http://nova.newcastle.edu.au/vital/access/services/Feed ${session.getAttribute("locale")} 5 http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10523 Objectives: To identify and summarize the existing literature on domains/items of health-relatedquality of life (HRQoL) that are important for patients with knee or hip osteoarthritis (OA) in various sociocultural contexts and critically evaluate existing OA-specific HRQoL instruments based on the importantdomains/items identified. Methods: A qualitative systematic literature review was performed using (1) an electronic search of Medline, PsycINFO, ISI Web of Knowledge, and the Cochrane Library (using 29 relevant keywords), and (2) a manual search of relevant journals, textbooks, and bibliographies. Titles and abstracts were reviewed using predefined criteria to select potential articles for full text review. Results: From 20,768 reviewed references, 77 articles were selected for full text review, of which 15 articles fulfilled inclusion criteria. Studies were conducted in English (4 each in the United States and Canada, 2 in the United Kingdom, and 1 in Ireland), French (n = 2), and Swedish (n = 2). Important HRQoL domains in 1 or more countries included pain, physical disability, sports/recreational activities, other symptoms of OA, mental health, social health, and knee/hip-relatedquality of life. Items within each domain varied from country to country except some physical disability items. The paucity of available information did not allow adequate assessment of OA-specific instruments’ coverage of important domains/items in various sociocultural contexts. Conclusions: A surprisingly sparse literature reports the important HRQoL domains/items from the perspective of patients with knee or hip OA. Additional studies are needed to determine the importantdomains/items for these patients and to confirm that OA-specific measures are truly accurate and comprehensive when applied in various sociocultural contexts. 2012-03-26T04:20:07.718Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10524 Objective: To evaluate content validity and construct validity of the International Classification of Functioning, Disability and Health (ICF) Comprehensive Core Set for Osteoarthritis (OA) in Singapore. Methods: Patients with knee OA completed case report forms, which included the SF-36, Self-administered Comorbidity Questionnaire (SCQ), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Health professionals completed the ICF Comprehensive Core Set for OA. Content validity was evaluated using frequency and percentage of patients with a reported problem for each ICF category, while construct validity was evaluated using Spearman correlation between the ICF categories and SF-36 and the WOMAC. Results: A consecutive sample of 122 patients completed this study. In body functions, 12 categories were documented as a problem by more than 10% of the patients, of which 7, 12, and 10 categories correlated significantly with the SF-36 Physical Component Summary (PCS), WOMAC pain, and physical function, respectively. Only s750 (Structure of lower extremity) in body structures was reported as a problem and correlated significantly with SF-36 and WOMAC. In activities and participation, 12 categories were reported as a problem by more than 10% of the patients, of which, 11, 11, and 12 correlated significantly with SF-36 PCS, WOMAC pain, and physical function, respectively. In environmental factors, 2 and 1.4 categories were documented as barrier and facilitator, respectively, by more than 10% of the patients, but none correlated significantly with SF-36 and WOMAC. Conclusion: The content and construct validity of the Comprehensive Core Set for OA could be supported. Some categories, especially in environmental factors, need to be studied further in different sociocultural contexts. 2012-03-26T04:20:04.363Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5747 Background: Symbols have been used in health state valuation studies to help subjects distinguish the severity of various characteristics of a given health state. Symbols used in such studies need to be evaluated for their cross-cultural appropriateness because a given symbol may have different meanings or acceptability in different cultures, which may affect results of such studies. Objectives: To evaluate if using symbols to differentiate health states of different severity is useful and culturally acceptable in a multi-ethnic, urban Asian population. Methods: Using in-depth interviews with adult Chinese, Malay, and Indian Singaporeans conducted in English/mother-tongue, subjects were shown a health state with 6 levels (Health Utilities Index 3 vision), each displayed with a symbol, and asked (1a) if symbols were useful in differentiating severity of each level (measured using dichotomous and 0–10 visual analog scale [VAS] scales) or (1b) offensive and (2) to assess 7 alternative sets of symbols. Results: Of 63 subjects (91% response rate), 18 (29%) felt symbols were useful in differentiating severity of each level. Reported usefulness of symbols was fair (median VAS score: 3.0, score exceeding 5.0 for 33% of subjects). One Malay subject felt symbols were offensive. Conclusions: Use of symbols for health state valuation was culturally acceptable and useful for some subjects. 