Commentary Focus: Study Design & Statistical Analysis Statistical relevance—relevant statistics,

S tatistical analysis is an importanttool in experimental research and isessential for the reliable interpreta-tion of experimental results. It is essential that statistical design should be considered at the very beginning of a research project, not merely as an afterthought. For example if the sample size for an experi-ment only allows for an underpowered statistical analysis, then the interpretation of the experiment will have to be limited. An experiment cannot be reverse engi-neered to become more statically signifi-cant, although experiments can of course be repeated independently to account for biological variation (see section on techni-cal versus biological replicates below)