Sensitivity, specificity, and positive and negative predictive value (PPV, NPV), for age-related macular degeneration simulation. Predicted risks of age-related macular degeneration are obtained using logistic regression analysis based on six genetic variants entered as categorical variables. The frequency of the population at high-risk is defined as the proportion of individuals with predicted risks equal to or higher than the chosen risk threshold. The genotypic odds ratios and frequencies were obtained from the paper by Seddon et al. . Disease risk is 9%.