A. G. E. M. de Boer

Is a single-item visual analogue scale as valid, reliable and responsive as multi-item scales in measuring quality of life?

Purpose: To compare the validity, reliability and responsiveness of a single, global quality of life question to multi-item scales. Method: Data were obtained from 83 consecutive patients with oesophageal adenocarcinoma undergoing either transhiatal or transthoracic oesophagectomy. Quality of life was measured at baseline, 5 weeks, 3 and 12 months post-operatively with a single-item Visual Analogue Scale (VAS) ranging from 0 to 100, the multi-item Medical Outcomes Study Short Form-20 (MOS SF-20) and Rotterdam Symptom Check-List (RSCL). Convergent and discriminant validity, test–retest reliability and both distribution-based and anchor-based responsiveness were evaluated. Major findings: At baseline and at 5 weeks, the VAS showed high correlations with the MOS SF-20 health perceptions scale (r = 0.70 and 0.72) and moderate to high correlations with all other subscales of the MOS SF-20 and RSCL (r = 0.29–0.70). The test–retest reliability intra-class correlation for the VAS was 0.87. At 5 weeks post-operatively, the distribution-based responsiveness was moderate for the VAS (standardised response mean: −0.47; effect size: −0.56), high for the physical subscales of the MOS SF-20 and RSCL (−1.08 to −1.51) and low for the psychological subscales (0.11 to −0.25). Five weeks post-operatively, anchor-based responsiveness was highest for the VAS (r = 0.54). Conclusion: The VAS is an instrument with good validity, excellent reliability, moderate distribution-based responsiveness and good anchor-based responsiveness compared to multi-item questionnaires. Its use is recommended in clinical trials to assess global quality of life.

Quality of life in patients with Parkinson's disease: development of a questionnaire.

OBJECTIVES--To develop and test a questionnaire for measuring quality of life in patients with Parkinsons disease. METHODS--An item pool was developed based on the experience of patients with Parkinsons disease and of neurologists; medical literature on the problems of patients with Parkinsons disease; and other quality of life questionnaires. To reduce the item pool, 13 patients identified items that were a problem to them and rated their importance. Items which were most often chosen and rated most important were included in the Parkinsons disease quality of life questionnaire (PDQL). The PDQL consists of 37 items. To evaluate the discriminant validity of the PDQL three groups of severity of disease were compared. To test for convergent validity, the scores of the PDQL were tested for correlation with standard indices of quality of life. RESULTS--The PDQL was filled out by 384 patients with Parkinsons disease. It consisted of four subscales: parkinsonian symptoms, systemic symptoms, emotional functioning, and social functioning. The internal-consistency reliability coefficients of the PDQL subscales were high (0.80-0.87). Patients with higher disease severity had significantly lower quality of life on all PDQL subscales (P < 0.05). Almost all PDQL subscales correlated highly (P < 0.001) with the corresponding scales of the standard quality of life indices. CONCLUSION--The PDQL is a relevant, reliable, and valid measure of the quality of life of patients with Parkinsons disease.

Work ability and return-to-work in cancer patients

The extent to which self-assessed work ability collected during treatment can predict return-to-work in cancer patients is unknown. In this prospective study, we consecutively included employed cancer patients who underwent treatment with curative intent at 6 months following the first day of sick leave. Work ability data (scores 0–10), clinical and sociodemographic data were collected at 6 months, while return-to-work was measured at 6, 12 and 18 months. Most of the 195 patients had been diagnosed with breast cancer (26%), cancer of the female genitals (22%) or genitourological cancer (22%). Mean current work ability scores improved significantly over time from 4.6 at 6 months to 6.3 and 6.7 at 12 and 18 months, respectively. Patients with haematological cancers and those who received chemotherapy showed the lowest work ability scores, while patients with cancer of urogenital tract or with gastrointestinal cancer had the highest scores. Work ability at 6 months strongly predicted return-to-work at 18 months, after correction for the influence of age and treatment (hazard ratio=1.37, CI 1.27–1.48). We conclude that self-assessed work ability is an important factor in the return-to-work process of cancer patients independent of age and clinical factors.

