Validation of the 8-item Attitudes Towards Gambling Scale (ATGS-8) in a British population survey

Introduction. Public opinions concerning gambling are an important factor in shaping public policy. Little empirical attention has been given to assessing gambling attitudes within the general population. The aim of the present study is to validate the 8-item Attitudes Towards Gambling Scale (ATGS-8) in British individuals and to investigate associations of these attitudes with frequency of gambling and gambling problems. Methods. Data were derived from 7746 individuals participating in the British Gambling Prevalence Survey 2010, a comprehensive interview-based survey conducted in Great Britain between November 2009 and May 2010. Confirmatory factor analysis and separate regression analyses were applied. Results. The one-dimensional structure of the ATGS-8 was confirmed in the community sample and by gender. Furthermore, more positive attitudes towards gambling were positively related to frequency of gambling and gambling problems. Conclusions. The present study extends the previous evaluations of the scale by providing detailed evidence for the utility and usefulness of the ATGS-8 in a community sample and across gender. The ATGS-8 is a valid instrument to assess public opinion on gambling among the general population

Reimagining the General Health Questionnaire as a measure of emotional wellbeing: A study of postpartum women in Malta

Background: Postpartum health has been subject to a focus on psychological morbidity, despite positive associations between postpartum recovery and maternal emotional wellbeing. There are currently many validated tools to measure wellbeing and related concepts, including non-psychiatric morbidity. The General Health Questionnaire, 12 items (GHQ-12) is one such instrument, widely used and validated in several languages. Its use in postpartum settings has been documented with disagreement about the instrument's utility in this population, particularly in relation to scoring method and threshold. The GHQ-12 has never been translated into Maltese. This study explored the psychometric properties of the GHQ-12 in a Maltese postpartum population to consider if the use of a different scoring method (visual analogue scale) in the GHQ-12 can determine postpartum wellbeing. Methods: One hundred and twenty-four postpartum women recruited from one hospital in Malta completed the translated and adapted GHQ-12 as a wellbeing measure (GHQ-12(WB)) at four postpartum time points. The psychometric properties of the GHQ-12(WB) were explored using confirmatory factor analysis, discriminant and divergent validity and reliability analysis. Results: The GHQ-12(WB) demonstrated good divergent and known-groups validity and internal consistency. No models offered a good fit to the data. The overall consistent best-fit to the data was an eight item, two factor model (GHQ-8). Model fit improved across all models in terms of CFI at 13 weeks. Conclusion: Findings generally support the reliability and validity of the Maltese version of the GHQ-12(WB). Model fit changes over time reflect the dynamic nature of postpartum recovery. Further evaluation of the GHQ-8(WB) is recommended. © 2013 Australian College of Midwives

Added predictive value of high-throughput molecular data to clinical data, and its validation

Hundreds of ''molecular signatures'' have been proposed in the literature to predict patient outcome in clinical settings from high-dimensional data, many of which eventually failed to get validated. Validation of such molecular research findings is thus becoming an increasingly important branch of clinical bioinformatics. Moreover, in practice well-known clinical predictors are often already available. From a statistical and bioinformatics point of view, poor attention has been given to the evaluation of the added predictive value of a molecular signature given that clinical predictors are available. This article reviews procedures that assess and validate the added predictive value of high-dimensional molecular data. It critically surveys various approaches for the construction of combined prediction models using both clinical and molecular data, for validating added predictive value based on independent data, and for assessing added predictive value using a single data set

Used-habitat calibration plots: a new procedure for validating species distribution, resource selection, and step-selection models

“Species distribution modeling” was recently ranked as one of the top five “research fronts” in ecology and the environmental sciences by ISI's Essential Science Indicators (Renner and Warton 2013), reflecting the importance of predicting how species distributions will respond to anthropogenic change. Unfortunately, species distribution models (SDMs) often perform poorly when applied to novel environments. Compounding on this problem is the shortage of methods for evaluating SDMs (hence, we may be getting our predictions wrong and not even know it). Traditional methods for validating SDMs quantify a model's ability to classify locations as used or unused. Instead, we propose to focus on how well SDMs can predict the characteristics of used locations. This subtle shift in viewpoint leads to a more natural and informative evaluation and validation of models across the entire spectrum of SDMs. Through a series of examples, we show how simple graphical methods can help with three fundamental challenges of habitat modeling: identifying missing covariates, non-linearity, and multicollinearity. Identifying habitat characteristics that are not well-predicted by the model can provide insights into variables affecting the distribution of species, suggest appropriate model modifications, and ultimately improve the reliability and generality of conservation and management recommendations

