Evaluation of risk scores derived from the health family tree program.

Family health history is an independent risk factor for certain diseases. The Health Family Tree (HFT) was developed and used to document and assess family health history from the families of high school students since 1980. While the risk algorithm of the HFT was initially validated, 20 years of use as a public health tool in the community provides an extremely large dataset for more rigorous validation. A retrospective cohort study was used with the events before the "cut-off" year as the baseline and the events after the "cut-off" year as the follow-up. Baseline data were used in the algorithm to calculate the Family History Score (FHS). Cox proportional hazards model was used to test the dose-response nature of the FHS for predicting incident events. An FHS >/=1 was determined to be a significant predictor for future development of diabetes, myocardial infarction, and early onset of myocardial infarction.