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The PROsetta Stone Project, summarized in this issue by Schalet et al. (Psychometrika 86, 2021), is a major step forward in enabling comparability between different patient-reported outcomes measures. Schalet et al. clearly describe the psychometric methods used in the PROsetta Stone project and other projects from the Patient-Reported Outcomes Measurement Information System (PROMIS): linking based on unidimensional item response theory (IRT), equipercentile linking, and calibrated projection based on multidimensional IRT. Analyses in a validation data set and simulation studies provide strong support that the linking methods are robust when basic assumptions are fulfilled. The links already established will be of great value to the field, and the methodology described by Schalet et al. will hopefully inspire the next series of linking studies. Among potential improvements that should be considered by new studies are: (1) a thorough evaluation of the content of the measures to be linked to better guide the evaluation of measurement assumptions, (2) improvements in the design of linking studies such as selection of the optimal sample to provide data in the score ranges where linking precision is most critical and using counterbalanced designs to control for order effects. Finally, it may be useful to consider how the linking algorithms are used in subsequent data analyses. Analytic strategies based on plausible values or latent regression IRT models may be preferable to the simple transformation of scores from one patient at the time.

Objectives Tension-type headache (TTH) is the most prevalent primary headache disorder. We assessed the cross-sectional impact of TTH on health related quality of life (HRQoL) in a general population. We also examined the association of HRQoL scores with headache frequency, disability, medication overuse, poor self-rated health, psychiatric comorbidity, and pain sensitivity in individuals with TTH. Methods A sample of 547 subjects completed a headache diagnostic interview, the SF-12 to calculate physical (PCS) and mental (MCS) health component scores, depression (major depression inventory [MDI]) and neuroticism (Eysenck Personality Questionnaire) measures. We defined the following headache diagnosis categories: pure TTH, pure migraine, and coexistent headache (TTH + migraine). Cases were further classified into chronic (≥15) or episodic ( Results Using generalized linear models (GLM) adjusted for age, sex and education, both PCS-12 and MCS-12 scores varied in groups distinguished by migraine and TTH status; scores were lower for individuals with coexistent headache (TTH + migraine; n=83), followed by pure TTH (n=97) and pure migraine (n=43) compared to the no headache group (n=324) (p≤0.001). In analyses considering chronicity, PCS-12 scores were lower in chronic coexistent headache followed by pure chronic TTH (CTTH), episodic migraine +/− episodic TTH (ETTH) and pure ETTH than in the no headache group (p≤0.001). MCS-12 scores were lower in pure CTTH, followed by chronic coexistent headache, episodic migraine +/− ETTH and pure ETTH compared to the no headache group (p≤0.001). Multiple regression models showed that in TTH, lower PCS-12 scores were associated with age (p=0.04), female sex (p=0.02), and poor self-rated health (p≤0.001). Lower MCS-12 scores in TTH were associated with depression (p≤0.001). Conclusions In a population sample, TTH, and to higher degree CTTH, are associated with decreased HRQoL.

Background In 2013, Denmark implemented a reform that tightened the criteria for disability pension, expanded a subsidized job scheme (‘flexi-job’) and introduced a new vocational rehabilitation scheme. The overall aim of the reform was to keep more persons attached to the labour market. This study investigates the impact of the reform among persons with chronic disease and whether this impact differed across groups defined by labour market affiliation and chronic disease type. Methods The study was conducted as a register-based, nationwide cohort study. The study population included 480 809 persons between 40 and 64 years of age, who suffered from at least one of six chronic diseases. Hazard ratios (HR) and 95% confidence intervals (CI) of being awarded disability pension or flexi-job in the 5 years after vs. the 5 years prior to the reform were estimated. Results Overall, the probability of being awarded disability pension was halved after the reform (HR = 0.49, CI: 0.47–0.50). The impact was largest for persons receiving sickness absence benefits (HR = 0.31, CI: 0.24–0.39) and for persons with functional disorders (HR = 0.38, CI: 0.32–0.44). Also, the impact was larger for persons working in manual jobs than for persons working in non-manual jobs. The probability of being awarded a flexi-job was decreased by one-fourth (HR = 0.76, CI: 0.74–0.79) with the largest impact for high-skilled persons working in non-manual jobs. Conclusion Access to disability pension and flexi-job decreased after the reform. This impact varied according to labour market affiliation and chronic disease type.

Background This survey examined the experiences of people living with schizophrenia who have used oral antipsychotics (APs). Methods Adults with self-reported physician-diagnosed schizophrenia (N=200), who were members of an online research participation panel and reported taking one or more oral APs within the last year, completed a cross-sectional online survey that focused on direct report of their experiences regarding APs (eg, symptoms, side effects, adherence). Descriptive analyses were conducted for the total survey sample and for subgroups defined a priori by experience with specific, prevalent side effects. Results The mean age of the sample was 41.9 (SD=11.0) years, 50% of participants were female, and 32% were nonwhite. Overall ratings were positive for medication effectiveness and convenience but negative for side effects. While most participants reported that APs improved schizophrenia symptoms (92%), 27% reported APs as having done "more harm than good." Almost all participants (98%) reported experiencing side effects of APs, with the most common being anxiety (88%), feeling drowsy/tired (86%), and trouble concentrating (85%). Side effects frequently cited as either "extremely" or "very" bothersome were weight gain (56%), sexual dysfunction (55%), and trouble concentrating (54%). Over 80% reported that side effects had negatively impacted their work and social functioning (eg, social activities or family/romantic relationships). Since initiating treatment, 56% of respondents had stopped taking APs at some point (65% of these due to side effects). Side effects commonly reported as having led to stopping AP treatment were "feeling like a 'zombie'" (22%), feeling drowsy/tired (21%), and weight gain (20%). Conclusion Most participants reported improvements in schizophrenia symptoms associated with the use of APs. However, most participants also reported experiencing numerous bothersome side effects that negatively impacted their work, social functioning, and treatment adherence. Results highlight the unmet need for new APs with favorable benefit-risk profiles.

