Table 3:
Example TB diagnostic trial analysed with each GEE method.
|
Working correlation matrix |
||
|---|---|---|
| Independent | Exchangeable | |
| Odds ratio estimate | 1.65 | 1.51 |
| Standard error (percentage increase compared to uncorrected standard error)a | ||
| Uncorrected | 0.1684 | 0.1115 |
| FG | 0.2056 (+22%) | 0.1196 (+7%) |
| KC | 0.1891 (+12%) | 0.1948 (+75%) |
| MD | 0.2198 (+30%) | 0.1395 (+25%) |
| MBN | 0.1956 (+16%) | 0.1422 (+28%) |
| MW | 0.2818 (+67%) | 0.1865 (+67%) |
| KC approximation | 0.1921 (+14%) | 0.1245 (+12%) |
| Degrees of Freedom | ||
| Pan and Wallb | 70.1 | 17.9 |
| Fay and Graubardb | 7.6 | 10.5 |
| Clusters minus parameters | 5 | 5 |
| Cluster periods minus parameters | 103 | 103 |
| Cluster periods minus parameters with clusters regarded as parameters | 89 | 89 |
| (95% CI) p-value | ||
| Uncorrected | (1.19, 2.30) p = 0.003 | (1.22, 1.88) p < 0.001 |
| FG + DFFG | (1.02, 2.66) p = 0.04 | (1.16, 1.97) p = 0.006 |
| FG + DFC-P | (0.97, 2.80) p = 0.06 | (1.11, 2.06) p = 0.02 |
| KC approx. + DFFG | (1.06, 2.58) p = 0.03 | (1.15, 1.99) p = 0.007 |
| KC approx. + DFC-P | (1.01, 2.71) p = 0.05 | (1.10, 2.08) p = 0.02 |
FG: Fay and Graubard; KC: Kauermann and Carroll; MD: Mancl and DeRouen; MBN: Morel, Bokossa, and Neerchal; MW: Mackinnon and White; GEE: Generalised estimating equations.
aStandard errors given on the log odds ratio scale.
bUsing Fay and Graubard standard error.