[Screening and verification of questionnaire indexes for epidemiological studies on spondyloarthropathy].

Objective: To screen the parameters of questionnaire in prevalence survey of spondyloarthropathy (SpA) in China, and to evaluate the value and feasibility of questionnaire used in prevalence survey.

Methods: A questionnaire study on SpA with 12 questions involved was performed which came from a epidemiological survey on SpA in Brittany, France.

Results: (1) We found difference on the sensitivity and specificity of some indexes in the questionnaires between the French study and the one developed by ourselves. The sensitivity differed between the published French paper and ours in the following indexes: onset age, psoriasis and inflammatory bowel disease. The specificity of the indexes would include spinal pain, insidious onset, morning stiffness, duration more than 3 months and radiographic manifestation also showed differences. (2) Excluding the radiographic abnormality, we ran the logistic regression and concluded that the following parameters were the independent indexes which suggesting the existence of the disease: spinal pain onset before 40 years of age, having spinal stiffness in the morning having positive family history and having buttock pain and heel pain. (3) Based on the result of each question of the questionnaire, indices of distinguishing the cases and controls were identified.

Conclusion: The questionnaire verified in our study was a new, simple, valuable and feasible one for SpA prevalence study and in screening the potential SpA patients.