Sample Size Calculation in Oncology Studies
Sample size calculation is at the core of study design. It is defined as the calculation of the minimum number of subjects to be included in a study in order to detect a true effect or value and must always to be performed a priori. Several aspects have to be considered when computing a sample size, including assumptions of expected outcomes in the control and experimental groups, type I and II error rates, power, and the dropout rate. Without proper sample size calculation, the results of a clinical study can be misleading, not generalizable to other settings, more likely to be false negative or false positive, and might even be associated with ethical implications. Additionally, careful planning and accurate reporting of this calculation ensures transparency and reliability and allows the reproducibility of results.
KeywordsClinical trials Randomized clinical trials Oncology Cancer Sample size