Practical Considerations in Clinical Pathology Data Interpretation and Description: The Use of Statistics, Reference Intervals, and Severity Descriptors

Although interpretation and description of clinical pathology test results for any preclinical safety assessment study should employ a consistent standard approach, companies differ regarding that approach and the appearance of the end product. Some rely heavily on statistical analysis, others do not. Some believe reference intervals are important, most do not. Some prefer severity of effects be described by percentage differences from, or multiples of, baseline or control, others prefer only word modifiers. Some expect a definitive decision for every potential effect, others accept uncertainty. This commentary addresses these differences and underscores the need for flexibility in a consistent standard approach because the conditions of every study are unique. This article constitutes an overview of material originally presented at Session 2 of the 2016 Society of Toxicologic Pathology Annual Symposium.