Analysis of lab data is one of the major safety evaluations conducted during clinical trials. Lab results are displayed in the data listings and summarized using tables. These reports are customary for longitudinal data analysis (descriptive summary statistics for major lab parameters and their calculated changes from baseline). Another common type of analysis of lab data is evaluating shifts from baseline. In oncology, shift in toxicity (according NCI CTC AE guidance) is commonly used to determine how the categorical result varies from baseline to post-dose. For some of the lab parameters, toxicity is irrelevant; for some, it is expected in only one direction; and for several others, toxicity can be bi-directional (separate types of toxicity due to increase and due to decrease over normal range). This article discusses how to create an effective ADLB that answers all of the challenges in analysis of lab data.