Project description:BackgroundMSQOL-54 is a multidimensional, widely-used, health-related quality of life (HRQOL) instrument specific for multiple sclerosis (MS). Findings from the validation study suggested that the two MSQOL-54 composite scores are correlated. Given this correlation, it could be assumed that a unique total score of HRQOL may be calculated, with the advantage to provide key stakeholders with a single overall HRQOL score. We aimed to assess how well the bifactor model could account for the MSQOL-54 structure, in order to verify whether a total HRQOL score can be calculated.MethodsA large international database (3669 MS patients) was used. By means of confirmatory factor analysis, we estimated a bifactor model in which every item loads onto both a general factor and a group factor. Fit of the bifactor model was compared to that of single and two second-order factor models by means of Akaike information and Bayesian information criteria reduction. Reliability of the total and subscale scores was evaluated with Mc Donald's coefficients (omega, and omega hierarchical).ResultsThe bifactor model outperformed the two second-order factor models in all the statistics. All items loaded satisfactorily (≥ 0.40) on the general HRQOL factor, except the sexual function items. Omega coefficients for total score were very satisfactory (0.98 and 0.87). Omega hierarchical for subscales ranged between 0.22 to 0.57, except for the sexual function (0.70).ConclusionsThe bifactor model is particularly useful when it is intended to acknowledge multidimensionality and at the same time take account of a single general construct, as the HRQOL related to MS. The total raw score can be used as an estimate of the general HRQOL latent score.
Project description:There is evidence that models of psychopathology specifying a general factor and specific second-order factors fit better than competing structural models. Nonetheless, additional tests are needed to examine the generality and boundaries of the general factor model. In a selected second wave of a cohort study, first-order dimensions of psychopathology symptoms in 499 23- to 31-year-old twins were analyzed. Using confirmatory factor analysis, a bifactor model specifying a general factor and specific internalizing and externalizing factors fit better than competing models. Factor loadings in this model were sex invariant despite greater variances in the specific internalizing factor among females and greater variances in the general and specific externalizing factors among males. The bifactor structure was robust to the exclusion of any single first-order dimension of psychopathology. Furthermore, the results were essentially unchanged when all overlapping symptoms that define multiple disorders were excluded from symptom dimensions. Furthermore, the best-fitting bifactor model also emerged in exploratory structural equation modeling with freely estimated cross-loadings. The general factor of psychopathology was robust across variations in measurement and analysis.
Project description:Purpose. To present the psychometric properties of a new measure of quality of life in older age, the Older People's Quality of Life (OPQOL) Questionnaire, compared with the CAPSE-19 and the WHOQOL-OLD. Design and Methods. The vehicle was three national population surveys of older people living at home in Britain, including a survey of ethnically diverse older people. Results. The OPQOL had acceptable levels of reliability and validity in British population samples of older people, but more modest in the ethnically diverse population sample. The CASP-19 and WHOQOL-OLD had acceptable levels of reliability and validity in the British population sample, but not in the ethnically diverse sample. Implications. The OPQOL has potential for use as a multidimensional population surveillance instrument for use with older populations, or as an outcome measure of multisector policy. Its strengths are that its development was embedded firmly in the perspectives of older people, integrated with theory.
Project description:BackgroundIt is important to obtain greater insight into health-related quality of life (HRQL) of injury patients in order to document people's pathways to recovery and to quantify the impact of injury on population health over time. We performed a systematic review of studies measuring HRQL in general injury populations with a generic health state measure to summarize existing knowledge.MethodsInjury studies (1995-2009) were identified with main inclusion criteria being the use of a generic health status measure and not being restricted to one specific type of injury. Articles were collated by study design, HRQL instrument used, timing of assessment(s), predictive variables and ability to detect change over time.ResultsForty one studies met inclusion criteria, using 24 different generic HRQL and functional status measures (most used were SF-36, FIM, GOS, EQ-5D). The majority of the studies used a longitudinal design, but with different lengths and timings of follow-up (mostly 6, 12, and 24 months). Different generic health measures were able to discriminate between the health status of subgroups and picked up changes in health status between discharge and 12 month follow-up. Most studies reported high prevalences of health problems within the first year after injury. The twelve studies that reported HRQL utility scores showed considerable but incomplete recovery in the first year after discharge.ConclusionThis systematic review demonstrates large variation in use of HRQL instruments, study populations, and assessment time points used in studies measuring HRQL of general injury populations. This variability impedes comparison of HRQL summary scores between studies and prevented formal meta-analyses aiming to quantify and improve precision of the impact of injury on population health over time.
Project description:Although the factor structure of psychosis continues to be debated by taxonomists, recent studies have supported a bifactor model consisting of a general psychosis factor and 5 uncorrelated symptom-specific factors. While this model has received support in clinical samples, it has not been tested at the general population level. Analysis was conducted on Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (N = 34 653). Twenty-two psychotic symptoms were used as observed indicators of psychosis. These items were chosen based on their conceptual similarity to the items used in a similar study based on clinical samples. Confirmatory factor analysis and confirmatory bifactor modeling were used to test a variety of competing models. The best fitting model consisted of a general psychosis factor that was uncorrelated with 5 specific factors: positive, negative, disorganization, mania, and depression. These findings suggest that the bifactor model can be extended to general population samples, supporting the continuity between clinical and subclinical psychotic experiences. Theoretical and practical implications are discussed.