2012-01-30T04:05:32.593Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5443 Objective: To assess the psychometric properties of the Schizophrenia Quality of Life Scale (SQLS) in Asians with schizophrenia in Singapore. Methods: A consecutive sample of outpatients with schizophrenia completed the English or Chinese version of the SQLS and the Short-Form 36 Health Survey (SF-36) twice during two different clinic visits. The patients were also assessed for presence or absence of 22 psychiatric symptoms. Results: About 202 patients (English-speaking: 140) participated in the study. Correlations between SQLS scales and other measures assessing similar constructs ranged from 0.46 to 0.69 (P < 0.001 for all). For SQLS psychosocial and symptoms/side effects scales, item-to-scale correlations were >0.4, Cronbach’s alpha and intra-class correlation coefficient values were close to or exceed 0.7, and Cohen’s effect size, standardized response mean, and Guyatt’s responsiveness index values approximated or exceeded 0.2 for both SQLS language versions; however, for the energy/motivation scale, item-to-scale correlations (range: 0.08–0.51), reliability (range: 0.46–0.66) and responsiveness (range: 0.04–0.08) statistics were not satisfactory for both SQLS versions. Conclusions: The SQLS psychosocial and symptoms/side effects scales are valid, reliable and responsive in Singaporean patients with schizophrenia; the appropriateness of energy/motivation scale requires further investigation. 2010-04-27T04:48:07.627Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5182 Objectives: To estimate indirect costs through human capital approach and intangible costs through willingness-to-pay (WTP), and identify factors potentially affecting these costs in multiethnic Asian patients with knee osteoarthritis (OA). Methods: Data were collected through face-to-face interviews among knee OA patients. Human capital approach was used to estimate indirect costs by multiplying: 1) days of absence from work because of OA, with average earnings per capita per day for working patients; or 2) productivity loss with the market price of housekeeping for retirees/homemakers. A closed-ended iterative bidding contingent valuation method was used to elicit willingness-to-pay for a hypothetical cure of OA as a proxy for intangible costs. Mann-Whitney U or Kruskal-Wallis H-tests were performed in univariate analyzes, and linear regression in multivariate analyses. Results: Indirect costs per year and intangible costs were estimated at US$1.008 and US$1200, accounting for 2.8% and 3.3% of annual household income, respectively. The indirect costs were significantly higher for male or working patients, while intangible costs were higher for Chinese, working patients, with higher income, or worse global well-being. Conclusion: This study demonstrated that eliciting indirect costs through human capital approach and intangible costs through WTP are acceptable and feasible in Asian patients with knee OA. Besides the direct costs, the indirect and intangible costs for the OA patients could be substantial. 2010-04-27T04:46:46.219Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5185 Objective: Our aim was to cross-culturally validate Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in patients with knee osteoarthritis (OA) scheduled for total knee replacement in Singapore. Methods: Chinese WOMAC was translated from the original English version following standard guidelines. Patients were asked to complete a questionnaire containing the WOMAC (twice within 6 days), the Short Form 36 (SF-36), and the EuroQoL EQ-5D. Reliability was assessed using Cronbach's alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations and factor analyses. Convergent and discriminant construct validity was assessed using six each a priori hypotheses. Results: Chinese WOMAC was well accepted by the patients in the pilot test. The Chinese and English versions were therefore administered to a consecutive sample of 131 Chinese- and 127 English-speaking subjects, respectively, with knee OA. Cronbach's alpha exceeded 0.7 for all domains except for Chinese pain domain, whereas the ICC exceeded 0.7 for all domains. Hypothesized item-to-domain correlations were observed for all items except for four items in Chinese physical function domain. The factor analyses yielded seven and five factors with eigenvalues of more than 1.0 