Changes in symptom severity, schemas and modes in heterogeneous psychiatric patient groups following short-term schema cognitive-behavioural group therapy: a naturalistic pre-treatment and post-treatment design in an outpatient clinic.

UNLABELLED: Schema therapy has proven to be an effective treatment for patients with borderline personality disorder. However, little is known of its merits in other psychiatric (personality) disorders. OBJECTIVE: This study investigated whether schema therapy in a group setting (group schema cognitive-behavioural therapy [SCBT-g]) was associated with changes in symptom and schema and mode severity. Furthermore, the aim was to search for baseline predictors and possible mediators of treatment outcome. DESIGN AND METHOD: Sixty-three heterogeneous psychiatric outpatients who attended the SCBT-g were included as participants. In this naturalistic pre-treatment and post-treatment design, data were available on the Symptom Checklist 90, the Schema Questionnaire and the Young-Atkinson Mode Inventory. RESULTS: All outcome measurements showed changes with moderate to high effect sizes, with 53.2% of the patients showing a significant reduction in severity of psychiatric symptoms and schemas and modes. Higher pre-treatment levels of the schema domain Other Directedness predicted greater symptom reduction. Pre-treatment to mid-treatment changes in schema severity predicted subsequent symptom improvement, but change in symptoms and schemas proved to be strongly correlated. CONCLUSIONS: In this naturalistic study, SCBT-g was associated with reduced symptom and schema and mode severity in more than half of the psychiatric outpatients. Furthermore, the results suggest that changes in schemas and symptomatology mutually reinforce each other. KEY PRACTITIONER MESSAGE: Over 50% of ambulatory patients show clinical improvement after treatment in a short-term schema therapy group. Other Directedness seems to be a predictor of schema group therapy success. More randomized controlled trial studies and prediction and mediation studies on (short-term) schema group therapy are sorely needed.

Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control.

OBJECTIVES: Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. METHODS: From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. RESULTS: The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. CONCLUSIONS: Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.

Questionnaire surveys on health and working conditions: development of an instrument for risk assessment in companies.

Periodic Occupational Health Surveys (POHS) are frequently used by occupational health and safety services in the Netherlands as a risk assessment instrument. These surveys include a questionnaire on work and health. Systematic attention is paid in this questionnaire to a broad range of working conditions and health complaints. In this article a method is presented to identify and evaluate work risks and health problems in groups of workers. Working conditions and health in any given company or department are assessed by comparing questionnaire data from its worker populations with data from one or more reference populations. Significant differences are interpreted as signals for both adverse working conditions and health problems. Considerations and choices with regard to the technical, operational and strategic quality of the method are elucidated. Probabilities of alpha- and beta-errors, choice of significance levels, and selection of reference populations are dealt with. Finally, a way of presentation of the results is shown. The method is considered to be part of a broader approach toward risk assessment. We recommend the combined use of questionnaire results and other available information, such as workplace surveys and sickness absence data. Questionnaires about work and health can be seen as one step in a multi-phase design: like in many diagnostic processes, the latter phases can enhance the precision of previous results. Recommendations are made for validating and evaluating this instrument.

Revealing response shift in longitudinal research on fatigue--the use of the thentest approach.

In this study we examined whether response shift resulting from changes in internal standards occurs in cancer patients undergoing radiotherapy. Ninety-nine newly diagnosed patients undergoing radiotherapy were administered two standardized self-report measures of fatigue prior to receiving radiotherapy. After completion of radiotherapy, patients filled out these questionnaires as a conventional posttest and in reference to how they perceived themselves as they were prior to radiotherapy (a so-called 'thentest'). A transition (direct change) score on fatigue was used as a stratification measure. Patients were subsequently interviewed about their responses. The pattern of mean scores indicative of response-shift effects was found in two distinct subgroups: patients experiencing diminishing levels of fatigue and patients facing early stages of adaptation to increased levels of fatigue. Since response shift may adversely affect the results of self-reported outcomes in clinical trials or other longitudinal research, further research is very much needed.

Occupational classification according to work demands: an evaluation study.

