The clinical characteristics of this non-existent condition were designed to model descriptions, phenotypes, and diagnostic ambiguities that can be found in actual common, and especially psychiatric, disease classification. The extensive description of KPD was designed to reflect the uncertainty, difficulty, and controversy in defining common disease phenotypes. These phenotypes often include sub-clinical, or endo-, phenotypes that are common in the general population but are thought to be related to the disease; however, the connection to disease is often uncertain. We also simulated such endophenotype information, most of which was genetic and related to the disease. Genetic studies of an actual disease often differ in the choice of phenotypic criteria and family structure used for ascertainment. We attempted to model these differences in the four "studies" of KPD that used different criteria to choose the families.
