Table 3.

Observed powers at different significance levels in simulation studies based on 100,000,000 replicates under the alternative hypothesis, each replicate with 5,000 cases and 5,000 frequency-matched controls with respect to the secondary phenotype.

	Observed powers
Significance	Logistic (without adjustment)	Logistic (with adjustment)	Our approach
1.00E-04	95.12%	95.19%	99.41%
5.00E-05	93.12%	93.24%	99.03%
1.00E-05	86.58%	86.77%	97.60%
5.00E-06	83.10%	83.20%	96.58%
1.00E-06	73.04%	73.48%	93.23%
5.00E-07	68.31%	68.77%	91.23%
1.00E-07	56.50%	57.03%	85.19%
5.00E-08	51.38%	51.91%	82.08%
1.00E-08	39.88%	40.46%	73.42%