Josep-Maria Losilla

Wording effects and the factor structure of the 12-item General Health Questionnaire (GHQ-12)

The 12-item version of the General Health Questionnaire (GHQ-12) has become a popular screening instrument with which to measure general psychological health in different settings. Previous studies into the factorial structure of the GHQ-12 have mainly supported multifactor solutions, and only a few recent works have shown that the GHQ-12 was best represented by a single substantive factor when method effects associated with negatively worded items were considered. Confirmatory factor analysis was applied to compare competing measurement models from previous research, including correlated traits-correlated methods and correlated traits-correlated uniquenesses approaches, to obtain further evidence about the factorial structure of the GHQ-12. This goal was achieved with data from 3,050 participants who completed the GHQ-12 included in the Catalonian Survey of Working Conditions (Catalonian Labor Relations and Quality of Work Department, 2012). The results showed additional evidence that the GHQ-12 has a unidimensional structure after controlling for method effects associated with negatively worded items. Furthermore, we found evidence for our hypothesis about the spurious nature of the 3-factor solution in Graetzs (1991) model after comparing its fit with that found for alternative models resulting from different combinations of the negatively worded items. An implication of our results is that future research about the factor structure of the GHQ-12 should take method effects associated with negative wording into account in order to avoid reaching inaccurate conclusions about its dimensionality.

Exploring working conditions as determinants of job satisfaction: an empirical test among Catalonia service workers

Job satisfaction is particularly important in the service industries since it involves direct contact with customers and thus has a direct influence on company performance. This paper analyses the impact of 10 working conditions on job satisfaction by means of structural equation modeling in a representative stratified random sample of 1553 service sector employees in Catalonia, Spain. Significant effects in social aspects (recognition of a job well done and social support) were found, followed by psychological loads (emotional demands and job insecurity) and by task contents (development and meaning, and predictability). These variables explained 50% of the variance in job satisfaction.

Count data in psychological applied research.

As some authors have noticed in fields other than psychology, level of measurement and distributional characteristics of count data are commonly not taken into account, so that they are analysed as normally distributed continuous variables, and therefore some general linear model is applied. In this work, we review a random sample of 457 articles published in the last four years in journals with the highest impact factor in the Journal Citation Reports (JCR Social Sciences Edition) of the Institute for Scientific Information. The goals are to know how often count variables appear in psychological applied research and which data analyses are used when dealing with count response variables. Examination showed that there is a notable presence of count variables, especially in some topics in psychology and a remarkable misapplication of the general linear model. One deals with causes and consequences of this approach to data analysis and suggests the use of specific models to analyse count data.

Methodological quality is underrated in systematic reviews and meta-analyses in health psychology

OBJECTIVES In this paper, we compile and describe the main approaches proposed in the literature to include methodological quality (MQ) or risk of bias (RoB) into research synthesis. We also meta-review how the RoB of observational primary studies is being assessed and to what extent the results are incorporated in the conclusions of research synthesis. STUDY DESIGN AND SETTING Electronic databases were searched for systematic reviews or meta-analyses related to health and clinical psychology. A random sample of 90 reviews published between January 2010 and May 2016 was examined. RESULTS A total of 46 reviews (51%) performed a formal assessment of the RoB of primary studies. Only 17 reviews (19%) linked the outcomes of quality assessment with the results of the review. CONCLUSION According to the previous literature, our results corroborate the lack of guidance to incorporate the RoB assessment in the results of systematic reviews and meta-analyses. Our recommendation is to appraise MQ according to domains of RoB to rate the degree of credibility of the results of a research synthesis, as well as subgroup analysis or meta-regression as analytical methods to incorporate the quality assessment.

Overdispersion Tests in Count-Data Analysis

Count data are commonly assumed to have a Poisson distribution, especially when there is no diagnostic procedure for checking this assumption. However, count data rarely fit the restrictive assumptions of the Poisson distribution. The violation of much of such assumptions commonly results in overdispersion, which invalidates the Poisson distribution. Undetected overdispersion may entail important misleading inferences, so its detection is essential. In this study, different overdispersion diagnostic tests are evaluated through two simulation studies. In Exp. 1, the nominal error rate is compared under different sample sizes and Λ conditions. Analysis shows a remarkable performance of the χ2 df test. In Exp. 2 and 3, statistical power is compared under different sample sizes, Λ, and overdispersion conditions. χ2 and LR tests provide the highest statistical power.

