Validity and reliability of fibromiyalgia 2013 alternative diagnostic criteria

Purpose: In this study, we aimed to test the ACR 2011 modified and 2013 alternative diagnostic criteria in patients with 3-month-long widespread pain. Thus, the sensitivity and specificity of these criteria with respect to FM will be compared and their value in relation to secondary fibromyalgia will be investigated. Materials and methods: A total of 280 female patients who were admitted due to chronic pain of 3 months long were included in the study. According to these criteria, the demographic characteristics of the selected patients, their additional diseases and the drugs they used were recorded by questioning. A detailed history was taken from all patients and detailed physical examinations were performed. The patients were divided into two groups, non-inflammatory and inflammatory groups. All the patients were evaluated using ACR 1990, ACR 2011 modified criteria and 2013 alternative diagnostic criteria. Behavioral Beck depression scale and fibromyalgia effect questionnaire were administered. Results: In non-inflammatory group, 122 (87.2%) patients were diagnosed as FM according to ACR 2011 modified diagnostic criteria. According to the alternative criteria, 97 (69.3%) patients were diagnosed as FM. According to ACR 2011 modified diagnostic criteria, the number of patients with FM diagnosis but not diagnosed according to 2013 alternative criteria was 26 (18.6%). Only 1 (0.7%) patient was diagnosed as FM according to 2013 alternative criteria, but no diagnosis was made according to ACR 2011 modified diagnostic criteria. The kappa value was 0.459, indicating incompatibility (p <0.001). In inflammatory group, 116 (82.9%) patients were diagnosed as FM according to the ACR 2011 modified diagnostic criteria. According to 2013 alternative criteria, 86 (61.4%) patients were diagnosed as FM. According to both criteria, the number of FM patients was 84 (60.0%). According to ACR 2011 modified diagnosis criteria, the number of patients with FM diagnosis but not diagnosed according to 2013 alternative criteria was 24 (17.1%). Only 2 (1.4%) patients were diagnosed with FM according to 2013 alternative criteria but were not diagnosed according to ACR 2011 modified diagnostic criteria. The kappa value was 0.428, indicating incompatibility (p <0.001). Conclusion: Patients with chronic widespread pain are more likely to be diagnosed with FM with the ACR 2011 modified criteria. In addition, in the 2011 criteria 'no other disease that can explain pain' makes it impossible to determine the FM accompanying rheumatic diseases. For this reason, it may be more appropriate to use the 2013 alternative criteria, which set the specificity as 92.9% instead of the 2011 modified criteria. Keywords: Fibromyalgia, ACR 2011 modified criteria, 2013 alternative criteria