The use of job title as crude exposure measure in epidemiological studies is often inevitable when the available exposure data is scarce. In this study, an existing classification scheme of all job titles in the Netherlands into six categories of physical and mental work demands, constructed by expert judgement, was evaluated. Furthermore, a revision of this classification scheme for a research project on the relation between age, physical work demands, and musculoskeletal complaints was proposed and evaluated as well. For the evaluation, self-reported work demands, derived from questionnaire data of 38,921 employees and quantified by a scale of physical work demands and mental work demands, were used. Based on comparison of the mean scale scores of the several categories of work demands at group level, both classification schemes showed construct validity. Notwithstanding several limitations, the use of the presented classification schemes in epidemiological studies seems particularly challenging and rewarding when analysing data at group level from large and heterogeneous occupational populations. These kind of exploratory studies may generate new hypothesis on the basic patterns concerning work-related disorders, and can also be informative from a policy making perspective.

Musculoskeletal complaints in The Netherlands in relation to age, gender and physically demanding work.

OBJECTIVES: This cross-sectional study was performed in order to elucidate the relationship of musculoskeletal complaints with age, gender and physically demanding work in the Netherlands. METHODS: Questionnaire data of male (n = 36756) and female (n = 7730) employees, gathered as part of periodical occupational health surveys among active workers in the Netherlands, were stratified for age, gender, and type of work demands. For each stratified group prevalence rates (PR) were calculated for complaints of the back, neck, upper and lower extremities. Moreover, prevalence rate differences (PRD) were estimated as an absolute effect measure of exposure to various types of physical work demands, with active employees in mentally demanding work acting as a reference population. RESULTS: Musculoskeletal complaints among workers in physically demanding occupations were found to increase with age for both sexes. For several complaints, substantially higher rates were reported for women than for men, with a relatively high number of complaints observed among the older female workers (around 40% for complaints of back, upper and lower extremities). Significant PRDs were present in particular for employees in heavy physically demanding occupations and in jobs with mixed mental and physical work demands. CONCLUSIONS: With the ageing of the workforce in mind, these findings stress the need for implementation of preventive measures. Special attention towards the susceptible group of female employees, the elderly age groups in particular, seems justified. In order to clarify the combined effects of age and physical work demands on musculoskeletal complaints, additional studies are required.

Repeated survey on changes in musculoskeletal complaints relative to age and work demands.

OBJECTIVES: To examine changes in musculoskeletal complaints over four years in groups of employees relative to age and work demands. METHODS: Repeated questionnaire data of male employees in heavy physical work (exposed group, n = 7324) and mental work (control group, n = 4686), stratified for age (20-9, 30-9, 40-9, 50-9), were analysed. For each employee, data on the occurrence of musculoskeletal complaints from two surveys with a mean interval of around four years were available. Changes in prevalences over the follow up interval were analysed. Proportions of new, recovered, and chronic cases as well as those free of complaints at both surveys were studied. RESULTS: For most complaints, there were significantly greater increases in prevalences in the exposed group compared with the control group over the follow up interval particularly within the group aged 40-9 for back, neck, and several sites of the upper and lower limbs. The 20-9 year age group also had significantly greater changes for several musculoskeletal complaints. Within the oldest age group (50-9) exposure to heavy physical work demands only affected changes in prevalences of neck and upper arm complaints. After four years in the cohort free of complaints at the start of the follow up the group aged 40-9 had the highest prevalence of complaints of the back, neck, and the upper and lower limbs. CONCLUSIONS: Middle aged and younger employees develop musculoskeletal complaints as a result of exposure to heavy physical work. In the oldest age group health related selection seems to mask the occupational health risks under study. To prevent the expected increase in musculoskeletal disorders and related work disability in our aging workforce, preventive measures should be taken at all stages of a working life.

Selection related to musculoskeletal complaints among employees.