BackgroundAdaptation of a patient-reported outcomes survey into a new language requires careful translation procedures as well as qualitative and quantitative psychometric testing. This study aimed to evaluate the basic psychometric properties of the new Saudi Arabian SF-36v2 and establish norm data for Saudi Arabia.MethodsTranslation and adaptation of the SF-36v2 used standard methodology. Psychometric validation included two stages: 1) A qualitative study (n = 100) explored the components of health and health-related quality of life considered important in Saudi Arabia and evaluated the content validity of the SF-36v2 in Saudi Arabia, and 2) A quantitative study (n = 6166) evaluated the basic psychometric properties of the Saudi SF-36v2 and established norm data for Saudi Arabia. Comparison with US general population data (n = 4040) evaluated differential item function (DIF) and cross-national differences.ResultsThe qualitative study supported the content validity of the Saudi SF-36v2. Cognitive debriefing identified only few and minor problems. Psychometric analyses supported item convergence within scales and differentiation across scales of the SF-36v2. Scale level exploratory factor analyses did not support the typical distinction between physical health and mental health components. Internal consistency reliability was satisfactory for all scales except the social function scale (alpha = 0.67). Cross-national DIF was identified for 9 items. In the Saudi general population, the average vitality score was lower for women (− 2.71 points) compared to men. For men, older age groups scored lower on the physical function scale (− 3.31) and the physical health component (− 3.06). For women, older age groups scored lower on the role physical (− 3.72), bodily pain (− 3.66), and vitality (− 2.32) scales as well as the physical health component (− 3.52). Compared to the 2009 United States general population, and after adjusting for age, gender, and differential item function, persons in Saudi Arabia had lower average scores for the physical function (− 3.10), role physical (− 4.75), social function (− 4.23), role emotional (− 5.67), and mental health (− 4.82) scales, as well as the mental health component (− 4.57).ConclusionThis Saudi normative study of patient reported outcomes supported the validity and reliability of the new Saudi SF-36v2 and found cross-national differences with the USA.

Background: The thyroid-related patient-reported outcome measure ThyPRO has become the gold standard for measuring thyroid-related quality of life and uses a 4-week recall period. The impact of the...

Objectives The aim of this study was to describe the development and the content of the Danish Psychosocial Work Environment Questionnaire (DPQ) and to test its reliability and validity. Methods We describe the identification of dimensions, the development of items, and the qualitative and quantitative tests of the reliability and validity of the DPQ. Reliability and validity of a 150 item version of the DPQ was evaluated in a stratified sample of 8958 employees in 14 job groups of which 4340 responded. Reliability was investigated using internal consistency and test-retest reliability. The factorial validity was investigated using confirmatory factor analysis (CFA). For each multi-item scale, we undertook CFA within each job group and multi-group CFA to investigate factorial invariance across job groups. Finally, using multi-group multi-factor CFA, we investigated whether scales were empirically distinct. Results Internal consistency reliabilities and test-retest reliabilities were satisfactory. Factorial validity of the multi-item scales was satisfactory within each of the 14 job groups. Factorial invariance was demonstrated for 10 of the 28 multi-item scales. The hypothesis that the scales of the DPQ were empirically distinct was supported. The final DPQ version consisted of 119 items covering 38 different psychosocial work environment dimensions. Conclusions Overall, the DPQ is a reliable and valid instrument for assessing psychosocial working conditions in a variety of job groups. The results indicate, however, that questions about psychosocial working conditions may be understood differently across job groups, which may have implications for the comparability of questionnaire-based measures of psychosocial working conditions across job groups.

Background: This study aimed to characterize the frequency of self-reported thyroid-related impaired sex life in patients with thyroid diseases, to examine its clinical correlates and relationship with overall quality of life (QOL), and to investigate the effect of treatment. Patients and Methods: Two separate patient samples with benign thyroid diseases were investigated: a cross-sectional sample (759 women and 118 men) treated at two Danish university hospital outpatient clinics, in 2007-2008, and a longitudinal sample (358 women and 74 men) undergoing treatment at the abovementioned centers, during 2008-2012, evaluated before and 6 months after therapy. The thyroid-specific QOL questionnaire ThyPRO was used to measure patient-evaluated thyroid-related sex life impairment. Biochemical and clinical variables were analyzed (i.e., age, education, degree of thyroid dysfunction, comorbidity, serum thyrotropin, total thyroxine, and triiodothyronine, as well as thyroperoxidase and thyrotropin receptor antibody concentrations). The SF-36 Health Survey was used to analyze the effect of impaired sex life on overall QOL. Results: In the cross-sectional sample, 36% of women and 31% of men reported what they perceived to be thyroid-attributable impaired sex life. Women with autoimmune thyroid diseases reported more impairment than those with non-autoimmune thyroid diseases. In patients with Graves' disease lower levels of educational attainment and in patients with toxic nodular goiter comorbidities were associated with impaired sex life. Overall QOL was lower in patients with thyroid-related sex life impairment. In the longitudinal sample, 42% of women and 33% of men had impaired sex life at baseline, which improved at 6 months follow-up only in women and, when analyzing individual diagnoses separately, statistically significantly among those with autoimmune hypothyroidism. Sexual impairment was associated with low education in patients with toxic nodular goiter and with high plasma triiodothyronine concentrations in patients with Graves' disease. In autoimmune hypothyroidism, a younger age was associated with sex life impairment. Conclusion: We found a high frequency of self-reported, thyroid-related sex life impairment in patients with benign thyroid diseases, especially in young women with autoimmune thyroid diseases. Self-perceived impaired sex life persisted in women treated for Graves' disease, suggesting that normalization of thyroid function was not sufficient to restore sexual function.

