Fuzzy FMEA Application for Variables in Factor Analysis to Prioritize Suspected OSA Patients for Sleep Study

The investigations for diagnosis and severity of OSA in Thai population need RDI from the PSG in sleep laboratory. The current problems of Thailand are firstly, inadequate sleep specialist and experienced technician: secondly, inadequate sleep laboratory result in long queue of appointments for sleep study. The authors proposed the new application for solving problem and developing to prioritize risk of OSA. The population data had 19 failures for suspected OSA patients in sleep clinic and RDI in PSG study from sleep laboratory center of Siriraj Hospital (2010-2011). The statistical tool used, was Fuzzy logic algorithm consisted of Fuzzy approach FMEA, linguistic variables, 360 Fuzzy IF–then rule bases and Mamdani Max-Min composition. The purpose of this research was to present specialist consensus based Fuzzy FMEA application for 19 failures to prioritize the risk of OSA for appointment with FRPN. The results showed that the indications of special appointment were groups of symptoms respectively as followed: 1.witnessed snoring and apnea; 2. witnessed snoring and apnea*; 3.symptoms at night awakening; 4.Epworth sleepiness scale (3/8, 6/8, 7/8); 5.underlying diseases and personal variables; 6.body built; 7. symptoms during sleep; 8.choking and witnessed snoring, risk variables and work, decreased mental and physical performances; 9.lung disease and sleep-wake pattern and sleep maintenance; 10.related personal variables. The regular appointment should include 11.Epworth sleepiness scale (2/8) and related variables; 12. causes of night awakening; and underlying disease and sleeping posture; 13.underlying diseases and surreal dream. It is suggested that Fuzzy FMEA application is quite practical to be used to queue the suspected OSA patient for sleep study and treatment. Keyword: FMEA, Fuzzy logic, Fuzzy IF–then rule base and Mamdani Max-Min composition, RDI, PSG, OSA