Tests of data quality, scaling assumptions, and reliability of the Danish SF-36

Nurse-led rehabilitation after gynaecological cancer surgery: preliminary results from a clinically controlled, prospective questionnaire study

INTRODUCTION

This article presents the preliminary results and experiences from an ongoing study aiming to develop and test a nurse-led multidisciplinary rehabilitation programme for women who undergo surgery for localised gynaecological cancers and evaluate the effect of the programme prospectively on self-assessed health and coping.

DISCUSSION

Preliminary results have shown that the programme has improved the participant's coping skills, physical well-being and energy level. The programme is easily established and cost-effective. Final results will be available from 2011.

Quality of life after cytoreductive surgery plus early intraperitoneal postoperative chemotherapy for pseudomyxoma peritonei: a prospective study

PURPOSE

The modern treatment of pseudomyxoma peritonei is cytoreductive surgery plus intraperitoneal chemotherapy resulting in a survival of up to 70 percent after 20 years. The goal of this study was to investigate the impact on quality of life of this very aggressive treatment, which has not been done before.

METHODS

Twenty-three prospective patients underwent cytoreductive surgery and early postoperative intraperitoneal chemotherapy for pseudomyxoma peritonei. Patients were followed in clinic 3, 6, 12, 18, and 24 months after surgery and had CT scan of the abdomen every 6 months. Quality of life was prospectively assessed with the generic quality of life instrument Short Form-36 Questionnaire, together with the two symptom-specific instruments--European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, and Colorectal Cancer Module 38--before surgery and at every postoperative visit.

RESULTS

Complete cytoreduction was achieved in 21 patients. No patients died within 30 days. Seventy percent of patients had one or more complications during or after surgery, but all had recovered. Fourteen percent had an asymptomatic recurrence detected within two years. The impact on quality of life of the disease and of its treatment was very modest despite the high morbidity after the treatment. There was a significant decrease in the scores on the Short Form-36 Questionnaire scales of physical dimension and role physical three months after surgery, only returning to normal after another three months. The other scores corresponded to the scores in a normal population.

CONCLUSIONS

Cytoreductive surgery plus early postoperative intraperitoneal chemotherapy is an extensive treatment with a high morbidity but with relatively little impact on quality of life in patients with pseudomyxoma peritonei.

Acute stress response and recovery after whiplash injuries. A one-year prospective study

Chronic whiplash-associated disorder (WAD) represents a major medical and psycho-social problem. The typical symptomatology presented in WAD is to some extent similar to symptoms of post traumatic stress disorder. In this study we examined if the acute stress reaction following a whiplash injury predicted long-term sequelae. Participants with acute whiplash-associated symptoms after a motor vehicle accident were recruited from emergency units and general practitioners. The predictor variable was the sum score of the impact of event scale (IES) completed within 10 days after the accident. The main outcome-measures were neck pain and headache, neck disability, general health, and working ability one year after the accident. A total of 737 participants were included and completed the IES, and 668 (91%) participated in the 1-year follow-up. A baseline IES-score denoting a moderate to severe stress response was obtained by 13% of the participants. This was associated with increased risk of considerable persistent pain (OR=3.3; 1.8-5.9), neck disability (OR=3.2; 1.7-6.0), reduced working ability (OR=2.8; 1.6-4.9), and lowered self-reported general health one year after the accident. These associations were modified by baseline neck pain intensity. It was not possible to distinguish between participants who recovered and those who did not by means of the IES (AUC=0.6). In conclusion, the association between the acute stress reaction and persistent WAD suggests that post traumatic stress reaction may be important to consider in the early management of whiplash injury. However, the emotional response did not predict chronicity in individuals.

Are altered smooth pursuit eye movements related to chronic pain and disability following whiplash injuries? A prospective trial with one-year follow-up

Objective: To evaluate the ability of early smooth pursuit testing to predict chronic whiplash-associated disorders, and to study whether the presence of abnormal smooth pursuit eye movements at one-year follow-up is associated with symptoms at that time.

Design: Prospective cohort study with one-year follow-up.

Setting: The study was carried out at a university research centre and participants were recruited from emergency units and general practitioners.

Subjects: In all, 262 participants were recruited within 10 days from a whiplash injury.

Main measures: Smooth pursuit eye movements were tested with electrooculography (EOG) an average of 12 days after a whiplash trauma and again after one year. Analyses of EOG recordings were computerized. Associations between test results both from baseline and one-year tests and self-reported neck pain, headache, neck disability and working ability one year after the car collision were determined.

Results: Results of early eye movement tests were not associated with the prognosis. Reduced smooth pursuit performance when tested in static cervical rotation at the one-year follow-up was significantly associated with higher neck pain intensity at that time (regression coefficient 0.8, 95% confidence interval (CI) 0.04—1.5), but the association was too weak for the test to discriminate between recovered participants and those with lasting symptoms.

Conclusions: Although reduced smooth pursuit performance at one-year follow-up was associated with persistent neck pain, smooth pursuit eye movement tests are not useful as predictive or diagnostic tests in whiplash-associated disorders.

Diagnosis and treatment of musculoskeletal chest pain: design of a multi-purpose trial

Background

Acute chest pain is a major health problem all over the western world. Active approaches are directed towards diagnosis and treatment of potentially life threatening conditions, especially acute coronary syndrome/ischemic heart disease. However, according to the literature, chest pain may also be due to a variety of extra-cardiac disorders including dysfunction of muscles and joints of the chest wall or the cervical and thoracic part of the spine. The diagnostic approaches and treatment options for this group of patients are scarce and formal clinical studies addressing the effect of various treatments are lacking.

Methods/Design

We present an ongoing trial on the potential usefulness of chiropractic diagnosis and treatment in patients dismissed from an acute chest pain clinic without a diagnosis of acute coronary syndrome. The aims are to determine the proportion of patients in whom chest pain may be of musculoskeletal rather than cardiac origin and to investigate the decision process of a chiropractor in diagnosing these patients; further, to examine whether chiropractic treatment can reduce pain and improve physical function when compared to advice directed towards promoting self-management, and, finally, to estimate the cost-effectiveness of these procedures. This study will include 300 patients discharged from a university hospital acute chest pain clinic without a diagnosis of acute coronary syndrome or any other obvious cardiac or non-cardiac disease. After completion of the clinic's standard cardiovascular diagnostic procedures, trial patients will be examined according to a standardized protocol including a) a self-report questionnaire; b) a semi-structured interview; c) a general health examination; and d) a specific manual examination of the muscles and joints of the neck, thoracic spine, and thorax in order to determine whether the pain is likely to be of musculoskeletal origin. To describe the patients status with regards to ischemic heart disease, and to compare and indirectly validate the musculoskeletal diagnosis, myocardial perfusion scintigraphy is performed in all patients 2–4 weeks following discharge. Descriptive statistics including parametric and non-parametric methods will be applied in order to compare patients with and without musculoskeletal chest pain in relation to their scintigraphic findings. The decision making process of the chiropractor will be elucidated and reconstructed using the CART method. Out of the 300 patients 120 intended patients with suspected musculoskeletal chest pain will be randomized into one of two groups: a) a course of chiropractic treatment (therapy group) of up to ten treatment sessions focusing on high velocity, low amplitude manipulation of the cervical and thoracic spine, mobilisation, and soft tissue techniques. b) Advice promoting self-management and individual instructions focusing on posture and muscle stretch (advice group). Outcome measures are pain, physical function, overall health, self-perceived treatment effect, and cost-effectiveness.

