What test can be performed to compare the percentage of participants who developed abnormal triglyceride levels between the vitamin A group and the trace group? 

Ophthalmology

One interesting aspect of the study described in Problem 10.68 is to assess changes in other parameters as a result of supplementation with vitamin A. One quantity of interest is the level of serum triglycerides. Researchers found that among 133 participants in the vitamin A group (males and females combined) who were in the normal range at  baseline (<2.13 μmol/L), 15 were above the upper limit of normal at each of their last 2 consecutive study visits. Similarly, among 138 participants in the trace group who were in the normal range at baseline (<2.13 μmol/L), 2 were above the upper limit of normal at each of their last two consecutive study visits [19].