in the Chinese and English versions, respectively. A total of 10/12 a priori construct validity hypotheses were satisfied for the Chinese version. Weak correlations between WOMAC pain and SF-36 bodily pain and moderate correlation between WOMAC pain and EQ-5D anxiety/depression were observed. Conclusions: Chinese WOMAC was well accepted and demonstrated acceptable psychometric properties in Singaporean patients with severe knee OA. 2010-04-27T04:46:42.537Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5027 Objectives: Expectancy-Value Model (EVM) is the most structured model in psychology to predict attitudes by measuring attitudinal attributes (AAs) and relevant external variables. Because health value could be categorized as attitude, we aimed to apply EVM to explore its usefulness in explaining variances in health values and investigate underlying factors. Methods: Focus group discussion was carried out to identify the most common and significant AAs toward 5 different health states (coded as 11111, 11121, 21221, 32323, and 33333 in EuroQol Five-Dimension (EQ-5D) descriptive system). AAs were measured in a sum of multiplications of subjective probability (expectancy) and perceived value of attributes with 7-point Likert scales. Health values were measured using visual analog scales (VAS, range 0–1). External variables (age, sex, ethnicity, education, housing, marital status, and concurrent chronic diseases) were also incorporated into survey questionnaire distributed by convenience sampling among eligible respondents. Univariate analyses were used to identify external variables causing significant differences in VAS. Multiple linear regression model (MLR) and hierarchical regression model were used to investigate the explanatory power of AAs and possible significant external variable(s) separately or in combination, for each individual health state and a mixed scenario of five states, respectively. Results: Four AAs were identified, namely, "worsening your quality of life in terms of health" (WQoL), "adding a burden to your family" (BTF), "making you less independent" (MLI) and "unable to work or study" (UWS). Data were analyzed based on 232 respondents (mean [SD] age: 27.7 [15.07] years, 49.1% female). Health values varied significantly across 5 health states, ranging from 0.12 (33333) to 0.97 (11111). With no significant external variables identified, EVM explained up to 62% of the variances in health values across 5 health states. The explanatory power of 4 AAs were found to be between 13% and 28% in separate MLR models (P < 0.05). When data were analyzed for each health state, variances in health values became small and explanatory power of EVM was reduced to a range between 8% and 23%. Conclusion: EVM was useful in explaining variances of health values and predicting important factors. Its power to explain small variances might be restricted due to limitations of 7-point Likert scale to measure AAs accurately. With further improvement and validation of a compatible continuous scale for more accurate measurement, EVM is expected to explain health values to a larger extent. 2010-04-27T04:45:32.551Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5336 Objectives: To assess the validity, feasibility and acceptability of standard gamble (SG) and time trade-off (TTO) assessments in a multiethnic Asian population. Methods: Through in-depth interviews performed among Chinese, Malay, and Indian Singaporeans (education ≥ 6 years), we assessed validity of SG/TTO methods for eliciting health preferences by hypothesizing that 1) SG/TTO scores for three hypothetical health states (HS) would exhibit ranked order (decreasing scores with worse HS); and 2) more subjects would rate the most severe HS as worse than dead. Subjects also evaluated feasibility and acceptability of SG/TTO using a 10-point visual analog scale (VAS) and open-ended questions. Ratings were compared using Kruskal-Wallis, Wilcoxon signed-rank tests or tests of proportions. Results: Validity: In 62 subjects (90% response rate), as hypothesized, SG and TTO scores exhibited ranked order with increasing HS severity (SG: 0.85, 0.08, -19.00; TTO: 0.85, 0.00, -0.18). More subjects rated the most severe HS as worse than dead (SG: 8%, 39%, 59%; TTO: 8%, 45% and 62%). Feasibility: Subjects felt SG and TTO were easy to understand (median VAS scores: 8.0 vs. 8.0, P = 0.87) and to complete (8.0 vs. 8.0, P = 0.84). Acceptability: SG and TTO were well accepted, with TTO less so than SG (median [interquartile range] offensiveness: 2.0 [0, 4.0] vs. 2.0 [0, 3.0], P = 0.045). Overall, subjects did not have a clear preference for SG/TTO (50% vs. 45%, P = 0.70). Conclusions: This study suggests the validity, feasibility and acceptability of SG and TTO for population-based HS valuation studies in a multiethnic Asian population. 2010-04-27T04:30:36.525Z ]]>