Covariate imbalance and adjustment for logistic regression analysis of clinical trial data

J Biopharm Stat. 2013;23(6):1383-402. doi: 10.1080/10543406.2013.834912.

Abstract

In logistic regression analysis for binary clinical trial data, adjusted treatment effect estimates are often not equivalent to unadjusted estimates in the presence of influential covariates. This article uses simulation to quantify the benefit of covariate adjustment in logistic regression. However, International Conference on Harmonization guidelines suggest that covariate adjustment be prespecified. Unplanned adjusted analyses should be considered secondary. Results suggest that if adjustment is not possible or unplanned in a logistic setting, balance in continuous covariates can alleviate some (but never all) of the shortcomings of unadjusted analyses. The case of log binomial regression is also explored.

MeSH terms

  • Brain Ischemia / diagnosis
  • Brain Ischemia / drug therapy
  • Clinical Trials as Topic / statistics & numerical data*
  • Computer Simulation
  • Data Interpretation, Statistical*
  • Fibrinolytic Agents / administration & dosage
  • Humans
  • Logistic Models*
  • Numerical Analysis, Computer-Assisted
  • Odds Ratio
  • Research Design / statistics & numerical data
  • Severity of Illness Index
  • Stroke / diagnosis
  • Stroke / drug therapy
  • Thrombolytic Therapy
  • Tissue Plasminogen Activator / administration & dosage
  • Treatment Outcome

Substances

  • Fibrinolytic Agents
  • Tissue Plasminogen Activator