Objective: To analyze whether the Mallampati score is reliable as a simple diagnostic test for predicting obstructive sleep apnea syndrome (OSAS).
Data sources: A literature search was performed using PubMed, Embase, Scopus, Cochrane, and CINAHL databases.
Review methods: Studies were ranked by their relevance and validity in a critical appraisal table. Positive and negative predictive values were obtained or recalculated from the selected articles.
Results: Eight relevant articles met the inclusion criteria. Three studies reported predictive values for a Mallampati score of 3 to 4. The prevalence (or prior probability) of OSAS in these 3 studies was 58% (95% confidence interval [CI], 50-67), 76% (95% CI, 72-79), and 82% (95% CI, 80-84), respectively. With a Mallampati score of 1 to 2, the risk of OSAS decreases to 45% (95% CI, 33-58), 74% (95% CI, 70-78), and 81% (95% CI, 77-86), respectively. With a Mallampati score of 3 to 4, the risk of OSAS is 69% (95% CI, 59-80), 82% (95% CI, 74-89), and 82% (95% CI, 79-85), respectively. The differences between the prior and the posterior probabilities are rather small and do not reach statistical significance.
Conclusion: There is no evidence to maintain that the Mallampati score is of added value for ruling in or ruling out a diagnosis of OSAS in patients suspected for OSAS.