Validation of the Dutch Quality of Life in Hand Eczema Questionnaire (QOLHEQ).

BACKGROUND: Measurement instruments should be validated for use in the population for which they are intended. The Quality of Life in Hand Eczema Questionnaire (QOLHEQ) has been developed to measure impairment of health-related quality of life in patients with hand eczema. OBJECTIVES: To assess validity, reproducibility, responsiveness and interpretability of the Dutch version of the QOLHEQ. METHODS: This was a prospective validation study in adult patients with hand eczema. At three time points (T0 , baseline; T1 , after 1-3 days; T2 , after 4-12 weeks), data from the QOLHEQ and multiple reference instruments were collected. Scale structure was assessed using item response theory analysis and structural equation modelling (SEM). Single-score validity and responsiveness were tested with hypotheses on correlations with reference instruments. Concerning reproducibility, intraclass correlation coefficients (ICCagreement ) and standard error of agreement (SEMagreement ) were checked. Regarding interpretability, bands for severity of quality-of-life impairment were proposed. Also, smallest detectable change (SDC) and minimally important change (MIC) were determined. RESULTS: At T0 , 300 individuals participated in the study (54% were male, mean age 45 years). Rescoring of the scale structure fitted the Rasch model and the SEM. The ICCagreement was 0·91 (95% confidence interval 0·85-0·94) and the SEMagreement was 5·2 points. Of the a priori formulated hypotheses, 80% (single-score validity) and 64% (change scores for responsiveness) were confirmed. The SDC was 14·4 points and the MIC was 11·5 points. CONCLUSIONS: The Dutch version of the QOLHEQ has a good structural validity and reproducibility and has a high single-score validity and moderate responsiveness. An improvement of ≥ 15 points should be regarded as a real, important change within the Dutch population. What's already known about this topic? The Quality of Life in Hand Eczema Questionnaire (QOLHEQ) measures impairment of health-related quality of life (HRQoL) in patients with hand eczema. The QOLHEQ was validated in Germany and Japan, but the validity and interpretability of the Dutch version are unknown. What does this study add? This study shows that the Dutch QOLHEQ is a valid instrument to measure HRQoL impairment in Dutch patients with hand eczema, demonstrating good reliability and moderate responsiveness. Methods of item response theory are applied to assess and refine the scoring structure. Severity gradings to interpret single and change scores, specifically in Dutch patients, are proposed. What are the clinical implications of this work? The Dutch QOLHEQ can now be used to measure HRQoL impairment in Dutch patients with hand eczema.

[Epidemiology of hand eczema in Germany : A retrospective view of the past 10 years of hand eczema research in Germany]. / Epidemiologie des Handekzems in Deutschland : Ein Rückblick auf die letzten 10 Jahre Handekzemforschung in Deutschland.

BACKGROUND: There is a lack of epidemiological data describing patterns of hand eczema with reference to the general German population. OBJECTIVE: Epidemiological data were extracted from all internationally published clinical studies which investigated hand eczema in Germany. MATERIAL AND METHODS: A search was carried out for all clinical studies performed in Germany in the previous 10 years involving hand eczema patients. Inclusion criteria were that at least one author was listed with a German affiliation, that the study included original data and was published in an international journal with peer review. RESULTS: This review included 39 studies, which were performed based on 29 original data sets. The median proportion of women was 53.7% and the median age 45.1 years. The 1­year prevalence of hand eczema varied depending on the sample and type of data collection from 0.24% to 9.2%. The lifetime prevalence was estimated to be 2.6-16.0% and the point prevalence in dermatological practice was 6.7 %. In studies assessing the impact of hand eczema in specific occupations, women were underrepresented, large studies were carried out for metal workers but only a few small studies for nursing personnel. CONCLUSION: There is a lack of knowledge concerning the epidemiology of hand eczema in the general German population. While international studies found the first occurrence of hand eczema to be between the ages of 26 and 28 years, the mean age of patients seen in private dermatological practice in Germany was 20 years higher. These findings suggest that patients do not consult a dermatologist when hand eczema first appears, which can lead to a more severe course of the disease.

Prevalence of skin disease in a population-based sample of adults from five European countries.

BACKGROUND: There is a lack of prevalence data on skin diseases in the general adult population; most studies have been carried out in small, national or consecutive clinical samples. OBJECTIVES: To determine the prevalence of common skin disease in the general European population and to assess differences in the characteristics of treatment between countries. METHODS: A random sample consisting of 12 377 participants aged 18-74 years was drawn from the general population of five European countries (Germany, Italy, the Netherlands, Portugal and Sweden). This was a cross-sectional study and all participants were interviewed using a standardized questionnaire that assessed the occurrence of 10 common skin diseases during lifetime, past year and past month. If a skin disease was reported, we additionally assessed who performed the diagnosis and treatment, and whether drugs had been prescribed. RESULTS: The most common skin disease was warts (41·3%), followed by acne (19·2%) and contact dermatitis (15·0%). In general, women were more often affected by skin diseases compared with men; only skin cancer had a slightly higher prevalence in men. The prevalence of skin diseases in northern countries (Germany, the Netherlands and Sweden) was generally higher than in the southern countries (Italy and Portugal). In the Netherlands the treatment of skin diseases was less often performed by a dermatologist compared with the other countries. CONCLUSIONS: The prevalence estimates reported in this study are derived from a representative sample of the general population. Data assessment was performed comprehensively across countries, thus country-specific prevalence estimates are comparable.

