Considerations for evaluating and recommending worker productivity outcome measures : an update from the OMERACT worker productivity group

Objective. The Outcome Measures in Rheumatology (OMERACT) Worker Productivity Group continues efforts to assess psychometric properties of measures of presenteeism. Methods. Psychometric properties of single-item and dual answer multiitem scales were assessed, as well as methods to evaluate thresholds of meaning. Results. Test-retest reliability and construct validity of single item global measures was moderate to good. The value of measuring both degree of difficulty and amount of time with difficulty in multi-items questionnaires was confirmed. Thresholds of meaning vary depending on methods and external anchors applied. Conclusion. We have advanced our understanding of the performance of presenteeism measures and have developed approaches to describing thresholds of meaning.