Imputing productivity gains from clinical trials.

Objective: To respond to employer and payer interest in the extent to which productivity gains offset therapy costs by identifying clinical trials that did not include such measures and using their clinical data to impute productivity impact.

Methods: A PubMed search identified the sample of 25 clinical trials of musculoskeletal pain medications and antidepressants. Next, we applied regression coefficients, quantifying the empirical relationship between clinical measures to each trial's clinical outcomes data. This validated methodology provides estimates of Work Limitations Questionnaire Productivity Loss scores.

Results: Based on imputation, musculoskeletal medications and antidepressants achieved median productivity gains of approximately 0.5% and 1.0%, respectively.

Conclusion: Accounting for productivity gains based on the Work Limitations Questionnaire could substantially influence cost-effectiveness results reported in the health economics literature.