Tuesday, July 21, 2009

Checklist for preparing a Statistical Analysis Plan for Clinical Trials

Checklist for preparing a Statistical Analysis Plan for Clinical Trials...

  • Provide a detailed description of the primary and secondary endpoints and how they are to be measured.
  • Provide details of the statistical methods and tests that will be used to analyze the endpoints. The analysis of the primary outcome must follow the principle of intention-to-treat.
  • Describe the strategy to be used (e.g., alternative statistical procedures) if the distributional or test assumptions are not satisfied.
  • Detail whether comparisons will be one-tailed or two-tailed (with appropriate justification if necessary) and specify the level of significance to be used.
  • Identify whether any adjustment to the significance level or the final P values will be made to account for any planned or unplanned multiple testing or subgroup analyses.
  • Specify potential adjusted analyses with a statement of which covariates or factors will be included.
  • Identify any planned subgroup or subset analysis along with justification for the relevance of this analysis (eg, biological rationale) before commencement of the trial.
  • Specify planned exploratory analyses, justifying their importance.
  • Support claimed differential subgroup effects with biological rationale and supporting evidence from within and outside the study.
  • Provide statistical evidence of interaction between the overall treatment effect and that observed in the subgroup(s) of interest.
  • Remember that pre-specified subgroups will have more interpretive value than those defined on an ad-hoc basis or as a result of multiple comparisons.