THE Q-TIP TEST AND URETHROVESICAL JUNCTION MOBILITY

Objective: To determine the accuracy of the Q-tip test to measure uret hrovesical junction mobility. Methods: One hundred fourteen women with urinary incontinence or genital prolapse were evaluated with a Q-tip test and perineal ultrasound scanning to measure urethrovesical juncti on mobility with strain. The sensitivity, specificity, and positive an d negative predictive values of the Q-tip test to diagnose urethrovesi cal junction hypermobility were calculated using ultrasound as the sta ndard. Repeat Q-tip and ultrasound measurements were obtained in ten s ubjects and analyzed for reproducibility. Results: The Q-tip test had a sensitivity of 25%, specificity of 78%, positive predictive value of 67%, and negative predictive value of 37%. The Q-tip and ultrasound m easurements were reproducible, as the within-subject variation was sig nificantly small when compared to between-subject variation (P = .0001 ). Conclusion: The Q-tip test is inaccurate for measurement of urethro vesical junction mobility and should not be used in the manner describ ed to diagnose urethrovesical junction hypermobility.