Discussion

This study may potentially demonstrate that a chiropractor is able to identify a subset of patients suffering from chest pain predominantly of musculoskeletal origin among patients discharged from an acute chest pain clinic with no apparent cardiac condition. Furthermore knowledge about the benefits of manual treatment of patients with musculoskeletal chest pain will inform clinical decision and policy development in relation to clinical practice.

Trial registration

NCT00462241 and NCT00373828

Diabetic patients treated with dialysis: complications and quality of life

AIMS/HYPOTHESIS

The aim of this study was to describe the prevalence of complications, health-related quality of life (HRQOL) and the influence of beliefs about control over health in diabetic dialysis patients.

METHODS

Of 53 eligible diabetic patients on chronic dialysis during January 2004 in our clinic, 38 (76%) completed a kidney-specific (Kidney Disease Quality of Life) and a generic (SF-36) questionnaire and were characterised in terms of cardiovascular diseases and diabetic complications. Matched groups of non-diabetic dialysis patients (n = 40) and diabetic patients with a long duration of diabetes and normal kidney function (n = 38) served as controls. Generic HRQOL was compared with matched data from a survey on the Danish general population (n = 2248).

RESULTS

Micro- and macrovascular complications were significantly more frequent in diabetic dialysis patients than in diabetic patients without renal disease. Self-rated physical health was significantly worse (p < 0.01) in diabetic dialysis patients (35 +/- 9 [mean +/- SD]) compared with non-diabetic dialysis patients (41 +/- 10), diabetic patients with normal kidney function (45 +/- 12) and the matched general population (47 +/- 19). The diabetic dialysis patients had similar levels of kidney-specific quality of life and mental health compared with the control groups. Reduced physical health was predicted by the presence of end-stage renal disease, diabetes and short time spent in education. Among the diabetic patients, those who believed more on their own ability to control their diabetes and less on chance reported better mental health and were less likely to be on dialysis.

CONCLUSIONS/INTERPRETATIONS

Diabetic dialysis patients are characterised by a high prevalence of diabetic complications, reduced self-rated physical health but relatively good mental health.

Effect of darbepoetin alfa on physical function in patients undergoing surgery for colorectal cancer. A randomized, double-blind, placebo-controlled study

OBJECTIVE

To study whether perioperative treatment with darbepoetin alfa (DA) improves physical performance following colorectal cancer surgery.

METHODS

Patients admitted for planned colorectal cancer surgery were randomized to receive either weekly placebo or DA 300 or 150 microg depending on the hemoglobin (Hb) concentration. Patients were assessed 10 days before, as well as 7 and 30 days after surgery for work capacity, postural sway, muscle strength, fatigue and quality of life (QoL). The primary outcome measure were the changes in patients' physical performance from preoperative to postoperative day 7.

RESULTS

Of 221 included patients, 151 were evaluable. Baseline characteristics were similar in the 2 groups. Patients receiving DA had a significantly better working capacity on day 7 (p = 0.03) and day 30 (p = 0.03) compared with the placebo group. There were no statistically significant differences between the 2 groups on days 7 or 30 for fatigue, postural sway and QoL. DA treatment significantly (p < 0.01) reduced the decrease in Hb concentrations on day 7 and resulted in an earlier return (p < 0.01) to the preoperative Hb concentration compared to placebo treatment.

CONCLUSION

Perioperative DA treatment improved postoperative work capacity and Hb concentrations, but had no effect on postoperative fatigue, postural sway, QoL and muscle strength.

Improving motivation and goal setting for return to work in a population on sick leave: a controlled study

AIM

Limited knowledge precludes evidence-based interventions targeting return to work among employees on sick leave. The objective of this study was to examine the vocational effect of an intervention focused on motivation, goal setting, and planning of return to work.

DESIGN AND METHODS

A total of 2,795 people, across 6 municipalities, on sick leave for at least 21 days received a questionnaire; 1,256 with a self-assessed poor prognosis for fast return to work were eligible for the study. An examination by a specialist in social medicine, followed by additional counselling by a social worker, was offered to 510 residents in two municipalities and accepted by 264 (52%). The goal was to enhance motivation, goal setting, and planning of return to work. Residents in the remaining municipalities (n=746) received the standard case management offered by the municipalities; 845 (67%) persons completed a follow-up questionnaire gathering data on general health and employment status. The duration of the sick leave was analysed by Cox regression, and the chance of being gainfully employed was analysed by logistic regression analysis, both adjusted for several covariates.

RESULTS

The intervention neither shortened sick leave periods nor increased the likelihood of gainful employment after one year (OR 0.76; 95% CI 0.45-1.28).

CONCLUSIONS

A low-cost counselling programme addressing motivation, goal setting, and planning of return to work did not improve vocational outcomes or reduce the duration of sick leave.

Neck collar, "act-as-usual" or active mobilization for whiplash injury? A randomized parallel-group trial

STUDY DESIGN

Randomized, parallel-group trial.

OBJECTIVE

To compare the effect of 3 early intervention strategies following whiplash injury.

SUMMARY OF BACKGROUND DATA

Long-lasting pain and disability, known as chronic whiplash-associated disorder (WAD), may develop after a forced flexion-extension trauma to the cervical spine. It is unclear whether this, in some cases disabling, condition can be prevented by early intervention. Active interventions have been recommended but have not been compared with information only.

METHODS

Participants were recruited from emergency units and general practitioners within 10 days after a whiplash injury and randomized to: 1) immobilization of the cervical spine in a rigid collar followed by active mobilization, 2) advice to "act-as-usual," or 3) an active mobilization program (Mechanical Diagnosis and Therapy). Follow-up was carried out after 3, 6, and 12 months postinjury. Treatment effect was measured in terms of headache and neck pain intensity (0-10), disability, and work capability.

RESULTS

A total of 458 participants were included. At the 1-year follow-up, 48% of participants reported considerable neck pain, 53% disability, and 14% were still sick listed at 1 year follow-up. No significant differences were observed between the 3 interventions group.

CONCLUSION

Immobilization, "act-as-usual," and mobilization had similar effects regarding prevention of pain, disability, and work capability 1 year after a whiplash injury.

The SF36 Version 2: critical analyses of population weights, scoring algorithms and population norms

BACKGROUND

The SF36 Version 2 (SF36V2) is a revision of the SF36 Version 1, and is a widely used health status measure. It is important that guidelines for interpreting scores are available.

METHOD

A population sample of Australians (n = 3015) weighted to achieve representativeness was administered the SF36V2. Comparisons between published US weights and sample derived weights were made, and Australian population norms computed and presented.

MAJOR FINDINGS

Significant differences were observed on 7/8 scales and on the mental health summary scale. Possible causes of these findings may include different sampling and data collection procedures, demographic characteristics, differences in data collection time (1998 vs. 2004), differences in health status or differences in cultural perception of the meaning of health. Australian population norms by age cohort, gender and health status are reported by T-score as recommended by the instrument developers. Additionally, the proportions of cases within T-score deciles are presented and show there are important data distribution issues.

PRINCIPAL CONCLUSIONS

The procedures reported here may be used by other researchers where local effects are suspected. The population norms presented may be of interest. There are statistical artefacts associated with T-scores that have implications for how SF36V2 data are analysed and interpreted.

