Comparing three fibromyalgia screening tools: diagnostic accuracy and clinical utility

Objectives: Brief self-administered screening tools have been developed to facilitate rapid recognition of fibromyalgia (FM) features. This study evaluated the diagnostic performance of three commonly used screening tools. Methods: In this cross-sectional study, consecutive female patients with chronic multisite pain completed three FM screening tools, respectively the Fibromyalgia Rapid Screening Tool (FiRST), the Nociplastic-Based Fibromyalgia Features (NFF) tool, and the Self-Administered Fibromyalgia Screening (SIFIS) questionnaire. Patients were dichotomised in FM (2016 ACR criteria) and non-FM controls, including patients with common non-inflammatory musculoskeletal pain conditions. Discriminative ability was evaluated using the Area Under the Receiver Operating Characteristic Curve (AUC-ROC) analysis and Decision Curve Analysis (DCA) quantified net clinical benefit across probability thresholds. Results: Among 205 patients, 106 (51.7%) met criteria for FM. SIFIS demonstrated the highest discriminative performance (AUC=0.941) with sensitivity 82.1%, specificity 91.8%, and accuracy 86.8% at a cut-off ≥4. FiRST (cut-off ≥5) achieved AUC=0.827, sensitivity 75.5%, specificity 69.4%, accuracy 77.0%. NFF (cut-off ≥4) achieved AUC=0.829, sensitivity 80.2%, specificity 69.4%, accuracy 75.0%. Differences between SIFIS and the other tools were statistically significant (p<0.001). DCA showed that SIFIS provided the highest net clinical benefit across a broad range of thresholds. Conclusions: In patients with chronic multisite musculoskeletal pain, SIFIS exhibits superior diagnostic accuracy and clinical utility compared with FiRST and NFF. Integration of ROC and DCA demonstrates that SIFIS not only discriminates FM effectively but also offers meaningful clinical benefit, supporting its role as a practical screening tool in routine clinical practice.