OBJECTIVES: To (a) describe differences in the outcome of cross sectional and longitudinal analysis on musculoskeletal complaints relative to age and work demands, and (b) to assess the entrance and drop out selection on musculoskeletal complaints among groups of employees relative to age and work demands. METHODS: A study population was selected on the basis of questionnaire data from periodical occupational health surveys of almost 45,000 employees collected between 1982 and 1993. From all companies within this data base that participated twice in company wide surveys four years apart, male employees were selected, and stratified for age and work demands. There were several populations: follow up (participation in both surveys); drop out (participation only in the first survey); entrance (participation only at the second survey); and two cross sectional populations (all participants at each survey). Prevalences of back complaints and turnover rates were analysed. RESULTS: Reported back complaints in the cross sectional analysis declined over the oldest age groups in heavy physical work versus a small increase in the longitudinal analysis. The age group 50-9 and back complaints were identified as predictors at the first survey for not participating at the second survey. Neither age nor work demands at the first survey indicated drop out among those employees with back complaints at the first survey. The effects of entrance selection on estimated prevalences were small. CONCLUSIONS: The results indicate that musculoskeletal disorders lead to selection out of work, affecting the validity of both cross sectional and longitudinal epidemiological studies. In future studies analyses of turnover figures on musculoskeletal complaints relative to work demands and age are recommended.

Health complaints and working conditions experienced in relation to work and age.

OBJECTIVES: The main objective is to describe the potential health and work problems of the aging employees in the Dutch working population. In this way, we can identify groups at extra risk of specific health problems. METHODS: In The Netherlands, occupational health services gather questionnaire data about work and health as part of periodical occupational health surveys (POHSs). These data from the POHSs of complaints about health and working conditions, aggregated into occupational groups and age categories, are used to provide indications for groups at extra risk of specific health problems. These problems are assessed by overviews of the relation between age and complaints about health and working conditions. RESULTS: Almost all of the health questions show an increase in health complaints with increasing age. White collar workers, especially the high grade white collar workers, usually have lower complaint percentages on health questions than blue collar workers. Female employees have relatively high complaint percentages on the health questions. Differences between occupational groups in the complaints about work and working conditions reflect the differences in work demands and exposure. The relation between age and work complaints is generally inconsistent and weak. The complaint percentages on work questions of female employees tend to be equal to or lower than those of the male employees. CONCLUSIONS: The absence of a clear increase of work complaints with advancing age in the presence of a decrease in health and working capacity may be explained by a selective turnover in the working population, especially in demanding occupations. To enhance the work participation of older employees it may be necessary to reduce the work demands and to increase decision latitude.

Physical work load and gestational age at delivery.

OBJECTIVE: To assess the impact of physical activity on the gestational age at delivery in women performing physical tasks in their jobs during pregnancy. METHODS: Qualified nurses at 15 weeks of pregnancy were asked through a questionnaire to describe the tasks in their regular job, the physical activities involved, and their exposure to other occupational stressors. The physical activities to be identified were walking, standing, lifting, stooping, squatting, and sitting. RESULTS: A high degree of daily physical work load during pregnancy seemed to be a significant predictor for the gestational age at delivery, whereas chemical and infectious agents were not. CONCLUSIONS: Physical work load during pregnancy should be diminished to avoid adverse effects on gestational age at delivery.

The Atlas of Health and Working Conditions by Occupation. 1. Occupational ranking lists and occupational profiles from periodical occupational health survey data.

In this article, we describe methods which have been applied in the compilation of the Atlas of Health and Working conditions by Occupation. First, we discuss the need for information systems to identify problems concerning working conditions and health. Such information systems have an exploratory purpose, being deployed to identify work risks in companies, groups of occupations and sectors of industry, and can also be a starting point for the generation of hypotheses on the causes of adverse health effects. In the Netherlands, occupational health services gather questionnaire data about work and health as part of periodical occupational health surveys. In the atlas, aggregated questionnaire data for 129 occupations with male employees and 19 occupations with female employees are presented. In this article, we explain the methodology used to compare occupations with regard to each item in the questionnaire. We then discuss applications of these occupational ranking lists. The cross-sectional nature of the data collection, various forms of selection and the limited size of some occupational populations have to be taken into account when interpreting the results. Occupational ranking lists can be applied in the allocation of resources and in the design of scientific research. The overviews for each occupation, presented in the second half of the atlas, provide an occupational profile of existing problems with respect to work and health. These profiles are used as basic information to develop a practical policy on working conditions and health.