Patterns of chronic hand eczema: a semantic map analysis of the CARPE registry data.

BACKGROUND: Hand eczema has a high incidence and prevalence and has a negative impact on both physical and psychological well-being, with the risk of persistence as a chronic condition. Epidemiological studies on hand eczema provided mainly descriptive and risk analyses, but pattern analyses of variables associated with hand eczema, in particular chronic hand eczema, have not been explored to date. OBJECTIVES: To investigate and display the semantics of associations between variables of hand eczema obtained from the Swiss and German registries of chronic hand eczema (CARPE) to dissect patterns and novel links. METHODS: This was a cross-sectional study on selected variables from the CARPE registries. Associations between variables were analysed by means of an autoassociative system. A semantic connectivity map was generated by using a maximum spanning tree algorithm. RESULTS: Baseline datasets of 1466 patients with chronic hand eczema (Switzerland: 199; Germany: 1267) were analysed. Occupational exposure had the highest impact in the total and country cohorts. We identified two areas of exposure linked to corresponding occupations that clearly demarcated the sexes. CONCLUSIONS: This study, using semantic connectivity as a novel method of data analysis, reveals the complexity of features characterizing chronic hand eczema as well as novel association patterns that deserve further investigation.

Prevalence of contact allergy in the general population in different European regions.

BACKGROUND: Population-based studies about contact allergy are scarce. OBJECTIVES: To obtain reliable estimates of the prevalence of contact allergy in the general population in Europe. METHODS: A cross-sectional study of a random sample from the general population, aged 18-74 years, in five different European countries (Sweden, the Netherlands, Germany, Italy and Portugal). In total, 12 377 subjects were interviewed and a random sample (n = 3119) patch tested to TRUE Test panels 1-3 and Fragrance Mix (FM) II, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) and sesquiterpene lactone mix. A positive patch test reaction is considered as contact allergy. RESULTS: In total, 27·0% [95% confidence interval (CI) 25·5-28·5] had at least one positive reaction to an allergen of the European baseline series, with a significantly higher prevalence in women than in men. The highest age-standardized prevalences (≥ 1%) were found for nickel (14·5%, 95% CI 13·2-15·8), thiomersal (5·0%, 95% CI 4·2-5·8), cobalt (2·2%, 95% CI 1·7-2·7), FM II (1·9%, 95% CI 1·5-2·5), FM I (1·8%, 95% CI 1·4-2·3), HICC (1·4%, 95% CI 1·0-1·9), p-tert-butylphenol formaldehyde resin (1·3%, 95% CI 0·9-1·7) and para-phenylenediamine (1·0%, 95% CI 0·6-1·3). Only nickel and thiomersal showed a statistically significantly different prevalence for contact allergy among the different European populations. Subjects reporting contact dermatitis in their lifetime (age-standardized prevalence 15·1%, 95% CI 13·8-16·3) had an increased risk for contact allergy (odds ratio 1·9, 95% CI 1·5-2·5). The risk of having a contact allergy was not increased in those with atopic dermatitis (prevalence 7·6%, 95% CI 6·7-8·6; odds ratio 1·0, 95% CI 0·7-1·4). CONCLUSIONS: Contact allergy to at least one allergen of the European baseline series was diagnosed in more than one-quarter of the general European population. Therefore measures to improve the primary prevention of contact allergy have to be enforced.

The Quality of Life in Hand Eczema Questionnaire (QOLHEQ): validation of the German version of a new disease-specific measure of quality of life for patients with hand eczema.

BACKGROUND: Health-related quality of life (HRQOL) is widely used as a patient-reported outcome to evaluate clinical trials. In routine care it can also be used to improve treatment strategies or to enhance patients' self-awareness and empowerment. Therefore a disease-specific instrument is needed that assesses in detail all the impairments caused by the disease of interest. For patients with hand eczema (HE) such an instrument was developed by an international expert group, but its measurement properties are unknown. OBJECTIVES: To validate the German version of the Quality of Life in Hand Eczema Questionnaire (QOLHEQ), which covers the domains of (i) symptoms, (ii) emotions, (iii) functioning and (iv) treatment and prevention. METHODS: The QOLHEQ was assessed up to three times in 316 patients with HE to test reliability and sensitivity to change. To test construct validity we also assessed several reference measures. The scale structure was analysed using the Rasch model for each subscale and a structural equation model was used to test the multi domain structure of the QOLHEQ. RESULTS: After minor adaptions of the scoring structure, all four subscales of the QOLHEQ did not significantly misfit the Rasch model (α > 0·05). The fit indices of the structural equation model showed a good fit of the multi domain construct with four subscales assessing HRQOL. Nearly all a priori-defined hypotheses relating to construct validity could be confirmed. The QOLHEQ showed a sensitivity to change that was superior compared with all reference measures. CONCLUSIONS: The QOLHEQ is ready to be used in its German version as a sensitive outcome measure in clinical trials and for routine monitoring. The treatment-relevant subscales enable its use to enhance patients' self-awareness and to monitor treatment decisions.