Table 4 Sample size estimation (statistical power: 80% power, at the 5% significance level).
Condition | Annual rate of medication use per 100 problem-specific encounter | Sample size (no. of GPs required in each arm) |
|---|---|---|
Asthma- use of preventers | 53.2 | 54 |
Asthma- SA Bronchodilators | 53.1 | 54 |
Depression- SSRI | 41.7 | 85 |