e1ndez-Feij\u00f3o, F., Samart\u00edn-Veiga, N., and Carrillo-de-la-Pe\u00f1a, M.T. (2022). Quality of life in patients with fibromyalgia: Contributions of disease symptoms, lifestyle and multi-medication. Front. Psychol., 13.","DOI":"10.3389\/fpsyg.2022.924405"},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Proietti, E., Rapallo, F., Molinari, E., Mucci, V., Marinelli, L., Borgarelli, C., Burlando, B., Pisciotta, L., and Demori, I. (2024). Online questionnaire with fibromyalgia patients shows negative correlations between disease severity and adherence to Mediterranean diet. Nutrients, 16.","DOI":"10.3390\/nu16071078"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1007\/s00296-025-05895-3","article-title":"Development of a fibromyalgia-specific quality of life instrument: The Fibromyalgia Quality of Life Scale (FM-QoLS)","volume":"45","author":"Yilmaz","year":"2025","journal-title":"Rheumatol. Int."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1417","DOI":"10.1007\/s00296-010-1443-0","article-title":"Fibromyalgia and nutrition, what do we know?","volume":"30","author":"Arranz","year":"2010","journal-title":"Rheumatol. Int."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"406","DOI":"10.1016\/j.jand.2014.10.023","article-title":"Vitamin D supplementation and health-related quality of life: A systematic review of the literature","volume":"115","author":"Hoffmann","year":"2015","journal-title":"J. Acad. Nutr. Diet."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1443","DOI":"10.1001\/jama.2020.26498","article-title":"Screening for vitamin D deficiency in adults: Updated evidence report and systematic review for the US Preventive Services Task Force","volume":"325","author":"Kahwati","year":"2021","journal-title":"JAMA"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1038\/s41574-021-00593-z","article-title":"The health effects of vitamin D supplementation: Evidence from human studies","volume":"18","author":"Bouillon","year":"2022","journal-title":"Nat. Rev. Endocrinol."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"1111","DOI":"10.1007\/s11845-023-03521-4","article-title":"The effect of vitamin D treatment on quality of life in patients with fibromyalgia","volume":"193","author":"Ersoy","year":"2024","journal-title":"Ir. J. Med. Sci."},{"key":"ref_60","doi-asserted-by":"crossref","unstructured":"Lombardo, M., Feraco, A., Ottaviani, M., Rizzo, G., Camajani, E., Caprio, M., and Armani, A. (2022). The efficacy of vitamin D supplementation in the treatment of fibromyalgia syndrome and chronic musculoskeletal pain. Nutrients, 14.","DOI":"10.3390\/nu14153010"},{"key":"ref_61","first-page":"e20250031","article-title":"Fibromyalgia patients\u2019 perceptions of diagnosis, life and the psychological impact of the disease","volume":"8","author":"Oliveira","year":"2025","journal-title":"BrJP"},{"key":"ref_62","first-page":"970","article-title":"Mediterranean diet and its low-antigenic and anti-inflammatory properties on fibromyalgia: A systematic review","volume":"43","author":"Miller","year":"2025","journal-title":"Clin. Exp. Rheumatol."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1038\/sj.ebd.6400375","article-title":"Study design III: Cross-sectional studies","volume":"7","author":"Levin","year":"2006","journal-title":"Evid. Based Dent."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"261","DOI":"10.4103\/0019-5154.182410","article-title":"Methodology series module 3: Cross-sectional studies","volume":"61","author":"Setia","year":"2016","journal-title":"Indian J. Dermatol."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1111\/j.1751-5823.2010.00112.x","article-title":"Selection bias in web surveys","volume":"78","author":"Bethlehem","year":"2010","journal-title":"Int. Stat. Rev."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1007\/s00127-009-0171-9","article-title":"Advantages and limitations of web-based surveys: Evidence from a child mental health survey","volume":"46","author":"Heiervang","year":"2011","journal-title":"Soc. Psychiatry Psychiatr. Epidemiol."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1097\/JOM.0b013e3181a86671","article-title":"How accurate are self-reports? Analysis of self-reported health care utilization and absence when compared with administrative data","volume":"51","author":"Short","year":"2009","journal-title":"J. Occup. Environ. Med."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"211","DOI":"10.2147\/JMDH.S104807","article-title":"Information bias in health research: Definition, pitfalls, and adjustment methods","volume":"9","author":"Althubaiti","year":"2016","journal-title":"J. Multidiscip. Healthc."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/j.jpain.2010.01.002","article-title":"Comparative Efficacy and Harms of Duloxetine, Milnacipran, and Pregabalin in Fibromyalgia Syndrome","volume":"11","author":"Petzke","year":"2010","journal-title":"J. Pain"},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"640","DOI":"10.1016\/j.mayocp.2016.02.002","article-title":"Opioid Use in Fibromyalgia: A Cautionary Tale","volume":"91","author":"Goldenberg","year":"2016","journal-title":"Mayo Clin. Proc."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1136\/annrheumdis-2016-209724","article-title":"EULAR Revised Recommendations for the Management of Fibromyalgia","volume":"76","author":"Macfarlane","year":"2017","journal-title":"Ann. Rheum. Dis."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/15\/5956\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T04:30:47Z","timestamp":1785558647000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/15\/5956"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,30]]},"references-count":71,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["jcm15155956"],"URL":"https:\/\/doi.org\/10.3390\/jcm15155956","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,30]]}}}