Purpose: The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys. Materials and methods: Based on the literature, 15 predictor variables were retrieved from the DAnish National working Environment Survey (DANES) and included in a model predicting incident LTSA (≥4 consecutive weeks) during 1-year follow-up in a sample of 4000 DANES participants. The 15-predictor model was reduced by backward stepwise statistical techniques and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without LTSA during follow-up. Results: The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC = 0.68; 95% CI 0.61–0.76), but not practically useful. Conclusions: A prediction model based on occupational health survey variables identified employees with an increased LTSA risk, but should be further developed into a practically useful tool to predict the risk of LTSA in the general working population. Implications for rehabilitation Long-term sickness absence risk predictions would enable healthcare providers to refer high-risk employees to rehabilitation programs aimed at preventing or reducing work disability. A prediction model based on health survey variables discriminates between employees at high and low risk of long-term sickness absence, but discrimination was not practically useful. Health survey variables provide insufficient information to determine long-term sickness absence risk profiles. There is a need for new variables, based on the knowledge and experience of rehabilitation professionals, to improve long-term sickness absence risk profiles.

Background: The positive effects of factor treatment of hemophilia are well established, but the long-term outcomes are not well documented. This panel study evaluated changes in bleeding frequency, joint mobility, physical function, and symptoms in Danish patients with moderate to severe hemophilia A or B over 24 years. Methods: Three anonymous surveys were conducted in 1988, 2001, and 2012 targeting Danish patients with moderate to severe hemophilia, and the study participants, respectively, were 128, 156, and 164 male patients with hemophilia (PWH). The number of bleeding episodes, the use of factor concentrate, comorbidities, joint mobility, physical function, and symptoms were evaluated by means of self-reporting. Trends over time were analyzed using ordinal and multinomial logistic-regression models controlling for age group. Results: The proportion of PWH in the oldest age group (55–88 years) increased from 4% in 1988 to 18% in 2012. In 1988, a high risk of bleeding episodes was primarily found in the age group of 16–34 years. In 2012, a high risk was primarily found in the age group of 35–54 years. Joint mobility and physical function increased significantly from 1988 to 2012 but showed a noticeable decrement in the older age groups, even in 2012. Pain in the extremities, anxiety, and depression decreased significantly, but back pain increased. No significant changes were found for 7 other symptoms. Conclusions: Significant improvements in joint mobility and physical function have occurred over the last 24 years, but PWH > 35 years still experience a decline in these areas with age. This decline underscores the importance of life-long treatment and continuous rehabilitation of PWH.

Objectives The aim was to study work ability in patients with RA compared with the general population by investigating the rates and risks of long-term sickness absence, unemployment and disability pension, and the chance of returning to work and the changes in these risks over time (1994-2011). Methods This was a cohort study with up to 17 years of follow-up (mean 6.95 years/person) including 6677 RA patients of working age (identified in the nationwide DANBIO registry) and 56 955 matched controls from the general population. A multi-state model was used to analyse all shifts between the work-related states (long-term sickness absence, unemployment and disability pension, as well as the chance of returning to work) and calculate hazard rates (HRs). Analyses were stratified by disease duration and controlled for socio-demographic factors, physical job exposure and somatic and psychiatric co-morbidities. Results RA patients had increased risk of long-term sickness absence (e.g. early RA: HR = 4.00, 95% CI: 3.64, 4.30) and disability pension (e.g. established RA: HR = 2.75, 95% CI: 2.54, 2.98) relative to controls. From 1994-99 to 2006-11, a decrease in the effect of established RA was observed [long-term sickness absence: from HR = 2.25 (95% CI: 1.99, 2.54) to 1.63 (95% CI: 1.51, 1.75); and disability pension: from HR = 3.49 (95% CI: 2.83, 4.32) to 2.40 (95% CI: 2.15, 2.69)]. RA patients had a lower chance of returning to work from long-term sickness absence or unemployment (HR = 0.60, HR=0.80), and this did not change over time. Conclusion RA patients remain at high risk for long-term sickness absence and disability pension, despite a positive development between 1996-99 and 2006-11. Returning to work after sick leave or unemployment remains a challenge for RA patients.

Objective To investigate the relation between effort‐reward imbalance (ERI) at work and subsequent weight changes. Methods We included participants from a population‐based cohort of workers in Denmark (mean age = 47 years, 54% women) with two (n = 9005) or three repeated measurements (n = 5710). We investigated the association between (a) ERI (ie, the mismatch between high efforts spent and low rewards received at work) at baseline and weight changes after a 2‐year follow‐up (defined as ≥5% increase or decrease in body mass index (BMI) vs stable), and (b) onset and remission of ERI and subsequent changes in BMI. Using multinomial logistic regression we calculated risk ratios (RR) and 95% confidence intervals (CI), adjusted for sex, age, education, cohabitation, migration background, and follow‐up time. Results After 2 years, 15% had an increase and 13% a decrease in BMI. Exposure to ERI at baseline yielded RRs of 1.09 (95% CI: 0.95‐1.25) and 1.04 (95% CI: 0.90‐1.20) for the increase and decrease in BMI, respectively. There were no differences between sex and baseline BMI in stratified analyses. The onset of ERI yielded RRs of 1.04 (95% CI: 0.82‐1.31) and 1.15 (95% CI: 0.84‐1.57) for subsequent increase and decrease in BMI. The RRs for the remission of ERI and subsequent increase and decrease in BMI were 0.92 (95% CI: 0.71‐1.20) and 0.78 (95% CI: 0.53‐1.13), respectively. Of the ERI components, high rewards were associated with a lower risk of BMI increase. Conclusion ERI was not a risk factor for weight changes. Future studies may investigate whether this result is generalizable to other occupational cohorts and settings.

BackgroundAdverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.MethodWe identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.ResultsWe included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47–2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04–1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94–1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81–1.32).ConclusionsJob strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.

