{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T12:11:36Z","timestamp":1790079096404,"version":"4.0.1"},"reference-count":47,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T00:00:00Z","timestamp":1789776000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background: The International Association for the Study of Pain defines pain as a sensory and an emotional experience, yet no instrument in routine practice quantifies affective hypersensitivity to low-intensity interpersonal stimuli, a pattern we term emotional allodynia, a construct transposed from thermal stimuli in major depression, which this study sets out to validate rather than assume. The Emotional Allodynia Questionnaire (AEQ), an 11-item self-report measure, was preliminarily validated in a single-center fibromyalgia sample, showing excellent internal consistency and a unidimensional structure. This protocol describes the multicenter validation phase. Methods: PEARL is a prospective, multicenter, observational case\u2013control study at five Italian tertiary pain centers. Cases are adults with fibromyalgia diagnosed by the 2016 American College of Rheumatology (ACR) criteria; controls are adults with chronic non-cancer pain of defined nociceptive or neuropathic origin. All participants complete the AEQ together with the Central Sensitization Inventory (CSI), Pain Catastrophizing Scale, Beck Depression Inventory-II, State-Trait Anxiety Inventory, Difficulties in Emotion Regulation Scale and a pain visual analog scale, and are reassessed once at 40 \u00b1 10 days. The targets are 274 cases and 151 evaluable controls, sized respectively for the precision of internal consistency within depression strata and for a 95% confidence interval of width 0.10 around an area under the curve of 0.80. Analyses cover internal structure, convergent and discriminant validity, test\u2013retest reliability, AEQ\u2013CSI phenotyping and covariate-adjusted discrimination. Results: Results are not yet available; recruitment began on 10 September 2025 and should be complete by approximately December 2027. Conclusions: The preliminary phase could not say whether the AEQ separates fibromyalgia from other chronic pain, whether the construct holds over time, or whether it survives adjustment for depression, anxiety, catastrophizing and emotion dysregulation. PEARL is designed to test these three questions, and to examine whether the AEQ\u2013CSI phenotypes replicate. Registered on ClinicalTrials.gov (NCT07677631).<\/jats:p>","DOI":"10.3390\/jcm15187299","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T11:09:35Z","timestamp":1790075375000},"page":"7299","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pain, Emotional Allodynia, and Relational Load (PEARL): Protocol of a Multicenter Observational Case\u2013Control Study Validating the Emotional Allodynia Questionnaire in Fibromyalgia"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9760-9394","authenticated-orcid":false,"given":"Alberto","family":"Corriero","sequence":"first","affiliation":[{"name":"Department of Interdisciplinary Medicine, Pain and ICU Section, University of Bari Aldo Moro, Piazza G. Cesare 11, 70124 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4901-0045","authenticated-orcid":false,"given":"Mariateresa","family":"Giglio","sequence":"additional","affiliation":[{"name":"Department of Interdisciplinary Medicine, Pain and ICU Section, University of Bari Aldo Moro, Piazza G. Cesare 11, 70124 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfonso","family":"Pilolla","sequence":"additional","affiliation":[{"name":"Department of Interdisciplinary Medicine, Pain and ICU Section, University of Bari Aldo Moro, Piazza G. Cesare 11, 70124 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7102-9108","authenticated-orcid":false,"given":"Paolo","family":"Trerotoli","sequence":"additional","affiliation":[{"name":"Department of Interdisciplinary Medicine, Statistics Section, University of Bari Aldo Moro, Piazza G. Cesare 11, 70124 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vittorio","family":"Schweiger","sequence":"additional","affiliation":[{"name":"Department of Surgery, Dentistry, Pediatrics and Gynecology, University of Verona, Piazzale L.A. Scuro 10, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5628-184X","authenticated-orcid":false,"given":"Enrico","family":"Polati","sequence":"additional","affiliation":[{"name":"Department of Surgery, Dentistry, Pediatrics and Gynecology, University of Verona, Piazzale L.A. Scuro 10, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Caterina","family":"Pace","sequence":"additional","affiliation":[{"name":"Department of Women, Child and General and Specialized Surgery, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9659-0847","authenticated-orcid":false,"given":"Maria Beatrice","family":"Passavanti","sequence":"additional","affiliation":[{"name":"Department of Women, Child and General and Specialized Surgery, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3059-9865","authenticated-orcid":false,"given":"Gabriele","family":"Finco","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences and Public Health, University of Cagliari, 09042 Cagliari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7664-8928","authenticated-orcid":false,"given":"Salvatore","family":"Sardo","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences and Public Health, University of Cagliari, 09042 Cagliari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9954-4117","authenticated-orcid":false,"given":"Boaz Gedaliahu Samolsky","family":"Dekel","sequence":"additional","affiliation":[{"name":"Anesthesia and Pain Therapy Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, Via Massarenti 9, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9885-9555","authenticated-orcid":false,"given":"Maria Cristina","family":"Sorella","sequence":"additional","affiliation":[{"name":"Anesthesia and Pain Therapy Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, Via Massarenti 9, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cinzia","family":"Di Venosa","sequence":"additional","affiliation":[{"name":"Department of Interdisciplinary Medicine, Pain and ICU Section, University of Bari Aldo Moro, Piazza G. 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