Quality of Life After Transhiatal Compared With Extended Transthoracic Resection for Adenocarcinoma of the Esophagus

PURPOSE To assess 3 years of quality of life in patients with esophageal cancer in a randomized trial comparing limited transhiatal resection with extended transthoracic resection. PATIENTS AND METHODS Quality-of-life questionnaires were sent at baseline and at 5 weeks; 3, 6, 9, and 12 months; and 1.5, 2, 2.5, and 3 years after surgery. Physical and psychological symptoms, activity level, and global quality of life were assessed with the disease-specific Rotterdam Symptom Checklist. Generic quality of life was measured with the Medical Outcomes Study Short Form-20. RESULTS A total of 199 patients participated. Physical symptoms and activity level declined after the operation and gradually returned toward baseline within the first year (P < .01). Psychological well-being consistently improved after baseline (P < .01), whereas global quality of life showed a small initial decline followed by continuous gradual improvement (P < .01). Quality of life stabilized in the second and third year. Three months after the operation, patients in the transhiatal esophagectomy group (n = 96) reported fewer physical symptoms (P = .01) and better activity levels (P < .01) than patients in the transthoracic group (n = 103), but no differences were found at any other measurement point. For psychological symptoms and global quality of life, no differences were found at any follow-up measurement. A similar pattern was found for generic quality of life. CONCLUSION No lasting differences in quality of life of patients who underwent either transhiatal or transthoracic resection were found. Compared with baseline, quality of life declined after the operation but was restored within a year in both groups.

Determinants of work ability and its predictive value for disability

BACKGROUND Maintaining the ability of workers to cope with physical and psychosocial demands at work becomes increasingly important in prolonging working life. AIMS To analyse the effects of work-related factors and individual characteristics on work ability and to determine the predictive value of work ability on receiving a work-related disability pension. METHODS A longitudinal study was conducted among 850 construction workers aged 40 years and older, with average follow-up period of 23 months. Disability was defined as receiving a disability pension, granted to workers unable to continue working in their regular job. Work ability was assessed using the work ability index (WAI). Associations between work-related factors and individual characteristics with work ability at baseline were evaluated using linear regression analysis, and Cox regression analysis was used to evaluate the predictive value of work ability for disability. RESULTS Work-related factors were associated with a lower work ability at baseline, but had little prognostic value for disability during follow-up. The hazard ratios for disability among workers with a moderate and poor work ability at baseline were 8 and 32, respectively. All separate scales in the WAI had predictive power for future disability with the highest influence of current work ability in relation to job demands and lowest influence of diseases diagnosed by a physician. CONCLUSION A moderate or poor work ability was highly predictive for receiving a disability pension. Preventive measures should facilitate a good balance between work performance and health in order to prevent quitting labour participation.

Supervisory behaviour as a predictor of return to work in employees absent from work due to mental health problems

Aims: To study supervisory behaviour as a predictive factor for return to work of employees absent due to mental health problems; and to explore the association between conditional factors and supervisory behaviour. Methods: Eighty five supervisors of employees were interviewed by telephone. Questionnaires providing information on person related factors, depressive symptoms, and sickness absence were sent to the employees at baseline, three months, six months, and after one year. Three aspects of supervisory behaviour during the period of absence were measured: communication with the employee, promoting gradual return to work, and consulting of other professionals. Results: Better communication between supervisor and employee was associated with time to full return to work in non-depressed employees. For employees with a high level of depressive symptoms, this association could not be established. Consulting other professionals more often was associated with a longer duration of the sickness absence for both full and partial return to work. If sickness absence had financial consequences for the department, the supervisor was more likely to communicate frequently with the employee. Supervisors who were responsible for return to work in their organisation were more likely to communicate better and to consult more often with other professionals. Conclusion: Supervisors should communicate more frequently with employees during sickness absence as well as hold follow up meetings more often as this is associated with a faster return to work in those employees.

The Depression Anxiety Stress Scales (DASS): detecting anxiety disorder and depression in employees absent from work because of mental health problems

Aims: To (1) evaluate the psychometric properties and (2) examine the ability to detect cases with anxiety disorder and depression in a population of employees absent from work because of mental health problems. Methods: Internal consistency, construct validity, and criterion validity of the Depression Anxiety Stress Scales (DASS) were assessed. Furthermore, the ability to identify anxiety disorders or depression was evaluated by calculating posterior probabilities of these disorders following positive and negative test results for different cut off scores of the DASS-Depression and DASS-Anxiety subscales. Results: Internal consistency of the DASS subscales was high, with Cronbach’s alphas of 0.94, 0.88, and 0.93 for depression, anxiety, and stress respectively. Factor analysis revealed a three factor solution, which corresponded well with the three subscales of the DASS. Construct validity was further supported by moderately high correlations of the DASS with indices of convergent validity (0.65 and 0.75), and lower correlations of the DASS with indices of divergent validity (range −0.22 to 0.07). Support for criterion validity was provided by a statistically significant difference in DASS scores between two diagnostic groups. A cut off score of 5 for anxiety and 12 for depression is recommended. The DASS showed probabilities of anxiety and depression after a negative test result of 0.05 and 0.06 respectively. Probabilities of 0.29 for anxiety disorder and 0.33 for depression after a positive test result reflect relatively low specificity of the DASS. Conclusion: The psychometric properties of the DASS are suitable for use in an occupational health care setting. The DASS can be helpful in ruling out anxiety disorder and depression in employees with mental health problems.