Background: Workplace social capital (WSC) is an emerging topic among both work environment professionalsand researchers. We examined (i) whether high WSC protected against risk of long-term sickness absence (LTSA) ina random sample of the Danish workforce during a 1-year follow-up and (ii) whether the association of WSC withsickness absence was modified by occupational grade. Methods: We measured WSC by self-report in a cohort of3075 employees and linked responses to a national register of sickness absence. We calculated hazard ratios (HRs)and 95% confidence intervals (CIs) of onset of LTSA (21 days), adjusted for covariates. We stratified analyses byoccupational grade and examined if there was an interaction effect of WSC and occupational grade. Results:A one standard deviation higher WSC score predicted a reduced risk of sickness absence after adjustment forsociodemographic variables, prevalent health problems and health behaviours (HR = 0.85, 95% CI = 0.74–0.99). TheHR was attenuated and lost statistical significance after further adjustment for occupational grade (HR = 0.90, 95%CI = 0.78–1.04). When stratified by occupational grade, high WSC predicted a decreased risk of sickness absenceamong higher grade workers (HR = 0.61, 95% CI = 0.44–0.84) but not among lower grade workers (HR = 0.98, 95%CI = 0.83–1.15). The interaction effect of WSC and occupational grade was statistically significant (HR = 0.97, 95%CI = 0.95–0.99). Conclusion: High WSC might reduce risk of LTSA. However, the protective effect appears to belimited to workers of higher occupational grade. Background: Workplace social capital (WSC) is an emerging topic among both work environment professionals and researchers. We examined (i) whether high WSC protected against risk of long-term sickness absence (LTSA) in a random sample of the Danish workforce during a 1-year follow-up and (ii) whether the association of WSC with sickness absence was modified by occupational grade. Methods: We measured WSC by self-report in a cohort of 3075 employees and linked responses to a national register of sickness absence. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) of onset of LTSA (21 days), adjusted for covariates. We stratified analyses by occupational grade and examined if there was an interaction effect of WSC and occupational grade. Results: A one standard deviation higher WSC score predicted a reduced risk of sickness absence after adjustment for sociodemographic variables, prevalent health problems and health behaviours (HR = 0.85, 95% CI = 0.74–0.99). The HR was attenuated and lost statistical significance after further adjustment for occupational grade (HR = 0.90, 95% CI = 0.78–1.04). When stratified by occupational grade, high WSC predicted a decreased risk of sickness absence among higher grade workers (HR = 0.61, 95% CI = 0.44–0.84) but not among lower grade workers (HR = 0.98, 95% CI = 0.83–1.15). The interaction effect of WSC and occupational grade was statistically significant (HR = 0.97, 95% CI = 0.95–0.99). Conclusion: High WSC might reduce risk of LTSA. However, the protective effect appears to be limited to workers of higher occupational grade.

Violence and aggressive behavior within psychiatric facilities are serious work environment problems, which have negative consequences for both patients and staff. It is therefore of great importance to reduce both the number and the severity of these violent incidents to improve quality of care.To evaluate the specificity and sensitivity of the Brøset Violence Checklist (BVC) as a predictor of violent incidents for Danish forensic psychiatry patients.A total of 156 patients were assessed three times daily with the BVC for 24 months. All aggressive or violent incidents were recorded using the Staff Observation Aggression Scale-Revised (SOAS-R). SOAS-R scores of 9 or more defined violent incidents. Data were analyzed using standard logistic regression models as well as models incorporating a random person effect. We used receiver operating curve (ROC) analysis to evaluate different BVC thresholds.Of a total of 139,579 BVC registrations we found 1999 scores above 0 and 419 violent incidents. The BVC score was a strong predictor of violence. For the standard cut-off point of 3, specificity was 0.997 and sensitivity was 0.656. For the general risk of violence seen in this study, the risk of violence given a BVC score3 (positive predictive value) was 37.2%, and the risk of violence given a BVC score3 (negative predictive value) was 0.1%.The BVC showed satisfactory specificity and sensitivity as a predictor of the short-term risk of violence against staff and others by patients in a forensic setting.

Objectives To test the impact of the method of administration (MOA) on score level, reliability, and validity of scales developed in the Patient Reported Outcomes Measurement Information System (PROMIS). Study Design and Setting Two nonoverlapping parallel forms each containing eight items from each of three PROMIS item banks (Physical Function, Fatigue, and Depression) were completed by 923 adults with chronic obstructive pulmonary disease, depression, or rheumatoid arthritis. In a randomized crossover design, subjects answered one form by interactive voice response (IVR) technology, paper questionnaire (PQ), personal digital assistant (PDA), or personal computer (PC) and a second form by PC, in the same administration. Method equivalence was evaluated through analyses of difference scores, intraclass correlations (ICCs), and convergent/discriminant validity. Results In difference score analyses, no significant mode differences were found and all confidence intervals were within the prespecified minimal important difference of 0.2 standard deviation. Parallel-forms reliabilities were very high (ICC = 0.85–0.93). Only one across-mode ICC was significantly lower than the same-mode ICC. Tests of validity showed no differential effect by MOA. Participants preferred screen interface over PQ and IVR. Conclusion We found no statistically or clinically significant differences in score levels or psychometric properties of IVR, PQ, or PDA administration compared with PC.

Studies of labor market outcomes like sickness absence are usually restricted to a single outcome. This paper investigates the use of multi-state models for studying multiple transitions between sick-listing, work, unemployment, and disability pension by analyzing longitudinal register data. Every person sick-listed in Denmark during 2004 was followed until the spring of 2008.A multi-state model was used to analyze transitions between four states: work, sickness absence, unemployment, and disability pension. The first three are possible recurrent states. The predictor variables include age group, gender, geographical region, chronic disease, temporary disease, self-employment sickness absence insurance, and pregnancy. The relative effects of previous transitions were also studied.Risk of transition from sickness absence to disability pension differs with age and geographical region. Those aged 20-29 years have an increased risk of transitioning from work to sickness absence and from sickness absence to unemployment. The self-employed have increased risk of transitioning from work to sickness absence. Those with chronic disease have increased risk of sickness absence, but also a greater probability of returning to work. Previous sickness absence increases the risk of transitioning from work to sickness absence, from sickness absence to unemployment, from work to unemployment, and from work to disability pension.The multi-state model is an effective way of analyzing register data and the transitions between sickness absence, work, unemployment, and disability pension. These methods can be used to develop better predictive models of sickness absence, return to work, unemployment, and disability.

