STUDY DESIGN: This prospective diagnostic accuracy study was divided into two phases.

SETTING: The study was conducted at a quaternary teaching hospital.

METHODS: Polysomnograms performed from 1 April 2014 to 31 December 2021 were included. In Phase 1, the parameters of 95 oximetry trend graphs were evaluated, and a modified scoring system was constructed. In Phase 2, the modified scoring system was employed in 272 oximetry trend graphs, and its diagnostic accuracy was determined. A logistic regression model was used to assess the ability of each scoring system to predict paediatric OSAS.

RESULTS: A total of 367 patients were recruited. In Phase 1, a four-tier severity classification system was constructed. In Phase 2, its diagnostic accuracy was found to be 53.3% sensitive, 97% specific, with positive predictive value of 98.5% and negative predictive value of 34.6%. The lowest detectable apnoea-hypopnoea index (AHI) was 4.5. The inter-rater reliability calculated was 80%. Logistic regression was applied to assess associations of the modified McGill score (MMS) or McGill oximetry score (MOS) with OSAS. The area under the receiver operating characteristic curve was higher for the MMS than for MOS (0.78 [95% CI 0.73-0.84] vs. 0.59 [95% CI 0.51-0.66]).

AIMS: To determine the (a) diagnostic accuracy, interobserver reliability and reliable oxygen desaturation index of 4% (ODI4) score at diagnosing obstructive sleep apnoea syndrome in children and (b) correlation between the apnoea hypopnoea index (AHI) with ODI4 and oxygen nadir between both PSG and oximetry.

METHODS: This cross-sectional study included children aged 1-18 years old, undergoing a fully attended overnight PSG for suspected obstructive sleep apnoea syndrome. The Nonin 3150 WristOx2 ™ [Fig. 2] was worn simultaneously during the PSG. Poor oximetry recordings were excluded. Pulse oximetry was scored using the McGill Oximetry Score (MOS) whereby a score of 2-4 was positive for OSAS. Specificity, sensitivity, positive predictive values (PPV), negative predictive values (NPV) and interobserver reliability of the WristOx2 were calculated.

RESULTS: One hundred and sixty-two children with a mean (SD) age of 9.3 (±3.5) years (range 2 years 6 months old - 17 years old) were included after excluding 18 children (poor oximetry data [n = 16] and incomplete PSG [n = 2]). Interobserver agreement of the WristOx2 was 0.8763 (95% CI:0.80, 0.95). WristOx2 had a sensitivity 50%, specificity 96.7%, PPV 96% and NPV 53% at diagnosing OSAS. ODI4 ≥ 2 events/hour in oximetry had a sensitivity of 97.6% and negative predictive value of 85.7% at diagnosing OSA.