The PhenX Toolkit is designed primarily for investigators who wish to expand their disease-specific studies into other areas and who are unlikely to have sufficient resources to add more than a few measures from additional research domains that are outside their primary focus. The Toolkit provides a variety of measures; it is up to investigators to decide which PhenX measures (and how many) they want to incorporate into their overall study design. The overall process of selecting PhenX measures is outlined in Figure 1.
