Accuracy of the diagnosis of fibromyalgia by family physicians: is the pendulum shifting?

OBJECTIVE

We evaluated the accuracy of diagnosis of fibromyalgia (FM) by family physicians.

METHODS

We performed a retrospective cohort analysis of 646 consecutive patients newly referred to the outpatient rheumatology clinic of Soroka University Medical Center from January 1, 2005, until December 31, 2007. The kappa statistic was used to measure agreement between family-physician and rheumatologist diagnoses for FM in the total patient cohort as well as in groups stratified by ethnicity. Sensitivity and specificity of family-physician diagnosis of FM were calculated using rheumatologist diagnosis as the gold standard. There were no exclusion criteria.

RESULTS

During the time period of the study, 646 new patients were seen in the rheumatology clinic. Of 196 patients referred with an initial diagnosis of FM, the consultant rheumatologist confirmed this diagnosis in 71% of cases. The overall kappa for FM diagnosis between family physicians and rheumatologists was 0.70 (p<0.001), indicating a good level of agreement. Agreement was substantially lower among Bedouin patients (kappa=0.35, p=0.003). All other patients in our study were Jewish Israelis. Using rheumatologist diagnosis as the gold standard, overall sensitivity and specificity of FM diagnosis by family physicians were 87.4% and 88.3%, respectively.

CONCLUSION

Family physicians in our region are able to accurately diagnose FM. Future studies might focus on evaluating the factors and biases accounting for differences in level of diagnostic accuracy for FM among various ethnic groups.