ABSTRACT
This chapter provides a description of some challenges that may be encountered in the analysis of biomarker data, and offers advice on how best to deal with these challenges. The validity of a biomarker is defined to be the extent to which it measures what it is intended to measure. The chapter also provides guidance for selecting the appropriate statistical method to use to measure the association between exposure and outcome. It is primarily devoted to appropriate methods of analysis of biomarker data. The chapter focuses on the issues of sample size determination as needed since even the most carefully selected statistical procedures will not perform properly if the sample size is too small. It addresses three challenges frequently encountered when correlation coefficients are used in the analysis of biomarker data: proper methods of analysis and interpretation of the results, sample size determination, and comparison of related correlation coefficients.