Depressive symptoms and the risk of long-term sickness absence: a prospective study among 4747 employees in Denmark

BACKGROUND

The aim of this paper is to examine the impact of depressive symptoms on long-term sickness absence in a representative sample of the Danish workforce.

METHODS

This prospective study is based on 4,747 male and female employees, participating in the Danish Work Environment Cohort Study. Depressive symptoms were measured at baseline. Data on sickness absence were obtained from a national register on social transfer payments. Onset of long-term sickness absence was followed up for 78 weeks.

RESULTS

The cumulative 78 weeks incidence for the onset of long-term sickness absence was 6.5% in men and 8.9% in women. Both men and women with severe depressive symptoms (<or=52 points) were at increased risk of long-term sickness absence during follow-up (men: HR=2.69; 95% CI: 1.18, 6.12; women: HR=2.27; 95% CI: 1.25, 4.11), after adjustment for demographic, health related, and lifestyle factors. When we divided the depressive symptom scores into quartiles, we found no significant effects with regard to long-term sickness absence.

CONCLUSIONS

Severe depressive symptoms, as measured with the MHI-5, increased the risk of future long-term sickness absence in the general Danish working population. However, effects were not linear, but occurred mostly only in those employees with high levels of depressive symptoms.

Responsiveness and minimal clinically important difference for pain and disability instruments in low back pain patients

Background

The choice of an evaluative instrument has been hampered by the lack of head-to-head comparisons of responsiveness and the minimal clinically important difference (MCID) in subpopulations of low back pain (LBP). The objective of this study was to concurrently compare responsiveness and MCID for commonly used pain scales and functional instruments in four subpopulations of LBP patients.

Methods

The Danish versions of the Oswestry Disability Index (ODI), the 23-item Roland Morris Disability Questionnaire (RMQ), the physical function and bodily pain subscales of the SF36, the Low Back Pain Rating Scale (LBPRS) and a numerical rating scale for pain (0–10) were completed by 191 patients from the primary and secondary sectors of the Danish health care system. Clinical change was estimated using a 7-point transition question and a numeric rating scale for importance. Responsiveness was operationalised using standardardised response mean (SRM), area under the receiver operating characteristic curve (ROC), and cut-point analysis. Subpopulation analyses were carried out on primary and secondary sector patients with LBP only or leg pain +/- LBP.

Results

RMQ was the most responsive instrument in primary and secondary sector patients with LBP only (SRM = 0.5–1.4; ROC = 0.75–0.94) whereas ODI and RMQ showed almost similar responsiveness in primary and secondary sector patients with leg pain (ODI: SRM = 0.4–0.9; ROC = 0.76–0.89; RMQ: SRM = 0.3–0.9; ROC = 0.72–0.88). In improved patients, the RMQ was more responsive in primary and secondary sector patients and LBP only patients (SRM = 1.3–1.7) while the RMQ and ODI were equally responsive in leg pain patients (SRM = 1.3 and 1.2 respectively). All pain measures demonstrated almost equal responsiveness. The MCID increased with increasing baseline score in primary sector and LBP only patients but was only marginally affected by patient entry point and pain location. The MCID of the percentage change score remained constant for the ODI (51%) and RMQ (38%) specifically and differed in the subpopulations.

Conclusion

RMQ is suitable for measuring change in LBP only patients and both ODI and RMQ are suitable for leg pain patients irrespectively of patient entry point. The MCID is baseline score dependent but only in certain subpopulations. Relative change measured using the ODI and RMQ was not affected by baseline score when patients quantified an important improvement.

Translation and validation of the SF-36 Health Survey for use among Turkish and Moroccan ethnic minority cancer patients in The Netherlands

In this study, the SF-36 Health Survey was translated into two oral Moroccan languages and the existing Turkish version was culturally adapted for use in The Netherlands, and was tested among 79 Moroccan and 90 Turkish cancer patients. There were normal levels of missing item responses but a higher administration time. With minor exceptions, the scale structure of the SF-36 was confirmed and the reliability of the scales met the 0.70 criterion for group comparisons. The questionnaire distinguished clearly between subgroups formed on the basis of performance status and was responsive to change in performance status over time. Some evidence of differential item function (DIF) was found in both ethnic groups. These results support the use of the SF-36 among Turkish and Moroccan cancer patients in The Netherlands. Additional studies are needed to confirm the psychometrics of the questionnaire when used among these ethnic minority groups in other Western European countries.

Development and preliminary validation of a Greek-language outpatient satisfaction questionnaire with principal components and multi-trait analyses

Background

In the recent years there is a growing interest in Greece concerning the measurement of the satisfaction of patients who are visiting the outpatient clinics of National Health System (NHS) general acute hospitals. The aim of this study is therefore to develop a patient satisfaction questionnaire and provide its preliminary validation.

Methods

A questionnaire in Greek has been developed by literature review, researchers' on the spot observation and interviews. Pretesting has been followed by telephone surveys in two short-term general NHS hospitals in Macedonia, Greece. A proportional stratified random sample of 285 subjects and a second random sample of 100 outpatients, drawn on March 2004, have been employed for the analysis. These have resulted in scale creation via Principal Components Analysis and psychometric testing for internal consistency, test-retest and interrater reliability as well as construct validity.

Results

Four summated scales have emerged regarding the pure outpatient component of the patients' visits, namely medical examination, hospital environment, comfort and appointment time. Cronbach's alpha coefficients and Pearson, Spearman and intraclass correlations indicate a high degree of scale reliability and validity. Two other scales -lab appointment time and lab experience- capture the apparently distinct yet complementary visitor experience related to the radiographic and laboratory tests. Psychometric tests are equally promising, however, some discriminant validity differences lack statistical significance.

Conclusion

The instrument appears to be reliable and valid regarding the pure outpatient experience, whereas more research employing larger samples is required in order to establish the apparent psychometric properties of the complementary radiographic and laboratory-testing process, which is only relevant to about 25% of the subjects analysed here.

Mental distress in the Danish general population

OBJECTIVE

To present data on mental distress in the Danish general population using recently validated Hopkins symptom checklist (SCL) subscales and compare with data from other countries. To evaluate associations between mental distress and biopsychosocial factors.

METHOD

Questionnaires were sent to a gender- and age-stratified random sample comprising 2040 Danes. Mean SCL subscale scores were calculated. Cases were defined in accordance with the traditional criteria, and Danish and US raw score cut-offs were compared. A multiple regression model was developed to describe associations between biopsychosocial factors and SCL scores.

RESULTS

The response rate was 58%. The Danish mean scores were significantly higher than reported for a US non-patient sample, and Danish raw score cut-offs for caseness were higher. The Danish scores were closer to Nordic mean scores. Age, gender, social status, somatic disorder and traumatic life events in the past year in work life as well as personal life were significantly associated with the level of mental distress. SCL scores were compared with scores on the Major Depression Inventory.

CONCLUSION

The SCL mean scores of the Danish general population were relatively high, but similar to data from the Nordic countries. Consequently, interpretation of the Danish SCL requires Danish norms and Danish cut-off scores for caseness.