Project description:ObjectivesThe objectives of this study were to develop a conceptual model of quality of life (QOL) in muscular dystrophies (MDs) and review existing QOL measures for use in the MD population.MethodsOur model for QOL among individuals with MD was developed based on a modified Delphi process, literature review, and input from patients and patient advocacy organizations. Scales that have been used to measure QOL among patients with MD were identified through a literature review and evaluated using the COSMIN (Consensus-Based Standards for the Selection of Health Measurement Instruments) checklist.ResultsThe Comprehensive Model of QOL in MD (CMQM) captures 3 broad domains of QOL (physical, psychological, and social), includes factors influencing self-reported QOL (disease-related factors, support/resources, and expectations/aspirations), and places these concepts within the context of the life course. The literature review identified 15 QOL scales (9 adult and 6 pediatric) that have been applied to patients with MD. Very few studies reported reliability data, and none included data on responsiveness of the measures to change in disease progression, a necessary psychometric property for measures included in treatment and intervention studies. No scales captured all QOL domains identified in the CMQM model.ConclusionsAdditional scale development research is needed to enhance assessment of QOL for individuals with MD. Item banking and computerized adaptive assessment would be particularly beneficial by allowing the scale to be tailored to each individual, thereby minimizing respondent burden.
Project description:The University of Queensland Quality of Life instrument (UQQoL) was developed to provide a quantitative measure sensitive to the impact of increased exercise on the quality of life (QoL) of older individuals. This paper describes the development and testing of the UQQoL including an exploratory study of focus group interviews with 18 participants aged 65 and over, item development and selection, and instrument piloting with groups of older adults undergoing high-intensity training. The SF-36, another established QoL tool, was also administered at the same time points for comparative purposes. The UQQoL displayed good convergent validity with selected SF-36 domains. A significant change in QoL following training was found, complementing functional improvements. This change was not detected by the SF-36. While broader testing is required, the UQQoL appears to be a reliable instrument sensitive to the change in QoL experienced by healthy community-dwelling older adults following resistance exercise.
Project description:BACKGROUND:Domains other than those commonly measured (physical, psychological, social, and sometimes existential/spiritual) are important to the quality of life of people with life-threatening illness. The McGill Quality of Life Questionnaire (MQOL) - Revised measures the four common domains. The aim of this study was to create a psychometrically sound instrument, MQOL - Expanded, to comprehensively measure quality of life by adding to MQOL-Revised the domains of cognition, healthcare, environment, (feeling like a) burden, and possibly, finance. METHODS:Confirmatory factor analyses were conducted on three datasets to ascertain whether seven new items belonged with existing MQOL-Revised domains, whether good model fit was obtained with their addition as five separate domains to MQOL-Revised, and whether a second-order factor representing overall quality of life was present. People with life-threatening illnesses (mainly cancer) or aged > 80 were recruited from 15 healthcare sites in seven Canadian provinces. Settings included: palliative home care and inpatient units; acute care units; oncology outpatient clinics. RESULTS:Good model fit was obtained when adding each of the five domains separately to MQOL-Revised and for the nine correlated domains. Fit was acceptable for a second-order factor model. The financial domain was removed because of low importance. The resulting MQOL-Expanded is a 21-item instrument with eight domains (fit of eight correlated domains: Comparative Fit Index = .96; Root Mean Square Error of Approximation = .033). CONCLUSIONS:MQOL-Expanded builds on MQOL-Revised to more comprehensively measure the quality of life of people with life-threatening illness. Our analyses provide validity evidence for the MQOL-Expanded domain and summary scores; the need for further validation research is discussed. Use of MQOL-Expanded will enable a more holistic understanding of the quality of life of people with a life-threatening illness and the impact of treatments and interventions upon it. It will allow for a better understanding of less commonly assessed but important life domains (cognition, healthcare, environment, feeling like a burden) and their relationship to the more commonly assessed domains (physical, psychological, social, existential/spiritual).
Project description:BackgroundProstate cancer (PCa) represents the most common solid organ malignancy in men. Fortunately, at the time of diagnosis, the majority of cases are staged as localized or regional disease, conferring excellent 5- and 10-year cure rates. There are several first line treatment options including surgical approaches such as robot-assisted radical prostatectomy (RARP) and radiation therapy (RT) available to patients with localized disease that offer similar PCa oncologic outcomes but are associated with potentially significant side effects which may impact health-related quality of life (HRQOL) domains. Recently, clinicians and investigators have sought to better understand these changes in HRQOL metrics with the utilization of patient-reported outcomes (PRO). Given that RARP represents the most common surgical treatment for PCa in the United States, there has been a particular interest in assessing these outcomes derived by patient perspectives to more fully appreciate treatment-related impact on quality of life following RARP.ObjectiveThis narrative review sought to explore the instruments available to measure quality of life after RARP, a review of the PRO data after RARP, and future directions for assessing and improving quality of life outcomes following this surgery.Clinical useThere are several treatment options for men diagnosed with local and regional prostate cancer with similar oncologic outcomes but differing patterns of side effects affecting post-treatment quality of life. Understanding data reported directly by patients following RARP about their side effects and quality of life gives providers additional information for appropriate preoperative counseling for patients choosing between treatment options for their prostate cancer.