Modern psychometrics applied in rheumatology - a systematic review

Background Although item response theory (IRT) appears to be increasingly used within health care research in general, a comprehensive overview of the frequency and characteristics of IRT analyses within the rheumatic field is lacking. An overview of the use and application of IRT in rheumatology to date may give insight into future research directions and highlight new possibilities for the improvement of outcome assessment in rheumatic conditions. Therefore, this study systematically reviewed the application of IRT to patient-reported and clinical outcome measures in rheumatology. Methods Literature searches in PubMed, Scopus and Web of Science resulted in 99 original English-language articles which used some form of IRT-based analysis of patient-reported or clinical outcome data in patients with a rheumatic condition. Both general study information and IRT-specific information were assessed. Results Most studies used Rasch modeling for developing or evaluating new or existing patient-reported outcomes in rheumatoid arthritis or osteoarthritis patients. Outcomes of principle interest were physical functioning and quality of life. Since the last decade, IRT has also been applied to clinical measures more frequently. IRT was mostly used for evaluating model fit, unidimensionality and differential item functioning, the distribution of items and persons along the underlying scale, and reliability. Less frequently used IRT applications were the evaluation of local independence, the threshold ordering of items, and the measurement precision along the scale. Conclusion IRT applications have markedly increased within rheumatology over the past decades. To date, IRT has primarily been applied to patient-reported outcomes, however, applications to clinical measures are gaining interest. Useful IRT applications not yet widely used within rheumatology include the cross-calibration of instrument scores and the development of computerized adaptive tests which may reduce the measurement burden for both the patient and the clinician. Also, the measurement precision of outcome measures along the scale was only evaluated occasionally. Performed IRT analyses should be adequately explained, justified, and reported. A global consensus about uniform guidelines should be reached concerning the minimum number of assumptions which should be met and best ways of testing these assumptions, in order to stimulate the quality appraisal of performed IRT analyses

The Dutch Individualised Care Scale for patients and nurses : a psychometric validation study

Aims and objectives: Translating and psychometrically assessing the Individualised Care Scale (ICS) for patients and nurses for the Flemish and Dutch healthcare context. Background: Individualised care interventions have positive effects on health outcomes. However, there are no valid and reliable instruments for evaluating individualised care for the Flemish and Dutch healthcare context. Design: Psychometric validation study. Setting and participants: In Flemish hospitals, data were collected between February and June 2016, and in Dutch hospitals, data were collected between December 2014 and May 2015. Nurses with direct patient contact and a working experience of minimum 6 months on the wards could participate. Patient inclusion criteria were being an adult, being mentally competent, having an expected hospital stay of minimum 1 day, and being able to speak and read the Dutch language. In total, 845 patients and 569 nurses were included. Methods: The ICS was translated into Dutch using a forward–backward translation process. Minimal linguistic adaptations to the Dutch ICS were made to use the scale as a Flemish equivalent. Omega, Cronbach’s Alpha, mean inter-item correlations and standardised subscale correlations established the reliability and confirmatory factor analysis the construct validity of the ICS. Results: Internal consistency using Omega (Cronbach’s Alpha) ranged from 0.83 to 0.96 (0.82–0.95) for the ICSNurse and from 0.88 to 0.96 (0.87–0.96) for the ICSPatient. Fit indices of the confirmatory factor analysis indicated a good model fit, except for the root mean square error of approximation, which indicated only moderate model fit. Conclusion: The Dutch version of the ICS showed acceptable psychometric performance, supporting its use for the Dutch and Flemish healthcare context. Relevance to clinical practice: Knowledge of nurses’ and patients’ perceptions on individualised care will aid to target areas in the Dutch and Flemish healthcare context in which work needs to be undertaken to provide individualised nursing care

Factorial structure of the Manchester short assessment of quality of life in patients with schizophrenia-spectrum disorders

Purpose Subjective quality of life is a central patient-reported outcome in schizophrenia-spectrum disorders. The Manchester Short Assessment of Quality of Life (MANSA) is an established and widely used instrument for its assessment. The present study is a secondary analysis of large schizophrenia studies and aims to establish the factorial structure of the MANSA with a rigorous two-step methodology. Methods A sample of 3120 patients was randomly split into two datasets; the first includes two thirds of the patients and serves as the calibration sample (N = 2071) and the second includes one third of them and serves as the validation sample (N = 1049). We performed an exploratory factor analysis with the calibration sample followed by a confirmatory factor analysis with the validation sample. Results Our results for both samples revealed a model with adequate fit comprising two factors. The first factor encompasses eight items measuring satisfaction with a variety of life and health-related aspects of quality of life, whereas the second consists of four items assessing satisfaction with living environment comprising living alone or with others, accommodation, family, and safety. These two factors correlate in a different way with socio-demographic characteristics such as age and living conditions. Conclusions Future trials and service evaluation projects using the MANSA to measure quality of life should take into account that satisfaction with living environment may be distinct from satisfaction with other life and health-related aspects of quality of life

The Dutch language version of the Toronto structured interview for Alexithymia: reliability, concurrent validity, and factor structure

The aim of this study was to evaluate the psychometric properties of the Dutch version of the Toronto Structured Interview for Alexithymia (TSIA) in a clinical sample. The TSIA and the 20-item Toronto Alexithymia Scale (TAS-20) were administered to 85 psychiatric inpatients and to 76 medical outpatients with the symptom of tinnitus. Both internal and inter-rater reliability were acceptable. Confirmatory factor analyses supported the hierarchical, 4-factor structure with 4 lower-order factors nested within 2 higher-order latent factors, previously obtained with English, German, and Italian versions. Concurrent validity was supported by significant correlations between the TSIA and the TAS-20 total scores although there were some differences between the psychiatric subsample and the medical subsample. While further studies are needed to assess the convergent and discriminant validity of the TSIA, the results support its use as a measure of alexithymia