Table III.
Zero-effect tests.
| Testa | Null vs. alternative | Measure | Df | χ2 | Prob level |
|---|---|---|---|---|---|
| Non-directional | H0: all treatment effects are zero | ln (RR) | 9 | 20.06 | 0.017546 |
| Ha: at least one is not zero | |||||
| Directional | H0: all treatment effects are zero | ln (RR) | 1 | 6.86 | 0.008815 |
| Ha: effects are equal to the same non-zero quantity |
a
Manual calculation of test statistics based on ln (RR) and SE ln (RR) output from Comprehensive Meta-Analysis, version 2.0. Both tests show significance at the 5% significance level, so the null hypothesis may be rejected. Df, degree of freedom; RR, risk ratio; SE, standard error.