Background Published work assessing psychosocial stress (job strain) as a risk factor for coronary heart disease is inconsistent and subject to publication bias and reverse causation bias. We analysed the relation between job strain and coronary heart disease with a meta-analysis of published and unpublished studies. Methods We used individual records from 13 European cohort studies (1985-2006) of men and women without coronary heart disease who were employed at time of baseline assessment. We measured job strain with questions from validated job-content and demand-control questionnaires. We extracted data in two stages such that acquisition and harmonisation of job strain measure and covariables occurred before linkage to records for coronary heart disease. We defined incident coronary heart disease as the first non-fatal myocardial infarction or coronary death. Findings 30 214 (15%) of 197 473 participants reported job strain. In 1•49 million person-years at risk (mean follow-up 7•5 years [SD 1•7]), we recorded 2358 events of incident coronary heart disease. After adjustment for sex and age, the hazard ratio for job strain versus no job strain was 1•23 (95% CI 1•10-1•37). This effect estimate was higher in published (1•43, 1•15-1•77) than unpublished (1•16, 1•02-1•32) studies. Hazard ratios were likewise raised in analyses addressing reverse causality by exclusion of events of coronary heart disease that occurred in the first 3 years (1•31, 1•15-1•48) and 5 years (1•30, 1•13-1•50) of follow-up. We noted an association between job strain and coronary heart disease for sex, age groups, socioeconomic strata, and region, and after adjustments for socioeconomic status, and lifestyle and conventional risk factors. The population attributable risk for job strain was 3•4%. Interpretation Our findings suggest that prevention of workplace stress might decrease disease incidence; however, this strategy would have a much smaller effect than would tackling of standard risk factors, such as smoking. Funding Finnish Work Environment Fund, the Academy of Finland, the Swedish Research Council for Working Life and Social Research, the German Social Accident Insurance, the Danish National Research Centre for the Working Environment, the BUPA Foundation, the Ministry of Social Affairs and Employment, the Medical Research Council, the Wellcome Trust, and the US National Institutes of Health. CODEN: LANCA

The Danish national return-to-work (RTW) program aims to improve the management of municipal sickness benefit in Denmark. A study is currently ongoing to evaluate the RTW program. The purpose of this article is to describe the study protocol. The program includes 21 municipalities encompassing approximately 19 500 working-age adults on long-term sickness absence, regardless of reason for sickness absence or employment status. It consists of three core elements: (i) establishment of multidisciplinary RTW teams, (ii) introduction of standardized workability assessments and sickness absence management procedures, and (iii) a comprehensive training course for the RTW teams. The effect evaluation is based on a parallel group randomized trial and a stratified cluster controlled trial and focuses on register-based primary outcomes - duration of sickness absence and RTW - and questionnaire-based secondary outcomes such as health and workability. The process evaluation utilizes questionnaires, interviews, and municipal data. The effect evaluation tests whether participants in the intervention have a (i) shorter duration of full-time sickness absence, (ii) longer time until recurrent long-term sickness absence, (iii) faster full RTW, (iv) more positive development in health, workability, pain, and sleep; it also tests whether the program is cost-effective. The process evaluation investigates: (i) whether the expected target population is reached; (ii) if the program is implemented as intended; (iii) how the beneficiaries, the RTW teams, and the external stakeholders experience the program; and (iv) whether contextual factors influenced the implementation. The program has the potential to contribute markedly to lowering human and economic costs and increasing labor force supply. First results will be available in 2013. The trial registrations are ISRCTN43004323, and ISRCTN51445682.

Although the mental health consequences of domestic violence are well documented, empirical evidence is scarce regarding the mental health effects of violence in the workplace. Most studies have used data from small occupation-specific samples, limiting their generalizability. This article examines whether direct exposure to work-related violence is associated with clinically pertinent mental health problems, measured by purchases of psychotropics (antidepressants, anxiolytics, hypnotics), in a cross-occupational sample of 15,246 Danish employees free from using psychotropics at baseline. Self-reported data on work-related violence were merged with other data on purchases of medications through a national registry to estimate cause-specific hazard ratios during 3.6 years (1,325 days) of follow-up in the years 1996-2008. Outcomes were examined as competing risks, and analyses were adjusted for gender, age, cohabitation, education, income, social support from colleagues, social support from supervisor, and influence and quantitative demands at work. Work-related violence was associated with purchasing antidepressants alone (hazard ratio = 1.38, 95% confidence interval: 1.09, 1.75) or in combination with anxiolytics (hazard ratio = 1.74, 95% confidence interval: 1.13, 2.70) but not with purchasing anxiolytics or hypnotics only. The frequency of violent episodes and risk of caseness were unrelated. Work-related violence is associated with increased risk of clinically pertinent mental health problems. Reducing levels of work-related violence may help to prevent mental disorders in the working population.

Objective.To investigate whether patients with Wegener’s granulomatosis (WG) experience reduced health-related quality of life (HRQOL) after accomplishment of remission, and to study the influence of WG-associated organ damage on HRQOL.Methods.Sixty-eight patients with inactive WG and 680 randomly selected, age- and sex-matched controls of the Danish background population completed the Medical Outcomes Study Short-Form 36 (SF-36) survey for evaluation of HRQOL. Irreversible organ damage attributable to WG and/or its treatment was assessed using the Vasculitis Damage Index (VDI).Results.The median disease duration was 7.5 (range 1–26) years in the WG group, and the median total VDI score was 2.0 (range 0–7). Compared to controls, WG patients reported impaired HRQOL reflected by significantly lower SF-36 physical component summary scores (PCS) and mental component summary scores (MCS) (p < 0.001) and by significantly lower scores in 7 out of 8 SF-36 subscales (p ≤ 0.001). In the WG group, no statistically significant correlations were found between the different SF-36 scores and the total VDI score, number of organ systems affected by damage, disease duration, or number of WG relapses. Patients with organ failure or other major forms of damage did not report significantly lower HRQOL than less severely affected patients.Conclusion.WG patients experience significantly reduced HRQOL even in phases with no apparent vasculitis disease activity. Our data indicate that the level of HRQOL does not correlate well with the extent of vasculitis-associated organ damage in WG.

