Study design and data analysis in clinical and environmental models of nephrotoxicity

Protocols for clinical studies of nephrotoxicity may include several elements. They include background information, study objectives, study design, data handling and analysis, organization and administration, and methods and definitions. Response variables used to indicate the development of clinically apparent renal disease should be clearly defined. Susceptibility factors such as diabetes, hypertension, cardiovascular disease, obesity, smoking history, and genetic factors may influence the development of renal disease and other health outcomes. These factors may also affect the pattern of abnormal biomarkers that appear during the development of renal disease. Some individuals who are normal by standard clinical criteria will be in various stages of disease development and will have abnormal biomarker levels. With all approaches, an adequate baseline assessment of biomarker values is critically important. Consistent findings among studies reinforce conclusions.