Table 4.

False Positive Rates for Unbalanced Trials Over a Simulation of 2 Years

	Year 1		Year 2
Sample Size	Total N(%) of FP	N(%) of FP by SNP Effect	Total N(%) of FP	N(%) of FP by SNP Effect
50	61 (6.1%)	30 (49.2%)	56 (5.6%)	40 (71.4%)
100	58 (5.8%)	48 (82.8%)	52 (5.2%)	44 (84.6%)
200	59 (5.9%)	43 (72.9%)	57 (5.7%)	49 (86.0%)
300	45 (4.5%)	32 (71.1%)	57 (5.7%)	47 (86.0%)
600	45 (4.5%)	32 (71.1%)	57 (5.7%)	43 (75.4%)
700	60 (6.0%)	47 (78.3%)	48 (4.8%)	44 (91.7%)
800	57 (5.7%)	43 (75.4%)	43 (4.3%)	32 (74.4%)

FP = false positive. False positive rates were investigated by determining the number of significant and non-significant trials when comparing change in UPDRS over a simulation of two years. Total % of false positives is the percentage of total iterations that resulted in a false positive. % of false positives by SNP effect is the percentage of false positives that were caused by the interaction effect on UPDRS progression by the rs9298897 and rs17710829 SNPs alone. Significance was determined by Z score cut-off values of ± 1.96 (p < 0.05).