Instruments to assess the patient comfort during hospitalization: a psychometric review protocol

AIM The aim of this study was to analyse the psychometric properties, outcomes and utility of instruments measuring the patient comfort during hospitalization. BACKGROUND While there are numerous systematic reviews assessing the psychometric properties of healthcare instruments, none of them is devoted to evaluate the psychometric properties of instruments measuring comfort, which is considered an indicator of quality in health care and is associated to quicker discharges, increased patient satisfaction and stronger cost-benefit ratios for the institution. DESIGN Psychometric Systematic review. METHODS Searches will be performed on MEDLINE, CINAHL, PsycINFO, Web of Knowledge, ProQuest Thesis&Dissertations and grey literature and will be focused on questionnaires measuring patient comfort as a holistic experience in any healthcare setting. The assessment will take into account the theoretical model on which the instruments are built, evaluate the psychometric properties of each study according to the COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) and will include the assessment of the quality of instruments outcomes and their cost-efficiency, acceptability and educational impact. The review protocol was registered in PROSPERO, CRD42016036290 and was supported by the Grant PSI2014-52962-P, Spanish Ministry of Economy and Competitiveness (July, 2015). DISCUSSION The results of our psychometric review will categorise the instruments measuring the patient comfort according to their psychometric properties, methodological quality, outcomes and utility, to improve the quality of health care provided and the institutions benefits.

Three risk of bias tools lead to opposite conclusions in observational research synthesis

OBJECTIVES The aim of this study was to assess the agreement and compare the performance of three different instruments in assessing risk of bias (RoB) of comparative cohort studies included in a health psychology meta-analysis. STUDY DESIGN AND SETTING Three tools were applied to 28 primary studies included in the selected meta-analysis: the Newcastle-Ottawa Scale, quality of cohort studies (Q-Coh), and risk of bias in nonrandomized studies of interventions (ROBINS-I). RESULTS Interrater agreement varied greatly from tool to tool. For overall RoB, 75% of the studies were rated as low RoB with the Newcastle-Ottawa Scale, 11% of the studies with Q-Coh, and no study was found to be at low RoB using ROBINS-I. No influence of quality ratings on the meta-analysis results was found for any of the tools. CONCLUSION Assessing RoB using the three tools may lead to opposite conclusions, especially at low and high levels of RoB. Domain-based tools (Q-Coh and ROBINS-I) provide a more comprehensive framework for identifying potential sources of bias, which is essential to improving the quality of future research. Both further guidance on the application of RoB tools and improvements in the reporting of primary studies are necessary.

Instruments to assess patient comfort during hospitalization: A psychometric review.

AIM To analyse the psychometric properties and the utility of instruments used to measure patient comfort, physical, social, psychospiritual and/or environmental, during hospitalization. BACKGROUND There are no systematic reviews nor psychometric reviews of instruments used to measure comfort, which is considered an indicator of quality in health care associated with quicker discharges, increased patient satisfaction and better cost-benefit ratios for the institution. DESIGN Psychometric review. DATA SOURCES MEDLINE, CINAHL, PsycINFO, Web of Knowledge, ProQuest Thesis&Dissertations, Google. REVIEW METHODS We limited our search to studies published between 1990-2015. The psychometric analysis was performed using the COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN), along with the Quality Criteria for Measurement Properties. The utility of the instruments was assessed according to their cost-efficiency, acceptability and educational impact. Protocol registration in PROSPERO, CRD42016036290. RESULTS Instruments reviewed showed moderate methodological quality and their utility was poorly reported. Thus, we cannot recommend any questionnaire without reservations, but the Comfort Scale, the General Comfort Questionnaire and their adaptations in adults and older patients, the Psychosocial Comfort Scale and the Incomfort des Patients de Reanimation are the most recommendable instruments to measure comfort. CONCLUSIONS The methodology of the studies should be more rigorous and authors should adequately report the utility of instruments. This review provides a strategy to select the most suitable instrument to assess patient comfort according to their psychometric properties and utility, which is crucial for nurses, clinicians, researchers and institutions.

Tools to assess the measurement properties of quality of life instruments: a meta-review protocol

Introduction Using specific tools to assess the measurement properties of health status instruments is recommended both to standardise the review process and to improve the methodological quality of systematic reviews. However, depending on the measurement standards on which these tools are developed, the approach to appraise the measurement properties of instruments may vary. For this reason, the present meta-review aims to: (1) identify systematic reviews assessing the measurement properties of instruments evaluating health-related quality of life (HRQoL); (2) identify the tools applied to assess the measurement properties of HRQoL instruments; (3) describe the characteristics of the tools applied to assess the measurement properties of HRQoL instruments; (4) identify the measurement standards on which these tools were developed or conform to and (5) compare the similarities and differences among the identified measurement standards. Methods and analysis A systematic review will be conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols Guidelines. Electronic search will be carried out on bibliographic databases, including PubMed, Cumulative Index to Nursing and Allied Health Literature, Psychological Information, SCOPUS, Web of Science, COSMIN database and ProQuest Dissertations & Theses Global, being limited by time (2008–2018) and language (English). Descriptive analyses of different aspects of tools applied to evaluate the measurement properties of HRQoL instruments will be presented; the different measurement standards will be described and some recommendations about the methodological and research applications will be made. Ethics and dissemination Ethical approval is not necessary for systematic review protocols. The results will be disseminated by its publication in a peer-reviewed journal and presented at a relevant conference. PROSPERO registration number CRD42017065232