Danish version of the Oswestry disability index for patients with low back pain. Part 2: Sensitivity, specificity and clinically significant improvement in two low back pain populations

In studies evaluating the efficacy of clinical interventions, it is of paramount importance that the functional outcome measures are responsive to clinically relevant change. Knowledge thereof is in fact essential for the choice of instrument in clinical trials and for clinical decision-making. This article endeavours to investigate the sensitivity, specificity and clinically significant improvement (responsiveness) of the Danish version of the Oswestry disability index (ODI) in two back pain populations. Two hundred and thirty three patients with low back pain (LBP) and/or leg pain completed a questionnaire booklet at baseline and 8 weeks follow-up. Half of the patients were seen in the primary (PrS) and half in the secondary sectors (SeS) of the Danish Health Care System. The booklet contained the Danish version of the ODI, along with the Roland Morris Questionnaire, the LBP Rating Scale, the SF36 (physical function and bodily pain scales) and a global pain rating. At follow-up, a 7-point transition question (TQ) of patient perceived change and a numeric rating scale relating to the importance of the change were included. Responsiveness was operationalised using three strategies: change scores, standardised response means (SRM) and receiver operating characteristic (ROC) analyses. All methods revealed acceptable responsiveness of the ODI in the two patient populations which was comparable to the external instruments. SRM of the ODI change scores at 2 months follow-up was 1.0 for PrS patients and 0.3 for SeS (raw and percentage). A minimum clinically important change (MCID) from baseline score was established at 9 points (71%) for PrS patients and 8 points (27%) for SeS patients using ROC analyses. This was dependable on the baseline entry score with the MCID increasing with 5 points for every 10 points increase in the baseline score. We conclude that the Danish version of the ODI has comparable responsiveness to other commonly used functional status measures and is appropriate for use in low back pain patients receiving conservative care in both the primary and secondary sector.

Danish version of the Oswestry Disability Index for patients with low back pain. Part 1: Cross-cultural adaptation, reliability and validity in two different populations

Over the past 10 years, a plethora of back-specific patient-orientated outcome measures have appeared in the literature. Standardisation has been advocated by an expert panel of researchers proposing a core set of instruments. Of the condition-specific questionnaires the Oswestry Disability Index (ODI) is recommended for use with low back pain (LBP) patients. To date, no Danish version of the ODI exists which has been cross-culturally adapted, validated and published in the peer-reviewed literature. A cross-cultural adaptation and validation of the ODI for the Danish language was carried out according to established guidelines: 233 patients [half of the patients were seen in the primary sector (PrS) and half in the secondary sector (SeS) of the Danish health care system] with LBP and/or leg pain completed a questionnaire booklet at baseline, 1 day or 1 week and 8 weeks follow-up. The booklet contained the Danish version of the ODI, along with the Roland Morris Disability Questionnaire, the LBP Rating Scale, the SF36 (physical function and bodily pain scales) and a global pain rating. For the ODI test-retest analysis (93 stable patients) resulted in an intraclass correlation coefficient of 0.91, a mean difference of 0.8 and 95% limits of agreements of - 11.5 to + 13. Thus, a worsening greater than 12 points and improvement greater than 13 points can be considered a "real" change above the measurement error. A substantial floor effect was found in PrS patients (14.1%). The ODI showed satisfactory cross-sectional discriminant validity when compared to the external measures. Concurrent validity of the ODI revealed: (a) a 10% and 21% lower ODI score compared to the disability and pain measures, respectively, (b) a poorer differentiation of patient disabilities and (c) an acceptable individual ODI score level compared to the external measures. Longitudinal external construct validity showed moderate correlations (range 0.56-0.78). We conclude that the Danish version of the ODI is both a valid and reliable outcome instrument in two LBP patient populations. The ODI is probably most appropriate for use in SeS patients.

Psychosocial work environment and incidence of severe depressive symptoms: prospective findings from a 5-year follow-up of the Danish work environment cohort study

The authors analyzed the impact of psychosocial work characteristics on the incidence of severe depressive symptoms among 4,133 (49% women) employees from a representative sample of the Danish workforce between 1995 and 2000. Psychosocial work characteristics at baseline included quantitative demands, influence at work, possibilities for development, social support from supervisors and coworkers, and job insecurity. Severe depressive symptoms were measured with the five-item Mental Health Inventory of the 36-item Short-Form Health Survey, with a cutoff point of 52. Women with low influence at work (relative risk (RR) = 2.17, 95% confidence interval (CI): 1.23, 3.82) and low supervisor support (RR = 2.03, 95% CI: 1.20, 3.43) were at increased risk for severe depressive symptoms after exclusion of cases at baseline and adjustment for sociodemographic factors, baseline depression score, and health behaviors. Further adjustments for socioeconomic position did not change the result substantially. Additional analyses showed that a one-standard deviation increase on the influence scale resulted in a 27% decreased risk of severe depressive symptoms. Among men, job insecurity predicted severe depressive symptoms (RR = 2.04, 95% CI: 1.02, 4.07). The findings indicate that the work environment influences the risk of developing severe depressive symptoms and that different factors play a role for men and women.

Severity of self-reported diseases and symptoms in Denmark

Objective

To estimate and rank the relative severity of self-reported diseases and symptoms in Denmark.

Method

The 1994 Danish Health and Morbidity Survey collected data from 5,472 Danes older than 16 years of age. Interviews (response frequency: 79%) gave information on diseases and symptoms; a self-administered SF-36 questionnaire (response frequency: 64%) provided information on health-related quality of life. The severity of diseases and symptoms was represented by the health-related quality of life scores that individuals suffering from particular diseases and symptoms obtained on the single dimensions of the SF-36 and on a combined sum of all dimensions. We applied logistic regression to control for the influence of sex, age and socio-economic status on the SF-36 score. We also analysed the interaction between socio-economic status and diseases on the SF-36 score.

Results

Females, more frequently than males, reported on all symptoms and all disease groups except injuries. People with relatively low levels of education reported most diseases, especially musculoskeletal and cardiovascular diseases, more frequently than people with higher education. Age-adjusted mean SF-36 scores for all dimensions combined showed that the symptoms of melancholy/depression and breathing difficulties, psychiatric disorders and respiratory diseases scored lowest (i.e. were most often associated with worse health). Females had lower SF-36 combined scores (worse health) than males on all symptoms. We found interaction between socio-economic status and respiratory diseases and musculoskeletal diseases on the SF-36 score. SF-36 scores also indicated significantly worse health among Danes with low education and income levels compared to those with higher education and income.

Conclusion

In 1994 the Danes most frequently reported musculoskeletal symptoms and diseases. Psychiatric disorders and respiratory diseases were identified as the most severe reported diseases. Due to the interaction between socio-economic status and some diseases, severity estimates should be interpreted with caution or stratified by socio-economic groups.

Psychosocial work environment of hospital workers: validation of a comprehensive assessment scale

BACKGROUND

Studies have shown that adverse workplace factors can increase the risk of ill-health in hospital workers, but more comprehensive measures of the psychosocial work environment are needed.

OBJECTIVES

To test a comprehensive and theory-based psychosocial work environment questionnaire and analyze associations with mental health in a sample of Danish hospital workers.

DESIGN AND PARTICIPANTS

Questionnaire-based cross-sectional study with 343 female employees from a large Danish hospital, including patient care workers (nurses, nurse assistants, midwives) and laboratory technicians.

METHODS

The psychosocial work environment was measured with 14 scales from the Copenhagen psychosocial questionnaire, version I, covering three main areas: demands at work, work organization and interpersonal relations at work. We further measured self-rated mental health and sociodemographic and employment characteristics of the participants. Cronbach's alphas, analyses of covariance, one-sample t-tests, partial correlations and linear regression models were used to analyze data.

