Simultaneous screening for three correlated lipids in the VA HDL Intervention Trial

We developed methodology to design the multistage lipid screen for the VA HDL Intervention Trial, a randomized double-blind placebo-controlled secondary prevention clinical trial of 2531 participants. The trial aimed to determine if HDL-raising therapy reduces coronary events in men with low HDL-cholesterol and desirable LDL-cholesterol. Joint lipid distributions for HDL-cholesterol, LDL-cholesterol, and triglycerides were derived on the basis of estimates from previous studies, and simulations were performed to determine the cutpoints for excluding screenees for the three lipid parameters to be used at each recruitment stage. Operating characteristics for different screening rules are presented. Comparisons between the predicted and actual study recruitment results show good agreement in lipid characteristics and underscore the complexity of simultaneously screening on correlated continuous physiologic parameters such as lipids.