Specifying exposure classification parameters for sensitivity analysis: family breast cancer history

Abstract

One of the challenges to implementing sensitivity analysis for exposure misclassification is the process of specifying the classification proportions (eg, sensitivity and specificity). The specification of these assignments is guided by three sources of information: estimates from validation studies, expert judgment, and numerical constraints given the data. The purpose of this teaching paper is to describe the process of using validation data and expert judgment to adjust a breast cancer odds ratio for misclassification of family breast cancer history. The parameterization of various point estimates and prior distributions for sensitivity and specificity were guided by external validation data and expert judgment. We used both nonprobabilistic and probabilistic sensitivity analyses to investigate the dependence of the odds ratio estimate on the classification error. With our assumptions, a wider range of odds ratios adjusted for family breast cancer history misclassification resulted than portrayed in the conventional frequentist confidence interval.

Keywords:

• breast cancer
• family cancer history
• sensitivity analysis
• sensitivity
• specificity

Acknowledgements

The authors thank Dr Sander Greenland and the anonymous reviewers for helpful comments on an earlier draft. The authors report no conflicts of interest in this work. This study was supported in part by the Children’s Cancer Research Fund, Minneapolis, MN, USA (to AMJ).