Claim: A polysomnography AHI rating of <5 is considered normal, 5-15 is mild and 15-30 is moderate, while anything over 30 is severe.
Evidence: Normal: AHI<5 Mild sleep apnea: 5≤AHI<15 Moderate sleep apnea: 15≤AHI<30 Severe sleep apnea: AHI≥30 The Apnea–Hypopnea Index or Apnoea–Hypopnoea Index (AHI) is an index used to indicate the severity of sleep apnea. Polysomnography (PSG), a type of sleep study, is a multi-parametric test used in the study of sleep and as a diagnostic tool in sleep medicine.