S0007 [Source: Ng et al. (2005). CHEST 128:1315-1323.]
A cross-sectional telephone survey was conducted on 3,047 6-12 year-old apparently healthy children.
In the cohort of primary school children, habitual snoring was found in 333 subjects (10.9%, 95% confidence interval [CI] was 10 to 12%). The male/female ratio of habitual snorers was 2.4:1.
Witnessed sleep apnea was found in 45 children (1.5%; 95% CI was 1 to 2%).
Q1. How do you interpret the 95% confidence interval for the proportion of Hong Kong primary school children who had habitual snoring?
Q2. What statistical test may be used to examine if habitual snoring occurred more in male children than female children?
Q3. Why do we need to perform a test and you may have suggested in Q2 but not merely make conclusion based on the 2.4:1 ratio?
Q4. What is the maximum error (up to 95% confidence) of using 10.9% in estimating the proportion of primary school children with habitual snoring?
Q5. The error incurred in the estimation of the proportion of primary school children with sleep apnea appears to be smaller than that with habitual snoring. Discuss why.