M. Ravinskaya¹, J. H. Verbeek¹, J. G. Daams¹, M. Langendam², C. T. J. Hulshof¹, I. Madan³, S. M. M. Verstappen⁴, M. Hagendijk¹, R. Kunz⁵, J. L. Hoving¹

¹Amsterdam UMC, University of Amsterdam, Department of Public and Occupational Health, Coronel Institute of Occupational Health, Amsterdam Public Health Research Institute, The Netherlands

²Amsterdam UMC, Academic Medical Center, University of Amsterdam, Department of Epidemiology and Data Science, Amsterdam Public Health Research Institute, The Netherlands

³Guy’s and St Thomas’ NHS Trust and King’s College London, Occupational Health Service Guy's and St Thomas' NHS Foundation Trust, UK

⁴Centre for Epidemiology Versus Arthritis, Faculty of Biology, Medicine and Health, The University of Manchester, UK

⁵Research Unit Evidence Based Insurance Medicine (EbIM), Department of Clinical Research, University of Basel and University of Basel Hospital, Switzerland

Background

This review is the first part of an initiative aiming to develop a COS for work participation and shows how work participation outcomes are measured in vocational and non-vocational RCTs for people with health problems.

Aims

To investigate how work participation outcomes in randomized controlled trials are measured internationally and across disciplines.

Methods

We identified trials that reported on work participation in Medline, Embase, PsycINFO and Cochrane Central published between 2014 and 2019. Screening, selection and data extraction were done by two authors independently. We grouped outcomes into four categories (“employment status”, “absence from work”, “at-work productivity loss” and “employability”) and created sub-categories according to how the outcome was measured.

Results

From 10,022 database hits we selected 269 trials reporting on 435 work participation outcomes. Authors used inconsistent outcome terminology to describe the measured constructs. Grouped in four main categories we identified 70 outcomes that reported on “employment status”, 196 on “absence from work” and return-to-work, 132 on “at-work productivity loss” and 37 on “employability” outcomes. Variability in measurement methods existed across all categories. Employment status and absenteeism measures consisted mostly of clinimetrically unvalidated tools. “At-work productivi¬ty loss” and “employability” were measured by at least 41 different questionnaires.

Conclusions

Extensive variability exists among trials in the measurement of outcomes, measurement methods and measurement instruments that focus on work participation. This study is a first step towards the development of a Core Outcome Set for work participation.