Need for recovery in the working population: Description and associations with fatigue and psychological distress

The absence of laboratory tests and clear criteria to identify homogeneous (sub)groups in patients presenting with unexplained fatigue, and to assess clinical status and disability in these patients, calls for further assessment methods. In the present study, a multi-dimensional approach to the assessment of chronic fatigue syndrome (CFS) is evaluated. Two-hundred and ninety-eight patients with CFS completed a set of postal questionnaires that assessed the behavioural, emotional, social, and cognitive aspects of CFS. By means of statistical analyses nine relatively independent dimensions of CFS were identified along which CFS-assessment and CFS-research can be directed. These dimensions were named: psychological well-being, functional impairment in daily life, sleep disturbances, avoidance of physical activity, neuropsychological impairment, causal attributions related to the complaints, social functioning, self-efficacy expectations, and subjective experience of the personal situation. A description of the study sample on these dimensions is presented.

The internal consistency, validity and factor structure of the 12-item General Health Questionnaire (GHQ-12) were investigated in a homogeneous sample consisting of 18-year-old males in Italy. The GHQ-12 proved to be a reliable instrument, as indicated by a Cronbach's alpha of 0.81. When the screening characteristics of the GHQ-12 (scored by the Likert method) were evaluated against the psychiatrist's ratings, the best balance between sensitivity and specificity was found at the GHQ cut-off score of 8/9: at this threshold, sensitivity was 0.68 and was paired to a specificity of 0.59 and an overall misclassification rate of 0.40. Validity coefficients based on a single severity score were rather low compared with those reported in other settings. When a principal components analysis with varimax (and oblimin) rotation was performed, two factors were identified: factor A (general dysphoria) was defined by 7 items related to anxiety and depression; factor B (social dysfunction) included 6 items testing the ability to perform daily activities and to cope with everyday problems. The identified factors revealed distinct ability in the discrimination between subjects with and without emotional disturbance according to the psychiatrist's ratings and correlated differently with 3 Minnesota Multiphasic Personality Inventory subscales (depression, D; conversion hysteria, Hy; psychasthenia, Pt). Thus, the factor structure of the GHQ-12 might provide useful information along with that offered by a single severity score, and the detection of cases might be improved by examining an individual's profile of scores on different subscales derived from factor analysis.

In the Netherlands, a large-scale prospective cohort study was started on prolonged fatigue in the working population. The 1st issue that had to be addressed was the determination of a cutoff point for fatigue for use in the working population. Fatigue is measured with the Checklist Individual Strength (CIS), a 20-item self-report questionnaire. This article demonstrates the process of decision making in the determination of the cutoff point. Total CIS scores were calculated, sensitivity and specificity were compared for potential cutoff points, and a receiver operating characteristics analysis was conducted. A CIS total cutoff point for fatigue of >76 was determined, with a specificity of 90% and a sensitivity of 73%. Limitations regarding the use of cutoff points are discussed. It is concluded that the defined cutoff point seems to be appropriate for use in the working population.