Systems and methods for using blood pressure monitoring instrument inaccuracy to accomplish categorization based on the instrument's measurements and inaccuracy in conjunction with a categorization assessment algorithm are disclosed. Incorporation of inaccuracy enables high confidence screening for cardiovascular risk based on biomarker and other data within risk criteria algorithms, and also incorporating blood pressure monitoring instrument measurement with inaccuracy. Screening results can be displayed as a confidence figure above or below a risk threshold, or via assignment into one of various risk categories around a threshold, with the categories determined in part by apparatus inaccuracy.
