A pictorial Sleepiness and Sleep Apnoea Scale to recognize individuals with high risk for obstructive sleep apnea syndrome

PURPOSE: The aim of this study was to evaluate the validity of a new pictorial form of a screening test for obstructive sleep apnea syndrome (OSAS) – the pictorial Sleepiness and Sleep Apnoea Scale (pSSAS). Validation was performed in a sample of patients admitted to sleep clinics in the UK and Switzerland. PATIENTS AND METHODS: All study participants were investigated with objective sleep tests such as full-night-attended polysomnography or polygraphy. The pSSAS was validated by taking into account the individual result of the sleep study, sleep-related questionnaires and objective parameters such as body mass index (BMI) or neck circumference. Different scoring schemes of the pSSAS were evaluated, and an internal validation was undertaken. RESULTS: The full data set consisted of 431 individuals (234 patients from the UK, 197 patients from Switzerland). The pSSAS showed good predictive performance for OSAS with an area under the curve between 0.77 and 0.81 depending on which scoring scheme was used. The subscores of the pSSAS had a moderate-to-strong correlation with widely used screening questionnaires for OSAS or excessive daytime sleepiness as well as with BMI and neck circumference. CONCLUSION: The pSSAS can be used to select patients with a high probability of having OSAS. Due to its simple pictorial design with short questions, it might be suitable for screening in populations with low health literacy and in non-native English or German speakers.