RESULTS

Of the 14 work psychosocial workplace scales 12 showed a satisfactory internal consistency (alpha>0.70). Patient care workers had more quantitative, emotional and cognitive demands (all p-values <0.001), higher work pace (p<0.001) and more role conflicts (p=0.01) than laboratory technicians, but also better work organization, including more influence at work, better possibilities for development and a higher meaning of work (all p-values <0.001). Both patient care workers and laboratory technicians had substantially higher scores on the demand scales and lower scores on the influence at work scale than the general Danish working population. Further analyses showed that high levels of demands at work and low levels of work organization and problematic interpersonal relations at work were associated with lower self-rated mental health.

CONCLUSION

The Copenhagen psychosocial questionnaire is a suitable instrument to measure the psychosocial work environment of hospital workers. The comprehensive assessment of the psychosocial work environment helps tailoring interventions to the specific needs of different occupational groups.

Burnout among employees in human service work: design and baseline findings of the PUMA study

AIM

To present the theoretical framework, design, methods, and baseline findings of the first Danish study on determinants and consequences of burnout, and the impact of workplace interventions in human service work organizations.

METHOD

A 5-year prospective intervention study comprising 2,391 employees from different organizations in the human service sector: social security offices, psychiatric prison, institutions for severely disabled, hospitals, and homecare services. Data were collected at baseline and at two follow-ups. The authors developed a new burnout tool (the Copenhagen Burnout Inventory) covering work-related, client-related, and personal burnout. The study includes potential determinants of burnout (e.g. the psychosocial work environment, social relations outside work, lifestyle factors, and personality aspects) and consequences of burnout (e.g. poor health, low job satisfaction, turnover, and absenteeism). Here, the focus is on the description of the study population at baseline, including associations of work burnout with psychosocial work environment scales and absence.

RESULTS

Response rate at baseline was 80.1%. Midwives and homecare workers had high levels on both work- and client-related burnout. Prison officers had the highest level on client-related burnout. Supervisors and office assistants had low levels on both scales. Work burnout showed the highest correlations with job satisfaction (r = -0.51), quantitative demands (r = 0.48), role-conflicts (r = 0.44), and emotional demands (r = 0.42). Sickness absence was 13.9 vs 6.0 days among participants in the highest and lowest work burnout quartile, respectively.

CONCLUSION

The findings indicate that study design and methods are adequate for the upcoming prospective analyses of aetiology and consequences of burnout and of the impact of workplace interventions.

Determining the basic psychometric properties of the Greek KDQOL-SF

The aim of this study was to determine the basic psychometric properties, i.e. reliability and validity, of the Greek version of the Kidney Disease Quality of Life Short Form (KDQOL-SF). The instrument was self-administered to a homogenous group of 665 end stage renal disease patients in 20 dialysis units throughout Greece and the overall response rate was 72.6%. Reliability was demonstrated by Cronbach's alpha exceeding the recommended minimum value of 0.70 in all, except one, scales. Tests of item-internal consistency, after correction for overlap, resulted in correlations between items and their hypothesized scales, which exceeded the 0.40 standard in 94.5% of the cases. Item discriminant validity tests indicated 100% scaling success for six out of eight generic and disease-targeted scales. Validity was supported by the confirmation of expected correlations between scales and the overall health-rating item included in the instrument and with sociodemographic and self-reported health variables. Multiple stepwise linear regression analysis demonstrated that all disease-targeted scales were important predictors of SF-36 general health scales and the variance explained ranged from 37% to 57%. Overall, the psychometric properties of the KDQOL-SF, resulting from this first-time administration of the instrument to a Greek dialysis population, were good and the disease targeted scales were informative and of high internal consistency reliability. Cross-sectional construct validity is demonstrated, despite the lack of external validity criteria based on clinical ratings of severity. The results support administering the Greek KDQOL-SF in studies evaluating dialysis therapy and contribute to transnational comparison of findings.

Is sense of coherence a mediator or moderator of relationships between violence at work and stress reactions?

The relationships between exposure to violence at work, sense of coherence, and stress reactions were analysed in a large sample of the Danish workforce. The results showed that employees subjected to violence have a weaker sense of coherence than the rest of the respondents. Sense of coherence acted as a mediator and not as a moderator of relationships between exposure to violence and psychological, psychosomatic and cognitive stress reactions. The stability of the sense of coherence construct is discussed. With respect to the relation between sense of coherence and violence, preventative measures at the individual and organizational level are suggested.

A 5-year follow-up study of aggression at work and psychological health

In a longitudinal cohort study, organizational climate and long-term effects of exposure to nasty teasing (aggression) at work were investigated. The baseline consisted of a representative sample of Danish employees in 1995 with a response rate of 80% (N = 5,652). Of these, 4,647 participated in the follow-up in 2000 (response rate 84%). In 1995, 6.3% were subjected to nasty teasing with no significant gender difference. At baseline, we found significant associations among nasty teasing, a negative organizational climate, and psychological health effects. In the follow-up analyses, associations were found between exposure to nasty teasing at baseline and psychological health problems at follow-up, even when controlled for organizational climate and psychological health at baseline and nasty teasing at follow-up. Stratified for gender, the follow-up associations were significant for women but not for men. Low coworker support and conflicts at baseline and teasing at follow-up mediated the effects on men.

Are factor analytical techniques used appropriately in the validation of health status questionnaires? A systematic review on the quality of factor analysis of the SF-36

Factor analysis is widely used to evaluate whether questionnaire items can be grouped into clusters representing different dimensions of the construct under study. This review focuses on the appropriate use of factor analysis. The Medical Outcomes Study Short Form-36 (SF-36) is used as an example. Articles were systematically searched and assessed according to a number of criteria for appropriate use and reporting. Twenty-eight studies were identified: exploratory factor analysis was performed in 22 studies, confirmatory factor analysis was performed in five studies and in one study both were performed. Substantial shortcomings were found in the reporting and justification of the methods applied. In 15 of the 23 studies in which exploratory factor analysis was performed, confirmatory factor analysis would have been more appropriate. Cross-validation was rarely performed. Presentation of the results and conclusions was often incomplete. Some of our results are specific for the SF-36, but the finding that both the application and the reporting of factor analysis leaves much room for improvement probably applies to other health status questionnaires as well. Optimal reporting and justification of methods is crucial for correct interpretation of the results and verification of the conclusions. Our list of criteria may be useful for journal editors, reviewers and researchers who have to assess publications in which factor analysis is applied.

The effect of a multidimensional exercise intervention on physical capacity, well-being and quality of life in cancer patients undergoing chemotherapy

The aim of the present study was to investigate the impact of a multidimensional exercise intervention focusing on physical capacity; one-repetition maximum (1RM) and maximum oxygen uptake (VO2Max), activity level, general well-being and quality of life in cancer patients undergoing chemotherapy. The intervention comprised resistance and fitness training, massage, relaxation and body-awareness training. Eighty-two cancer patients, with or without evidence of residual disease, were included: 66 patients with 13 different types of solid tumours and 16 patients with 6 types of haematological malignancies. The patients trained in mixed groups for 9 h weekly for 6 weeks. Physical capacity, physical activity level and psychosocial well-being as measured by the Medical Outcomes Study 36-item Short-Form Health Survey and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 were assessed pre- and post-intervention. Highly significant increases were achieved in muscular strength (p<0.001), physical fitness (p<0.001) and physical activity levels (p<0.001). The patients reported significant reduction in treatment-related symptoms, i.e., fatigue (p=0.006) and pain (p=0.03). Highly significant improvements were observed in physical functioning (p<0.001) and role functioning (p<0.001). Even patients with advanced disease were able to improve their results after 6 weeks. It is concluded that a multidimensional exercise intervention, including resistance training, may be beneficial for cancer patients undergoing chemotherapy. This study indicates significant clinical meaningful improvements. The exact role of the intervention has to be defined in a randomized controlled design. A clinically controlled trial including 250 patients is currently being carried out.