Role functioning is an important part of health-related quality of life. However, assessment of role functioning is complicated by the wide definition of roles and by fluctuations in role participation across the life-span. The aim of this study is to explore variations in role functioning across the lifespan using qualitative approaches, to inform the development of a role functioning item bank and to pilot test sample items from the bank.Eight focus groups were conducted with a convenience sample of 38 English-speaking adults recruited in Rhode Island. Participants were stratified by gender and four age groups. Focus groups were taped, transcribed, and analyzed for thematic content.Participants of all ages identified family roles as the most important. There was age variation in the importance of social life roles, with younger and older adults rating them as more important. Occupational roles were identified as important by younger and middle-aged participants. The potential of health problems to affect role participation was recognized. Participants found the sample items easy to understand, response options identical in meaning and preferred five response choices.Participants identified key aspects of role functioning and provided insights on their perception of the impact of health on their role participation. These results will inform item bank generation.

The aim of this article is to report the development and preliminary testing of a prototype computerized adaptive test of chronic pain (CHRONIC PAIN-CAT) conducted in 2 stages: (1) evaluation of various item selection and stopping rules through real data-simulated administrations of CHRONIC PAIN-CAT; (2) a feasibility study of the actual prototype CHRONIC PAIN-CAT assessment system conducted in a pilot sample. Item calibrations developed from a US general population sample (N = 782) were used to program a pain severity and impact item bank (kappa = 45), and real data simulations were conducted to determine a CAT stopping rule. The CHRONIC PAIN-CAT was programmed on a tablet PC using QualityMetric's Dynamic Health Assessment (DYHNA) software and administered to a clinical sample of pain sufferers (n = 100). The CAT was completed in significantly less time than the static (full item bank) assessment (P.001). On average, 5.6 items were dynamically administered by CAT to achieve a precise score. Scores estimated from the 2 assessments were highly correlated (r = .89), and both assessments discriminated across pain severity levels (P.001, RV = .95). Patients' evaluations of the CHRONIC PAIN-CAT were favorable.This report demonstrates that the CHRONIC PAIN-CAT is feasible for administration in a clinic. The application has the potential to improve pain assessment and help clinicians manage chronic pain.

Objective: To analyze the distribution of effort-reward imbalance (ERI) and to investigate its impact on self-rated health in a representative sample of the Danish workforce. Methods: We studied 4977 employees who responded to a questionnaire in 2000, of which 3470 responded to a follow-up survey in 2005. Results: The highest (ie, most unfavorable) ERI ratio was found in executives in the public sector, social workers, managing clerks in the public sector, and medical secretaries. A one standard deviation increase of the ERI ratio predicted a 12% (95% confidence intervals = 1.01 to 1.24) decline in self-rated health after adjustment for all covariates. Conclusions: This is the first study that identified job groups with a high exposure to ERI in a representative sample of a national workforce. ERI was a risk factor for a decline in self-rated health: (J Occup Environ Med. 2009;51:870-878)

Background: The five-item psychological demands scale of the Job Content Questionnaire (JCQ) has been assumed to be one-dimensional in practice. Purpose: To examine whether the scale has sufficient internal consistency and external validity to be treated as a single scale, using the cross-national JCQ datasetsfrom the United States, Korea, and Japan. Method: Exploratory factor analyses with 22 JCQ items, confirmatory factor analyses with the five psychological demands items, and correlations analyses with mental health indexes. Results: Generally, exploratory factor analyses displayed the predicted demand/ control/support structure with three and four factors extracted. However, at more detailed levels of exploratory and confirmatory factor analyses, the demands scale showed clear evidence of multi-factor structure. The correlations of items and subscales of the demands scale with mental health indexes were similar to those of the full scale in the Korean and Japanese datasets, but not in the U.S. data. In 4 out of 16 sub-samples of the U.S. data, several significant correlations of the components of the demands scale with job dissatisfaction and life dissatisfaction were obscured by the full scale. Conclusion: The multidimensionality of the psychological demands scale should be considered in psychometric analysis and interpretation, occupational epidemiologic studies, and future scale extension.

Objective: The Patient-Reported Outcomes Measurement Information System (PROMIS) was initiated to improve precision, reduce respondent burden, and enhance the comparability of health outcomes measures. We used item response theory (IRT) to construct and evaluate a preliminary item bank for physical function assuming four subdomains. Study Design and Setting: Data from seven samples (N 517,726) using 136 items from nine questionnaires were evaluated. A generalized partial credit model was used to estimate item parameters, which were normed to a mean of 50 (SD 510) in the US population. Item bank properties were evaluated through Computerized Adaptive Test (CAT) simulations. Results: IRT requirements were fulfilled by 70 items covering activities of daily living, lower extremity, and central body functions. The original item context partly affected parameter stability. Items on upper body function, and need for aid or devices did not fit the IRT model. In simulations, a 10-item CAT eliminated floor and decreased ceiling effects, achieving a small standard error (!2.2) across scores from 20 to 50 (reliability O0.95 for a representative US sample). This precision was not achieved over a similar range by any comparable fixed length item sets. Conclusion: The methods of the PROMIS project are likely to substantially improve measures of physical function and to increase the

Objectives. To describe the development and evaluation of the Pain Impact Questionnaire (PIQ-6TM), a six-item measure of pain severity and impact on health-related quality of life (HRQOL) domains. Participants. Two general US population samples (N = 829 and N = 7,025) and one chronic pain patient sample (N = 350) were included. Methods. The PIQ-6TM was developed using conventional and item response theory (IRT) methods in four steps: 1) initial selection and development of items based on results from a previously developed Bodily Pain item bank; 2) final item selection based on new data and investigations of unidimensionality, differential item functioning (DIF), and IRT modeling; 3) development of scoring algorithms, population norms, and cross-calibrations; and 4) psychometric evaluation. Results. Six items on pain intensity and impact satisfied requirements of unidimensionality and lack of DIF and could be scored using IRT methods. The PIQ-6 showed good internal consistency reliability (coefficient alpha = 0.94) and good construct validity. Convergent validity was supported by strong correlations with pain severity scales (visual analog and numerical rating scales; r = 0.81–0.84); discriminant validity was suggested by correlations with the SF-8™ Health Survey Physical and Mental Component Summary measures (r = −0.77; r = −0.32, respectively), significant mean score differences between chronic pain patients and the general population, and between patients differing in self-reported medical conditions (P

