ABSTRACT
STUDY OBJECTIVES: This pilot study explored the sensitivity and specificity of a brief survey to determine the presence of cataplexy. We hypothesized that the brief questionnaire could provide a quick, sensitive, and specific screening tool to identify those patients with cataplexy, which would result in more timely referrals for further diagnostic testing. DESIGN: The pilot study utilized a brief questionnaire that was developed by including 5 questions that were found to be strong positive predictors of cataplexy from a previous 51-item cataplexy questionnaire. SETTING: Participants with a laboratory-confirmed diagnosis completed the questionnaire via mail correspondence or at the time of scheduled appointments in the Mayo Clinic Sleep Disorder Center, Rochester, Minn. PARTICIPANTS: Seventy-eight patients with narcolepsy and cataplexy and 78 patients with obstructive sleep apnea completed the questionnaire. INTERVENTIONS: NA. MEASUREMENTS AND RESULTS: The sensitivity, specificity, area under the curve, positive predictive value, and negative predictive value/were computed for each question individually, along with appropriate 95% confidence intervals. CONCLUSIONS: The first item of the cataplexy emotional trigger questionnaire (CETQ) discriminates patients with cataplexy from controls with excellent sensitivity and specificity. The addition of the other 4 questions, in the context of question 1, did not improve specificity, area under the curve, positive predictive value, or negative predictive value but did provide useful confirmatory data. Thus, a single question provides a brief practical tool that could improve the recognition of cataplexy in the clinical setting. Depending on the circumstance, users may be interested in utilizing 1 or all 5 questions.
