Although productivity costs often represent a large proportion of the total cost related to health and healthcare interventions and several guidelines have stated that they should be included in health economic evaluations, in practice they are frequently ignored. A possible explanation for this discrepancy is that even though we now have various instruments available for measuring health-related productivity costs, the majority are not suited for use in economic evaluations.
The iMTA Productivity Cost Questionnaire (iPCQ) was recently designed to optimize the features of existing instruments, and to be a short generic outcome measure allowing for quantification and valuation of productivity costs. Prior research has confirmed the feasibility, face validity and partial reliability of the iPCQ. Our paper, however, is the first to investigate content and construct validity, as well as reliability of the entire questionnaire.