Return-to-work interventions integrated into cancer care: a systematic review

Objectives The purpose of this study was to review the literature on the content of interventions focusing on return to work, employment status, or work retention in patients with cancer. Furthermore, the effect of the interventions on return to work was assessed in studies reporting return to work. Methods A literature search was conducted using the databases MEDLINE, PsycINFO, EMBASE and CINAHL. Articles that described a work-directed intervention focusing on return to work, employment status, or work retention in patients with cancer were included. The content of the work-directed part of the interventions was assessed based on two criteria for content analysis: 1. does the setting fit the shared care model of cancer survivor care? 2. Does the intervention target work ability and physical workload? For studies reporting return-to-work outcomes, the return-to-work rates were assessed. For studies that used a control group the ORs and the 95% CIs were calculated. Results Twenty-three articles describing 19 interventions met the inclusion criteria. Seven studies reported return-to-work outcomes of which four used a control group. Only three interventions aimed primarily at enhancing return to work or employment status. The most frequently reported work-directed components were encouragement, education or advice about work or work-related subjects (68%), vocational or occupational training (21%), or work accommodations (11%). One intervention fit the shared care model of cancer survivor care and five interventions enhanced work ability or decreased physical workload. The rate of return to work ranged from 37% to 89%. In one of the four controlled studies the intervention increased return to work significantly and in the other studies the results were insignificant. Conclusions Only few interventions are primarily aimed at enhancing return to work in patients with cancer and most do not fit the shared care model involving integrated cancer care. Future studies should be developed with well-structured work-directed components that should be evaluated in randomised controlled trials.

An occupational health intervention programme for workers at risk for early retirement; a randomised controlled trial

Aims: To evaluate an occupational health intervention programme for workers at risk for early retirement. Methods: Between April 1997 and May 1998, 116 employees of a large company who were older than 50 years indicated that they would not be able to work up to their retirement. They were randomly assigned to an intervention (n = 61) or control group (n = 55). The intervention programme lasted six months and was executed by an occupational physician. Job position and number of sick leave days after two years were collected from the company’s computer database. A questionnaire was sent to the employees at baseline, after six months, and after two years; it included the Work Ability Index, the Utrecht Burn Out Scale, and the Nottingham Health Profile measuring quality of life. Results: Fewer employees (11%) in the intervention group retired early than in the control group (28%). The total average number of sick leave days in two years was 82.3 for the intervention group and 107.8 for the control group. Six months after baseline, employees in the intervention group had better work ability, less burnout, and better quality of life than employees in the control group. Two years after randomisation no differences between the two groups were found. Conclusions: This occupational health intervention programme proved to be a promising intervention in the prevention of early retirement.

Patient satisfaction with occupational health physicians, development of a questionnaire

Aims: To develop a questionnaire that measures specific aspects of patient satisfaction with occupational health physicians. Methods: General patient satisfaction questionnaires, a literature survey, and interviews with patients were used. An initial questionnaire was distributed among sick listed patients (n = 432) of occupational physicians (n = 90) from different occupational health services. To reduce items and to develop scales exploratory factor analysis and reliability analysis was used. A linear regression model was used to predict satisfaction ratings from the scales of the questionnaire. Results: Questions about independence of the occupational physician were difficult to ask unambiguously. The factor analysis revealed five relevant factors which were named “being taken seriously as a patient”, “attitude towards occupational health services”, “trust and confidentiality”, “expectations”, and “comfort and access”. All scales could be reduced to a maximum of five items without reducing the scale reliability too much. In the regression analysis, 71% of the variance of satisfaction ratings was explained by the first four scales and most by the first scale. “Comfort and access” did not contribute significantly to the model. Conclusions: A short questionnaire was developed to measure different aspects of patient satisfaction specific for occupational health. Whether the questionnaire can effectively lead to quality improvement in occupational health services should be investigated.