STUDY OBJECTIVE: The aim of this study is to evaluate whether adding the item of 
"apple body type" to the STOP-BANG questionnaire enhances diagnostic performance 
of the questionnaire for detecting obstructive sleep apnea (OSA).
DESIGN: Cross-sectional study.
SETTING: Sleep center setting.
PATIENTS: Two hundred and eight subjects who were referred for an evaluation of 
possible OSA at Tulane Comprehensive Sleep Center. The exclusion criteria were 
age<18years old, incomplete or absent questionnaire, incomplete body type 
identification, polysomnography (PSG) refusal, and pregnant women.
INTERVENTIONS: STOP-BANG items and body type data were collected on the initial 
clinic visit. An overnight PSG was performed on every participant.
MEASUREMENTS: Descriptive analyses of the demographic data and PSG variables 
were performed. The predictive parameters of STOP and STOP-BANG without and with 
body type score (STOP-Apple and STOPBANG-Apple) were compared.
MAIN RESULTS: The STOP questionnaire's sensitivity/specificity/positive 
likelihood ratio (+LR) (cut-off=2) was 96%/11%/1.1, respectively whereas the 
STOP-Apple questionnaire (cut-off=3) was 88%/39%/1.5. The STOP-BANG's 
sensitivity/specificity/+LR (cut-off=3) was 96%/19%/1.2, respectively whereas 
the STOP-BANG-Apple questionnaire (cut-off=4) was 90%/39%/1.5. The area under 
the Receiver Operating Characteristic (ROC) curve of STOP-Apple was comparable 
to the STOP-BANG (P=0.25). The addition of the apple body type item to the 
STOP-BANG questionnaire in participants with a score≥3 led to increased 
specificity (67.4%), increased the odds ratio of having OSA of 2.5 (95% CI, 
1.2-5.3) and odds ratio of having moderate-severe OSA of 4.7 (95% CI, 2.5-8.7).
CONCLUSION: In the sleep center setting, adding the body type item to the 
STOP-BANG questionnaire improves not only clinical prediction for PSG confirmed 
OSA but also predicts moderate to severe of OSA.