undetermined power of statistical tests why the undetermined power of statistical tests does not imply equivalence? retrospective study meaning of absence of significant difference what is the undetermined power of statistical tests why do retrospective tests have undetermined power when undetermined power is used in a retrospective study what was an undetermined power study? what is undetermined power of a study retrospective study of treatment without significant difference undetermined power of a statistical test is an example of what is meant by undetermined power? what is meant by the absence of a significant difference does not imply equivalence because of the undetermined power of statistical tests? what is meant by the lack of a significant difference does not imply equivalence what is undetermined power of the statistical tests why is there no significant difference between treatments in a retrospective clinical study? what is meant by lack of a significant difference undetermined power undetermined power of statistical study meaning why are studies retrospective in nature retrospective medical study definition