Occupational disorders and return to work: a randomized controlled study

OBJECTIVE

Goal setting and motivational factors are strongly associated with maintaining a job and return to work after sick leave, but research into the effects of interventions targeting these factors is limited. We conducted a randomized controlled study to examine the vocational effect of intervention focusing on motivation, goal setting and planning for return to work.

DESIGN AND METHODS

Of 243 patients at risk of long-term sick leave or job dropout, 184 (76%) provided complete baseline information for the study. After randomization to an intervention group (n=92) and a reference group (n=92), occupational physicians examined the participants in accordance with standard guidelines. The intervention group received additional support from a social worker in order to enhance goal setting, motivation and planning for return to work. After 1 year 163 participants (89%) provided data on general health and employment status. The risk of not being gainfully employed was analysed by logistic regression analysis with adjustment for several covariates.

RESULTS

The intervention did not increase the likelihood of gainful employment after 1 year or reduce the average number of days of sick leave.

CONCLUSION

A low-cost counselling program addressing motivation, goal setting and planning for return to work did not improve vocational outcomes or reduce sick leave among patients with work-related disorders.

Validating and norming of the Greek SF-36 Health Survey

The main objective of this study was to validate the Greek SF-36 Health Survey and to provide general population normative data. The survey was administered to a stratified representative sample (n = 1426) of the general population residing in the broader Athens area and the response rate was 70.6%. Statistical analysis, according to documented procedures developed within the IQOLA Project, was performed. The missing value rate was very low, ranging from 0.1 to 1.3% at the item level. Multitrait scaling analysis confirmed the hypothesized scale structure of the SF-36. Cronbach's alpha coefficient met the criterion (>0.70) for group analysis in all eight scales. Known group comparisons yielded consistent support of construct validity of the SF-36. Significant statistical differences in mean scores were observed in relation to demographic and social characteristics such as gender, age, education and marital status.

Physical, mental and social factors associated with frequent attendance in Danish general practice. A population-based cross-sectional study

Knowledge of which factors are prompting patients to seek primary care is important to the ongoing effort to improve management in general, and management of frequent attenders (FAs) in particular. We conducted a cross-sectional population-based study with the aim at examining associations between physical, mental and social factors and frequent attendance in general practice. We collected questionnaire and registry data in the County of Aarhus (630,000 inhabitants), Denmark. Half of the county general practices (132 practices, 220 GPs) were selected randomly. FAs were defined as the top 10% attenders over the past 12 months. A questionnaire including SF-36 and questions about physical and mental health and social conditions was sent to age and gender stratified samples of FAs and non-FAs from these practices. Impairments (SF-36) associated with frequent attendance were physical in 54-71% (prevalence difference (PD): 16-33%, adjusted prevalence ratio (adj. PR): 1.1-1.7), mental in 58-70% (PD: 17-25%, adj. PR:1.1-1.4) and social in 40-59% (PD: 13-28%, adj. PR:0.9-1.5). Among FAs, 46-88% had used three or more different drugs (PD: 26-39%, adj. PR:1.5-2.3) and 27-41% had been referred one or more times to outpatient specialists (PD: 4-19%, adj. PR:1.2-2.5). Although our data cannot determine the direction of causality, they clearly demonstrate that FAs carry a large burden of physical, mental and social impairments which underpins the complexity and heterogeneity of the problems which they present. The results make clear that biopsychosocial management is a core issue in FA management in general practice.

Osteoporosis Health Belief Scale: Minor changes were required after telephone administration among women

OBJECTIVE

The Osteoporosis Health Belief Scale (OHBS) is a 42-item scale designed to measure general health motivation, perceived susceptibility to and seriousness of osteoporosis, and beliefs about calcium intake and exercise in preventing and treating osteoporosis. The purpose of this study was to examine the psychometric properties of the OHBS by telephone administration among older women.

STUDY DESIGN AND SETTING

A convenience sample of 425 women aged 61-93 years participating in a longitudinal arthritis study was recruited by telephone. Item clarity was evaluated and 22 additional items (6 reworded, 16 from other questionnaires) were considered to supplement or replace existing scale items. Multitrait scaling techniques and exploratory factor analysis were used to test scale structure. Construct validity was tested based on theoretical hypothesis between OHBS subscale scores and participant characteristics.

RESULTS

A few modifications to the OHBS scale were suggested, reducing the scale by five items (two redundant, three did not load), rewording one item and moving on item to a different subscale. The modified 37-item OHBS had a seven-factor uncorrelated solution explaining 48% of the model variance with internal consistency ranging from 0.73 to 0.88.

CONCLUSION

Relatively minor changes to the OHBS results in reduced redundancy and improved internal structure of the scale for telephone administration among women over 60 years of age. Further examination is recommended to confirm these findings.

The feasibility of applying item response theory to measures of migraine impact: a re-analysis of three clinical studies

BACKGROUND

Item response theory (IRT) is a powerful framework for analyzing multiitem scales and is central to the implementation of computerized adaptive testing.

OBJECTIVES

To explain the use of IRT to examine measurement properties and to apply IRT to a questionnaire for measuring migraine impact--the Migraine Specific Questionnaire (MSQ).

METHODS

Data from three clinical studies that employed the MSQ-version 1 were analyzed by confirmatory factor analysis for categorical data and by IRT modeling.

RESULTS

Confirmatory factor analyses showed very high correlations between the factors hypothesized by the original test constructions. Further, high item loadings on one common factor suggest that migraine impact may be adequately assessed by only one score. IRT analyses of the MSQ were feasible and provided several suggestions as to how to improve the items and in particular the response choices. Out of 15 items, 13 showed adequate fit to the IRT model. In general, IRT scores were strongly associated with the scores proposed by the original test developers and with the total item sum score. Analysis of response consistency showed that more than 90% of the patients answered consistently according to a unidimensional IRT model. For the remaining patients, scores on the dimension of emotional function were less strongly related to the overall IRT scores that mainly reflected role limitations. Such response patterns can be detected easily using response consistency indices. Analysis of test precision across score levels revealed that the MSQ was most precise at one standard deviation worse than the mean impact level for migraine patients that are not in treatment. Thus, gains in test precision can be achieved by developing items aimed at less severe levels of migraine impact.

CONCLUSIONS

IRT proved useful for analyzing the MSQ. The approach warrants further testing in a more comprehensive item pool for headache impact that would enable computerized adaptive testing.

