Data extraction Data extraction was performed by one reviewer and checked by another. This extraction was performed using a checklist that included items on (a) the self-report measure; (b) the health condition that the instrument intended to measure; (c) the presence of an explicit question to assess the work relatedness of the health condition; (d) study type; (e) the

reference standard (physician, test, or both) the self-report was compared with; (f) number and description of the CBL-0137 molecular weight population; (g) outcomes; (h) other considerations; (i) author and year; and (j) country. If an article described more than one study, the results GSK690693 supplier for each individual study were extracted separately. Assessment of method quality The included articles

were assessed for their quality by rating the following nine aspects against predefined criteria: aim of study, sampling, sample size, response rate, design, self-report before testing, interval between self-report and testing, blinding and outcome assessment (Table 1). The criteria were adapted from Hayden et al. (2006) and Palmer and Smedley (2007) to assess whether key study information was reported and the risk of bias was minimized. Articles were ranked higher if they were aimed at evaluation of self-report, well-powered,

D-malate dehydrogenase employed a representative sampling frame, achieved a highly effective response rate, were prospective or controlled, had a clear timeline with a short interval between self-report and examination, assessed outcome blinded to self-report, and had clear case definitions for self-report and outcome of examination/testing. Each of these qualities was rated individually and summarized to a final overall assessment per article translated into a quality score with a maximum of 23. We called a score high if it was 16 or higher: at least 14 points on aim of the study, sampling, sample size, response rate, design, interval, and outcome assessment combined and in addition positive scores for timeline and blinding of examiner. We called a score low if the summary score was 11 or lower. The moderate scores (12–15) are in between. The information regarding the characteristics of the studies, the quality and the results were synthesised into two additional tables (Tables 5, 6).