Udgivelsesdato: 2007-Jul OBJECTIVE: To identify how thyroid diseases impact the patients' lives and to select the most relevant quality of life (QoL) issues for a thyroid-specific questionnaire. DESIGN: Fifteen thyroid experts and 80 thyroid outpatients (14 with nontoxic goiter, 12 nodular toxic goiter, 21 Graves' disease, 17 thyroid-associated ophthalmopathy, and 16 primary hypothyroidism) were interviewed. METHODS: The relevance of 138 thyroid disease-related issues was rated during interviews. For each issue, three relevance measures were obtained: a diagnosis-specific patient rating, a diagnosis-specific expert rating, and a combined overall patient/expert rating. The 75 most relevant issues overall and the 15 most relevant issues in each patient category were selected. Results: Based on the above, 92 issues were selected, covering a broad range of clinical and QoL domains. Across patient groups, broader QoL domains were most relevant, especially fatigue and emotional susceptibility. However, when focusing on individual patient groups, diagnosis-related physical symptoms were very relevant too. Patients rated issues about psychosocial problems and impact on daily life as more relevant, whereas clinicians focused on thyroid-characteristic issues. CONCLUSIONS: A broad range of QoL issues and physical symptoms are relevant for thyroid patients, particularly fatigue and emotional susceptibility. Patients and clinicians offer complementary perspectives on relevance

Within the framework of item response theory (IRT), we developed a German version of an item bank, as well as a software application that can be employed to measure anxiety by means of a computer adaptive test (CAT). A sample of n = 2348 psychiatric and psychosomatic patients answered a set of up to 13 standardized questionnaires. 81 items drawn from these questionnaires were considered pertinent to the anxiety construct. Various tests were conducted to ensure the suitability of these items for an IRT-based assessment. After these tests, 50 items remained in the item bank and were calibrated using the Generalized Partial Credit Model. Simulation studies conducted on an independent sample of n = 1528 respondents indicate that 6-8 items suffice to measure the latent trait with high precision (standard erroror= 0.32). CAT scores correlated highly with scores estimated from all available items (r = .97) and scale scores of the State Trait Anxiety Inventory (STAI, state scale, r = .93). Within a routine clinical setting, 102 in-patients answered the Anxiety-CAT along with a number of established anxiety questionnaires. The correlation between the Anxiety-CAT and the STAI state scale was still high (r = .60), but lower than the correlations found in the simulation studies. The Anxiety-CAT was able to differentiate between mental health disorders in a similar manner as established questionnaires. These results suggest that the Anxiety-CAT does indeed exhibit the advantages expected from theory, but the results of further studies are needed in order to judge its full potential for research and clinical practice.

To propose the minimally important difference (MID) for the SF-36 Vitality (VT) scale by evaluating the association of score differences with clinical conditions and functional outcomes.Analyses were performed on data from the Medical Outcomes Study (n = 3445). The first analyses regressed VT scores (0-100 scale) on chronic conditions that cause fatigue in order to determine the impact of each condition on VT. The second set of analyses examined the relationship between baseline VT scores and other outcomes at baseline, 1-year, and 7-year follow-up.VT scores were significantly reduced in patients with anemia [5 points (95% CI 2-9 points)], CHF [6 (3-9) points], and COPD [6 (3-9) points]. Decreases in VT score were significantly associated with increased odds of negative outcomes, including inability to work due to health at baseline [OR (5 points) = 1.27 (95% CI 1.24-1.31), OR (10 points) = 1.62 (1.54-1.71)], job loss at 1 year [OR (5) = 1.13 (1.08-1.19), OR (10) = 1.28 (1.17-1.41)], hospitalization at 1 year [OR (5) = 1.08 (1.05-1.11), OR (10) = 1.17 (1.10-1.23)], short-term mortality [0-18 months-Hazard Ratio (HR) (5) = 1.10-1.71, HR (10) = 1.21-2.39, depending on VT level] and long-term mortality [19+ months-HR (5) = 1.05-1.31, HR (10) = 1.10-1.54]. The mortality risk increase was largest at low VT levels.VT decrements of 5-10 points were seen for diseases known to cause fatigue. Further, differences of 5-10 points in the VT score were associated with significant increased risk of negative outcomes. We recommend an MID of 5 points for analyses of groups with VT scores below average. For follow-up of individual patients, we recommend a 10-point difference as important.

This paper reviews important methodological considerations for developing item banks and computerized adaptive scales (commonly called computerized adaptive tests in the educational measurement literature, yielding the acronym CAT), including issues of the reference population, dimensionality, dichotomous versus polytomous response scales, differential item functioning (DIF) and conditional scoring, mode effects, the impact of local dependence, and innovative approaches to assessment using CATs in health outcomes research.

This study examined whether psychological distress in newly diagnosed breast cancer patients was associated with their survival. We analyzed data from 1,588 breast cancer patients who filled in the EORTC QLQ-C30 questionnaire and the Hospital Anxiety and Depression Scale (HADS) 2 months after their primary operation. The median follow-up time was 12.9 years. Psychological distress (EORTC QLQ-C30 emotional function; HADS anxiety; HADS depression) and EORTC fatigue, physical function, and overall ratings were used to predict recurrence-free and overall survival, controlling for the known clinical and histopathological prognostic factors (biological model) using Cox multivariate regression analysis. Low levels of psychological distress (good EORTC emotional function) and low fatigue independently predicted longer recurrence-free and overall survival, controlling for biological factors. Lack of anxiety (HADS) also predicted longer recurrence-free survival. When added in combination to the biological model, fatigue remained a significant predictor of recurrence-free survival (P = 0.0004; risk ratio 1.32 (1.13-1.54)) and emotional function remained a significant predictor of overall survival (P = 0.0074; risk ratio 0.81 (0.70-0.95)). Low psychological distress and a low level of fatigue may cause a greater cancer resistance or may reflect underlying mental and physical robustness.