Feasibility, physical capacity, and health benefits of a multidimensional exercise program for cancer patients undergoing chemotherapy

Cancer patients frequently experience considerable loss of physical capacity and general wellbeing when diagnosed and treated for their disease. The aim of this study was to evaluate the feasibility, physical capacity, and health benefits of a multidimensional exercise program for cancer patients during advanced stages of disease who are undergoing adjuvant or high-dose chemotherapy. The supervised program included high- and low-intensity activities (physical exercise, relaxation, massage, and body-awareness training). A total of 23 patients between 18 and 65 years of age (median 40 years) participated in groups of seven to nine patients for 9 h weekly for 6 weeks. Physical capacity in terms of repetition maximum (RM) and maximal oxygen uptake (VO(2)max), physical activity level and psychosocial wellbeing (EORTC QLQ-C30, SF-36, HAD) were compared prior to and after completion of the program. The program was safe and well tolerated. The completion rate was 85.2%. Highly significant increases in physical capacity (1RM, VO(2)max) and an improved level of physical activity were achieved. Quality of life and general wellbeing assessments indicated improvements in several measures, but without reaching significance. It is concluded that an exercise program, which combines high- and low-intensity physical activities, may be used to prevent and/or minimize physical inactivity, fatigue, muscle wasting and energy loss in cancer patients undergoing chemotherapy.

ACE genotype and physical training effects: a randomized study among elderly Danes

BACKGROUND AND AIMS

The level of physical functioning (PF) late in life has, in recent years, been shown to be influenced by genetic factors. One of the most extensively studied genetic variants associated with PF and trainability is insertion/deletion (I/D) polymorphism in the gene encoding Angiotensin Converting Enzyme (ACE). However, ACE studies have mainly been conducted among younger persons in excellent physical shape. In this study, we examine whether the level of PF, trainability, or rate-of-change are associated with the ACE genotype among the elderly.

METHODS

We used data from 4 randomized training studies of elderly Danes (N = 203). The measures of PF were self-report, maximal oxygen uptake, muscle strength, walking speed, and body composition.

RESULTS

Overall, a favorable change in the measures of PF was observed in training groups compared with control groups. However, within groups, neither pre- or post-training/control period levels of PF nor differences in pre- and post-levels were associated with the ACE genotype.

CONCLUSIONS

On the basis of our randomized studies, we could not detect any association between the ACE genotype and the level of PF or change, regardless of whether response to physical training or spontaneous changes was studied.

Der SF-12 - Das Problem der Missing Data

Zusammenfassung. Der SF-12 stellt die Kurzform der Short Form 36 Health Survey dar. Ein wenig beachteter Nachteil im Algorithmus zur Bildung der Skalenindizes liegt darin, dass die Bildung der Skalenwerte nur dann empfohlen wird, wenn alle Items von einer Person beantwortet wurden. Ist dies nicht der Fall, ist die entsprechende Person nicht mit Werten des SF-12 repräsentiert (Missing Case). Im Rahmen einer Studie zum Wirksamkeitsvergleich in der orthopädischen medizinischen Rehabilitation konnten zu Beginn (t1) und Ende (t2) der Rehabilitationsmaßnahme insgesamt 1176 Patienten erreicht werden. Trotz weitestgehend vollständiger Datensätze kam es zu t1 zu 29% fehlender Fälle im SF-12. Die Verteilungsanalyse dieser Missing Data wies v.a. darauf hin, dass es Personen höheren Alters und geringerer Schulbildung sind, die die Items des SF-12 nicht beantworteten. Insbesondere bei den aufwändig formulierten Items gibt es einen hohen Anteil fehlender Werte. Eine Überarbeitung des Instruments mit dem Ziel der Vereinfachung der Fragestellungen scheint damit erforderlich.

Vitamin B-12 treatment has limited effect on health-related quality of life among individuals with elevated plasma methylmalonic acid: a randomized placebo-controlled study

OBJECTIVE

To examine the hypothesis that treatment with vitamin B-12 improves health-related quality of life (HRQOL) in individuals with biochemical signs of vitamin B-12 deficiency.

DESIGN

A randomized placebo-controlled study.

SETTING

Municipality of Aarhus, Denmark.

SUBJECTS

Nonhospitalized individuals (n = 140) with a modest increase in plasma methylmalonic acid (0.40-2.00 micromol L-1) not previously treated with vitamin B-12.

INTERVENTION

The participants were randomized to vitamin B-12 injection treatment or placebo weekly for 4 weeks and re-examined 3 months later. The investigator and the participants were blinded to the intervention.

MAIN OUTCOME MEASURE

Change in HRQOL assessed by the SF-36 questionnaire from baseline to follow-up examination 3 months later.

RESULTS

The participants reported a significantly worser HRQOL than the age- and sex-matched Danish general population (P < 0.001). However, no change was observed after treatment with vitamin B-12 for seven of eight health dimensions. A significant improvement was found only in general health when compared with the placebo group (P = 0.03).

CONCLUSIONS

Vitamin B-12 treatment influenced only one of eight dimensions of HRQOL amongst participants with biochemical signs of vitamin B-12 deficiency. We therefore question the benefit of vitamin B-12 treatment amongst elderly with a modestly increased plasma methylmalonic acid as the only sign of vitamin B-12 deficiency.

Measuring well-being rather than the absence of distress symptoms: a comparison of the SF-36 Mental Health subscale and the WHO-Five Well-Being Scale

The health status questionnaire Short-Form 36 (SF-36) includes subscales measuring both physical health and mental health. Psychometrically, the mental health subscale contains a mixture of mental symptoms and psychological well-being items, among other things, to prevent a ceiling effect when used in general population studies. Three of the mental health well-being items are also included in the WHO-Five well-being scale. In a Danish general population study, the mental health subscale was compared psychometrically with the WHO-Five in order to evaluate the ceiling effect. Tests for unidimensionality were used in the psychometric analyses, and the sensitivity of the scales in differentiating between changes in self-reported health over the past year has been tested. The results of the study on 9,542 respondents showed that, although the WHO-Five and the mental health subscale were found to be unidimensional, the WHO-Five had a significantly lower ceiling effect than the mental health subscale. The analysis identified the three depression symptoms in the mental health subscale as responsible for the ceiling effect. The WHO-Five was also found to be significantly superior to the mental health subscale in terms of its sensitivity in differentiating between those persons whose health had deteriorated over the past year and those whose health had not. In conclusion, the WHO-Five, which measures psychological well-being, reflects aspects other than just the absence of depressive symptoms.

Psychometric properties of the RAND-36 among three chronic diseases (multiple sclerosis, rheumatic diseases and COPD) in The Netherlands

OBJECTIVE

In this article, psychometric properties both of the total RAND-36 and of its subscales, such as unidimensionality, differential item functioning (DIF or item bias), homogeneity and reliabilities, are examined.

METHODS

The data from populations with three chronic illnesses, multiple sclerosis (n = 448), rheumatism (n = 336) and COPD (n = 259), have been collected in different parts of the Netherlands. The main technique used was Mokken scale analysis for polytomous items.

RESULTS

All subscales of the RAND-36 appeared to be unidimensional. For the subscales 'mental health' and general health perceptions' some minor indications of DIF for the different chronic illnesses were found. Reliabilities of almost all subscales in all subpopulations were higher than 0.80, while the homogeneities of almost all subscales in all subpopulations were higher than 0.50, indicating 'strong unidimensional, hierarchical scales'.

CONCLUSIONS

In general, the subscales of the RAND-36 can be used to compare persons with different chronic illnesses. The subscale 'general health perceptions' did not function as well as would be preferred.

Health related quality of life after conservative or invasive treatment of inducible postinfarction ischaemia. DANAMI study group

OBJECTIVE

To assess health related quality of life in patients with inducible postinfarction ischaemia.