The Atlas of Health and Working Conditions by Occupation. 2. A comparison with the "Atlas of Health and Working Conditions in the Construction Industry".

The results of the general Atlas of Health and Working Conditions by Occupation were compared with the results of the Atlas of Health and Working Conditions in the Construction Industry. Both are based on questionnaire data from periodical occupational health surveys [POHSs]. The scores on most of the items showed considerable differences between the two atlases, partly due to differences in the regional origin of the data. Therefore, direct comparisons between the atlases are biased by regional differences. To study the reliability and the generalizability of the results of both atlases, similarities between the data files with respect to occupations in the construction industry were studied. Most of the items on working conditions, especially those with a widespread distribution, showed a close resemblance between the data files in terms of the relative position of an occupation compared to other occupations in the construction industry. The items on health showed less resemblance, except for the items on musculoskeletal complaints, which showed results similar to those of the work items. These results indicate the reliability and generalizability of the judgements based on both atlases outside the regions of origin, as far as items with a widespread distribution are concerned. Therefore, we recommend the aggregation of POHS data on a national scale, taking regional differences into account. In that way, a greater number of occupations will be described and the reliability of the results will be enhanced.

Do smokers get more back pain?

Recently smoking has been increasingly implicated as a possible risk factor for low-back pain. One explanation for this finding is confounding by occupation. To investigate this possibility, the relationship between smoking and self-reported back pain was studied within 13 occupations. A relationship between smoking and back pain was observed only in occupations that require physical exertion. The relationship between smoking and other musculoskeletal pain also was explored. Pain in the extremities turned out to be related more clearly to smoking than to pain in the neck or the back. This suggests confounding or a general influence of smoking on pain. It is concluded that prevention of back pain could be a beneficial side-effect of anti-smoking campaigns. However, the prime target for prevention of low-back pain would have to be other factors.

A comparison of dilution adjustment methods for urinary enzymes.

Urinary dilution adjustment methods can be used to reduce the intra-individual variability in concentrations of metals and other substances in urine due to variability in urinary flow. In this study linear and non-linear dilution adjustments with urinary flow, creatinine (CREAT) and urinary density (UD) were compared for the urinary enzymes alanine amino peptidase (AAP), beta-galactosidase (beta GAL) and N-acetyl-beta, D-glucosaminidase (NAG). The most optimal dilution adjustment for AAP was: AAPadjusted = AAPmeasured/(CREATmeasured)0.824 The optimal dilution adjustment for beta GAL was: beta GALadjusted = beta GALmeasured/(CREATmeasured)0.878 For NAG the optimal dilution adjustment parameter was the conventional linear adjustment with SG. It could not be determined whether urinary dilution methods can be useful for population based reference intervals of urinary enzymes. If personal reference intervals can be calculated, urinary dilution adjustment methods may be useful by reduction of intraindividual variability.

Semi-quinone formation from the catechol and ortho-quinone metabolites of the antitumor agent VP-16-213.

The catechol metabolite of the antitumor agent VP-16-213 and the ortho-quinone of VP-16-213--a secondary metabolite formed from the catechol--easily undergo auto-oxidation into a free radical at pH greater than or equal to 7.4. By elevation of the pH from 7.4 to 10, an increase in the production of the free radical was observed, which was accompanied by the formation of products with higher hydrophylicity than the catechol and ortho-quinone, as found by HPLC-analysis. The hyperfine structure of the free radical indicates that it is the semi-quinone radical of VP-16-213. At pH 12.5 a secondary radical is formed from the catechol and the ortho-quinone of VP-16-213 besides the semi-quinone radical. One-electron oxidation of the catechol with horseradish peroxidase/hydrogen peroxide resulted in the formation of the same radical as observed under alkaline conditions and subsequent oxidation to the ortho-quinone. If the ortho-quinone was incubated with NADPH cytochrome P-450 reductase, a free radical was detected by spin-trapping with POBN, but not without spin-trapping. Studies on inactivation of phi X174 DNA by the system ortho-quinone of VP-16-213/NADPH cytochrome P-450 reductase suggest that the semi-quinone radical may play a role in the process of inactivation of DNA.