Background and Objective The goal was to develop a shortened version of the EORTC QLQ-C30 for use in palliative care. We wanted to keep as few items as possible in each scale while still being able to compare results with studies using the original scales. We examined the possibilities of shortening the physical functioning, cognitive functioning, fatigue, and nausea and vomiting scales. Study Design and Setting The shortening was based on 2,366 (physical functioning) and 10,815 (three other scales) observations, respectively. We used item response theory to construct scoring algorithms for predicting scores on the original scales. Results Evaluations showed that a three-item physical scale, a two-item fatigue scale, and a one-item nausea or vomiting scale predicted the scores on the original scales with excellent agreement and had measurement abilities similar to the original scales with no loss or only a little loss in power to detect group differences. The results of the cognitive functioning scale indicated problems when predicting scores from a shortened version. Conclusion Given the favorable results for the physical functioning, fatigue, and nausea or vomiting scales we expect that the shortened versions of these scales will be included in the abbreviated version of the EORTC QLQ-C30 for palliative care.

This article presents a framework for the use of latent variables as outcomes in regression analysis. Based on loglinear Rasch models where item parameters are known or estimated using conditional maximum likelihood a simple and fast estimation algorithm is proposed. The interpretation of regression parameters in the presence of random effects is discussed. A regression model based on a loglinear Rasch model is used to model general and specific group differences in an occupational health study.

During the Intervention Project on Absence and Well-being (IPAW), a 5-year project conducted in Denmark, we investigated psychosocial work environment factors as independent predictors of the number of absence days per year. The present two-year longitudinal study used the IPAW cohort, but was not intended to study intervention effects, which will be reported later. Data were derived from baseline questionnaires and employers’ registers of absence for 1919 participants (1305 women, 614 men, mainly in low-skilled jobs) in different occupations from 52 workplaces. These workplaces included municipal care, municipal technical services and a large pharmaceutical company. Analyses were performed by Poisson regression accounting for over-dispersion. After controlling for age, family type, health behaviours and physical work environment variables, we found that high levels of decision authority predicted low absence rates in both women and men. We tested two new psychosocial constructs developed for this study: ...

During recent years many researchers have criticized the widely used scales on psychological job demands. For instance, they comment that in most cases different types of demand seem to be mixed in one measure. In this paper we analyse the scale on quantitative job demands in the recently developed Copenhagen Psychosocial Questionnaire (COPSOQ), with special emphasis on Differential Item Functioning (DIF). DIF refers to basic differences between groups of respondents, which may affect how they respond to questionnaire items. The data material for our study comprised a representative sample of Danish employees. The respondents were categorized into 32 specific jobs according to the International Standard Classification of Occupations (ISCO 1968). We analysed DIF with respect to the respondents’ jobs with logistic regression analyses. These analyses showed that the items used in the original demand scale functioned very differently for different jobs in the population. The conclusion is that scales on quant...

In a large number of situations, activities in health care have to be measured in terms of outcome and cost. However, the cases where outcome is fully captured by a single measure are rather few, so that one uses some index for outcome, computed by weighing together several outcome measures using subjective and somewhat arbitrary weights. In the paper we propose an approach to cost-effectiveness analysis where such artificial aggregation is avoided. This is achieved by assigning to each activity the weights which are the most favourable in a comparison with the other options available, so that activities which have a poor score in this method are guaranteed to be inferior. The method corresponds to applying Data envelopment analysis, known from the theory of productivity, to the context of health economic evaluations. The method is applied to an analysis of the cost-effectiveness of alternative health plans using data from the Medical Outcome Study (JAMA 1996; 276: 1039-1047), where outcome is measured as improvement in mental and physical health.

Objectives The aims of this study were (i) to describe the trends in the work environment in 1990-2000 among employees in Denmark and (ii) to establish whether these trends were attributable to labor-force changes. Methods The split-panel design of the Danish Work Environment Cohort Study includes interviews with three cross-sections of 6067, 5454, and 5404 employees aged 18-59 years, each representative of the total Danish labor force in 1990, 1995 and 2000. In the cross-sections, the participation rate decreased over the period (90% in 1990, 80% in 1995, 76% in 2000). The relative differences in participation due to gender, age, and region did not change noticeably. Results Jobs with decreasing prevalence were clerks, cleaners, textile workers, and military personnel. Jobs with increasing prevalence were academics, computer professionals, and managers. Intense computer use, long workhours, and noise exposure increased. Job insecurity, part-time work, kneeling work posture, low job control, and skin contact with cleaning agents decreased. Labor-force changes fully explained the decline in low job control and skin contact to cleaning agents and half of the increase in long workhours, but not the other work environment changes. Conclusions The work environment of Danish employees improved from 1990 to 2000, except for increases in long workhours and noise exposure. From a specific work environment intervention point of view, the development has been less encouraging because declines in low job control, as well as skin contact to cleaning agents, were explained by labor-force changes.

A fundamental assumption of most IRT models is that items measure the same unidimensional latent construct. For the polytomous Rasch model two ways of testing this assumption against specific multidimensional alternatives are discussed. One, a marginal approach assuming a multidimensional parametric latent variable distribution, and, two, a conditional approach with no distributional assumptions about the latent variable. The second approach generalizes the Martin-Lof test for the dichotomous Rasch model in two ways: to polytomous items and to a test against an alternative that may have more than two dimensions. A study on occupational health is used to motivate and illustrate the methods.

The authors used multigroup confirmatory factor analysis and structural equations models to examine the construct validity and item functioning of the five-item General Health (GH) scale from the SF-36 in Danes over 16 years of age ( n = 4,084). They included four criteria variables for physical and mental health. Items GH2-GH5 had low response rates among the elderly, probably due to the compact layout of these items in the questionnaire. The authors found differential item functioning for several items, indicating some degree of multidimensionality in the GH scale. Thus, GH1 had stronger associations with age, physical functioning, and chronic diseases than predicted by the one-factor model. However, psychometrical problems were mostly found in the youngest age group. If the problem of missing values is solved by layout changes or interview administration, the GH scale appears to be a valid measure of self-rated health in elderly populations.