FP rates for unbalanced trials over a simulation of 2 years
| Sample size | Year 1 | Year 2 | ||
| 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 rates were investigated by determining the number of significant and non-significant trials when comparing change in UPDRS over a simulation of 2 years. Total % of FPs is the percentage of total iterations that resulted in an FP. % of FPs by SNP effect is the percentage of FPs 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).
FP, false positive; UPDRS, Unified Parkinson’s Disease Rating Scale.