About COS for Work


Mission statement

We intend to contribute to international, large scale evidence synthesis of interventions which impact work participation and help increase insight into the socio-economic burden of work-disability management.

What is the problem?

A lot of research is done within the field of occupational health with the aim of finding out which type of intervention is most effective in promoting work participation for people who experience a health problem. In some cases it is the primary aim of the trial; for example to find out if vocational rehabilitation helps people who are recovering from cancer and seek durable return to work. Other times, the primary aim of the trial is medical, but the intervention is expected to have an indirect effect on work outcomes as well. A primary aim of such a trial could be to compare surgical and nonsurgical treatment in patients with thoracolumbar fractures on not only several medical outcomes but also time to return to work . A major problem is that various definitions of similar work related concepts are used, as well as a variety of measurement methods. This prevents outcomes to be compared on a large scale.

Where is the gap?

Within the field of occupational health, ‘work participation’ is used as an umbrella term – it contains various types of work related outcome constructs and definitions. For example, when research is done about interventions to improve return to work for people who suffer from depression, several outcomes are used to measure the effectiveness of the interventions, such as: functional status, work functioning, productivity, workability, absenteeism, sick leave or return to work. Even though the aim is to measure to what extent people are able to (continue their) work, there is no guidance for researchers on how to choose an endpoint.

Moreover, not only is there no agreement on “what” to measure, but there is also no guideline which can be referred to on “how” to measure. This results in researchers using a variety of measurement instruments and measuring effectiveness at varying time-points. For example, while the term ‘sustainable employability’ is used in the field of occupational health, there is no official international consensus on when sustainable employment is achieved and how to measure it.

How will COS for Work help?

Once the same set of core outcomes is used, research waste and outcome reporting bias can be reduced, and higher levels of evidence synthesis can be achieved. This is also useful to help healthcare practitioners, guideline developers and policy makers to make better informed decisions.

Who can use COS for Work?

COS for Work can be used by trialists who perform studies on the effects of interventions which are targeted at workers with a health problem who are on sick leave or are not yet working. In addition, COS for Work can also be used by systematic reviewers of trials and guideline developers.

Our Approach

We follow the methodology of The Core Outcome Measures in Effectiveness Trials (COMET) initiative for the development of COS for Work. COMET was launched in 2010 in the United Kingdom with the aim to facilitate exchange of ideas and information for people who are interested in methodologically sound development and application of core outcome sets (www.comet-initiative.org). As of 2017 there were over 300 core outcome sets registered in the COMET database. The development of COS for Work is also registered in the COMET database (http://www.comet-initiative.org/studies/details/1195). For establishing the most effective measuring methods we use the approach made by Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) (www.cosmin.nl).

The development of COS for Work includes three systematic reviews on the topic of work participation, a survey among international experts/ stakeholders in the field of occupational health/insurance medicine, a focus group study and a Delphi study to reach consensus among experts/ stakeholders about the most suitable outcomes and outcome measurement instruments. Additionally, we plan to perform two projects on dissemination/ implementation and knowledge transfer.