DESIGN

A questionnaire based follow up study on patients randomised to conservative or invasive treatment because of postinfarction ischaemia.

SETTING

Seven county hospitals in eastern Denmark and the Heart Centre, National University Hospital, Copenhagen, Denmark.

PATIENTS

113 patients with inducible postinfarction ischaemia: 51 were randomised to conservative treatment and 62 to invasive treatment. Average follow up time was three years (19-57 months).

MAIN OUTCOME MEASURES

SF-36, Rose angina and dyspnoea questionnaire, drug use, lifestyle, and cognitive function.

RESULTS

Invasively treated patients scored better on the SF-36 scales of physical functioning (p = 0.03) and on role-physical (p = 0.04) and physical component scales (p = 0.05) and took significantly less anti-ischaemic drug treatment. Angina occurred in 18% of the invasively treated patients and 31% of the conservatively treated patients (p = 0.09). However, more invasively treated patients suffered from concentration difficulties (18% v 4%; p = 0.04).

CONCLUSIONS

Patients who were treated invasively had better health related quality of life scores in the physical variables compared with conservatively treated patients. However, a larger proportion of invasively treated patients had concentration difficulties.

Evaluation of a simple, non-surgical concept for management of urinary incontinence (minimal care) in an open-access, interdisciplinary incontinence clinic

Our objective was to evaluate a new concept for assessment and treatment of urinary incontinence in an open-access, interdisciplinary incontinence clinic. A standardized program for investigation and treatment of incontinence was based on minimal relevant investigations, primarily non-surgical treatment with a limited consumption of resources ("minimal care"). This was a prospective observational study of 408 consecutive women examined and treated in the clinic. The main characteristics of the women were a high median age and a high prevalence of severe concomitant diseases with possible influence on lower urinary tract function. More than half of the patients had urge or mixed incontinence. Most of the patients were managed with conservative treatment. Fifteen percent were referred to in-hospital treatment, with 5% to incontinence surgery. In total 44% felt cured or very much improved. Before and after treatment one third of the women completed quality-of-life questions and voiding charts, while 43% completed the pad tests. Quality of life improved significantly. Objectively leakage on pad test and voiding charts was significantly improved. The patients were in general very satisfied with clinic's program. Almost one fourth of the women were followed up for 6 months after discharge. No significant deterioration in the subjective results were found compared to status at discharge. In conclusion, the results highlight the need for advice and treatment of patients with incontinence. The minimal care program and interdisciplinary structure in the incontinence clinic offer effective and low cost treatment for urinary incontinence. The open-access, interdisciplinary incontinence clinic model is recommended. Neurourol. Urodynam. 18:9-17, 2000.

The Danish SF-36 Health Survey: translation and preliminary validity studies

This article reports on the Danish translation of SF-36 and discusses the procedures used for translation improvement, translation evaluation, and scale evaluation. We followed the standard procedures of the International Quality of Life Assessment (IQOLA) Project including forward and backward translation, independent assessment of translation quality, assessment of response-choice weighting through visual analogue scale (VAS) investigations, and psychometric testing of the translated questionnaire. We found that backward translation, independent quality assessment, and VAS studies provided useful information for translation improvement. The Danish SF-36 received a favorable translation evaluation by independent rating; however, interrater agreement was low. Preliminary validity studies generally supported the internal consistency and homogeneity of the Danish SF-36, and the questionnaire performed satisfactorily in distinguishing depressive patients from nonpatients. On the basis of this and other studies, we recommend use of the Danish SF-36 in research.

Comparison of Rasch and summated rating scales constructed from SF-36 physical functioning items in seven countries: results from the IQOLA Project. International Quality of Life Assessment

Rasch models for polytomous items were used to assess the scaling assumptions and compare item response patterns in the 10-item SF-36 physical functioning scale (PF-10) for general population respondents in Denmark, Germany, Italy, the Netherlands, Sweden, the United Kingdom, and the United States. The Rasch model of physical functioning developed in the United States was compared to models for other countries, and each country was compared to a multinational composite. Strong scale congruence across the seven countries was demonstrated; items that varied between countries and from the composite may reflect unique cultural response patterns or differences in translation. Scoring algorithms based on the Rasch model for each country were superior to the current Likert scoring in tests of relative validity (RV) in discriminating among age groups in all countries. In relation to the Likert PF-10 scoring (RV = 1.00), scores estimated using the Rasch rating scale model achieve a median RV of 1.31 (range: 1.01-1.59), while the Rasch partial credit model attained a median RV of 1.44 (range: 1.01-2.23). Rasch models hold good potential for improving health status measures, estimating individual scores when responses to scale items are missing, and equating scores across countries.

Methods for testing data quality, scaling assumptions, and reliability: the IQOLA Project approach. International Quality of Life Assessment

Following the translation development stage, the second research stage of the IQOLA Project tests the assumptions underlying item scoring and scale construction. This article provides detailed information on the research methods used by the IQOLA Project to evaluate data quality, scaling and scoring assumptions, and the reliability of the SF-36 scales. Tests include evaluation of item and scale-level descriptive statistics; examination of the equality of item-scale correlations, item internal consistency and item discriminant validity; and estimation of scale score reliability using internal consistency and test-retest methods. Results from these tests are used to determine if standard algorithms for the construction and scoring of the eight SF-36 scales can be used in each country and to provide information that can be used in translation improvement.

Differential item functioning in the Danish translation of the SF-36

Statistical analyses of Differential Item Functioning (DIF) can be used for rigorous translation evaluations. DIF techniques test whether each item functions in the same way, irrespective of the country, language, or culture of the respondents. For a given level of health, the score on any item should be independent of nationality. This requirement can be tested through contingency-table methods, which are efficient for analyzing all types of items. We investigated DIF in the Danish translation of the SF-36 Health Survey, using two general population samples (USA, n = 1,506; Denmark, n = 3,950). DIF was identified for 12 out of 35 items. These results agreed with independent ratings of translation quality, but the statistical techniques were more sensitive. When included in scales, the items exhibiting DIF had only a little impact on conclusions about cross-national differences in health in the general population. However, if used as single items, the DIF items could seriously bias results from cross-national comparisons. Also, the DIF items might have larger impact on cross-national comparison of groups with poorer health status. We conclude that analysis of DIF is useful for evaluating questionnaire translations.

Tests of data quality, scaling assumptions, and reliability of the SF-36 in eleven countries: results from the IQOLA Project. International Quality of Life Assessment

Data from general population samples in 11 countries (n = 1483 to 9151) were used to assess data quality and test the assumptions underlying the construction and scoring of multi-item scales from the SF-36 Health Survey. Across all countries, the rate of item-level missing data generally was low, although slightly higher for items printed in the grid format. In each country, item means generally were clustered as hypothesized within scales. Correlations between items and hypothesized scales were greater than 0.40 with one exception, supporting item internal consistency. Items generally correlated significantly higher with their own scale than with competing scales, supporting item discriminant validity. Scales could be constructed for 93-100% of respondents. Internal consistency reliability of the eight SF-36 scales was above 0.70 for all scales, with two exceptions. Floor effects were low for all except the two role functioning scales; ceiling effects were high for both role functioning scales and also were noteworthy for the Physical Functioning, Bodily Pain, and Social Functioning scales in some countries. These results support the construction and scoring of the SF-36 translations in these 11 countries using the method of summated ratings.