Variation in the apparent importance of health-related problems with the instrument used to measure patient welfare.

AIMS: This paper investigates the distributional implications for eight population groups of using six different instruments to measure wellbeing and to prioritise access to health services. Specifically, it examines the importance of different physical and psycho-social problems for the scores obtained using each instrument and whether scores differ because of differences in the concept measured by the instrument or because of the instrument's construction. METHODS: Patients with seven chronic conditions and a sample of the 'healthy' public were administered six instruments: two utility instruments; two self-rating scales; a subjective wellbeing instrument and the ICECAP measure of capability. Scores were regressed upon the subscales of the SF-36 and the AQoL-8D. Each instrument's 'problem mix' was measured by the numerical importance of the subscales for the instrument's score and compared with the problem mix of patients constructed from all of the instruments. RESULTS: The apparent importance of different problems varied significantly with the instrument used to assess welfare but not with the chronic conditions. The correspondence between an instrument's problem mix and the patients' problem mix was highly variable. CONCLUSION: Different instruments give prominence to different physical and psycho-social problems and consequently favour different groups of patients. Budgetary decisions which appear to be based on efficiency criteria such as the cost per quality-adjusted life year (QALY) conceal distributive effects attributable to the instrument used in the analysis. The effects are additional to the ethical questions considered in making an equity-efficiency trade-off as they arise from the measurement of efficiency.

Why do multi-attribute utility instruments produce different utilities: the relative importance of the descriptive systems, scale and 'micro-utility' effects.

PURPOSE: Health state utilities measured by the major multi-attribute utility instruments differ. Understanding the reasons for this is important for the choice of instrument and for research designed to reconcile these differences. This paper investigates these reasons by explaining pairwise differences between utilities derived from six multi-attribute utility instruments in terms of (1) their implicit measurement scales; (2) the structure of their descriptive systems; and (3) 'micro-utility effects', scale-adjusted differences attributable to their utility formula. METHODS: The EQ-5D-5L, SF-6D, HUI 3, 15D and AQoL-8D were administered to 8,019 individuals. Utilities and unweighted values were calculated using each instrument. Scale effects were determined by the linear relationship between utilities, the effect of the descriptive system by comparison of scale-adjusted values and 'micro-utility effects' by the unexplained difference between utilities and values. RESULTS: Overall, 66 % of the differences between utilities was attributable to the descriptive systems, 30.3 % to scale effects and 3.7 % to micro-utility effects. DISCUSSION: Results imply that the revision of utility algorithms will not reconcile differences between instruments. The dominating importance of the descriptive system highlights the need for researchers to select the instrument most capable of describing the health states relevant for a study. CONCLUSIONS: Reconciliation of inconsistent utilities produced by different instruments must focus primarily upon the content of the descriptive system. Utility weights primarily determine the measurement scale. Other differences, attributable to utility formula, are comparatively unimportant.

Assessing outcomes for cost-utility analysis in depression: comparison of five multi-attribute utility instruments with two depression-specific outcome measures.

BACKGROUND: Many mental health surveys and clinical studies do not include a multi-attribute utility instrument (MAUI) that produces quality-adjusted life-years (QALYs). There is also some question about the sensitivity of the existing utility instruments to mental health. AIMS: To compare the sensitivity of five commonly used MAUIs (Assessment of Quality of Life - Eight Dimension Scale (AQoL-8D), EuroQoL-five dimension (EQ-5D-5L), Short Form 6D (SF-6D), Health Utilities Index Mark 3 (HUI3), 15D) with that of disease-specific depression outcome measures (Depression Anxiety Stress Scales (DASS-21) and the Kessler Psychological Distress Scale (K10)) and develop 'crosswalk' transformation algorithms between the measures. METHOD: Individual data from 917 people with self-report depression collected as part of the International Multi-Instrument Comparison Survey. RESULTS: All the MAUIs discriminated between the levels of severity measured by the K10 and the DASS-21. The AQoL-8D had the highest correlation with the disease-specific measures and the best goodness-of-fit transformation properties. CONCLUSIONS: The algorithms developed in this study can be used to determine cost-effectiveness of services or interventions where utility measures are not collected.

An instrument for measuring the social willingness to pay for health state improvement.

This paper describes an instrument for measuring the social value of changes in health status, the Relative Social Willingness to Pay. It is a unique combination of measurement attributes designed to minimise cognitive complexity and provide an additional option for measuring 'social value'. Similar to the person trade-off (PTO), it adopts a social perspective and asks respondents to evaluate programmes on behalf of society. Unlike the PTO, trade-offs between the options use dollars, not numbers of patients. Respondents are not, however, asked for their personal willingness to pay. Rather, the opportunity cost of funds spent on one service is as an offsetting reduction in funds for a second service. The amount spent on each service therefore indicates relative, not absolute, value. However, the two services combine to produce one Quality adjusted life year which allows the calculation of a Quality adjusted life year-like unit of social value on a 0-1 scale. A three-stage survey was used to test the instrument's reliability, validity and sensitivity to the framing of the main question. Results indicate that the Relative Social Willingness to Pay produces values similar to but less than the PTO and time trade-off techniques.

Modelling utility weights for the Assessment of Quality of Life (AQoL)-8D.

PURPOSE: The objective of this paper is to describe the four-stage methodology used to obtain utility scores for the Assessment of Quality of Life (AQoL)-8D, a 35-item 8 dimension multi-attribute utility instrument, which was created to achieve a high degree of sensitivity to psycho-social health. METHODS: Data for the analyses were obtained from a representative group of 347 members of the Australian public and from 323 mental health patients each of whom provided VAS and time trade-off valuations of multiple health states. Data were used initially to create multiplicative scoring algorithms for each of the instrument's 8 dimensions and for the overall instrument. Each of the algorithms was then subject to a second-stage econometric 'correction'. RESULTS: Algorithms were successfully created for each of the AQoL-8D's dimensions, for physical and mental 'super-dimensions' and for the overall AQoL-8D instrument. The final AQoL-8D algorithm has good predictive power with respect to the TTO valuations. CONCLUSIONS: The AQoL-8D is a suitable instrument for researchers conducting cost utility analyses generally but, in particular, for the analysis of services affecting psycho-social health.

A Systematic Review of Whether the Use of N95 Respirator Masks Decreases the Incidence of Cardiovascular Disease in the General Population.

The usage of masks such as the N95 has increased exponentially worldwide. With the ever-increasing global rates of cardiovascular disease, it is vital that preventative measures are adopted to help tackle this crisis. N95 masks have been promoted as health prevention odysseys in the battle against viruses such as COVID-19. A systematic review was conducted on whether the N95 masks could help improve our cardiovascular health. Our data sources included PubMed, Medline and Scopus. Eleven studies met the eligibility criteria to be included in the review. N95 mask usage led to increased reports of dyspnoea, however, no significant effect was seen on blood pressure. N95 masks also showed improvement in aortic parameters. While encouraging results were yielded, further focussed studies on the use of N95 masks and the effect on various cardiovascular parameters would help strengthen the association.

Meta-analysis of skin adhesives versus sutures in closure of laparoscopic port-site wounds.

OBJECTIVE: To analyze the effectiveness of skin adhesives and sutures in the closure of laparoscopic port-site wounds. METHODS: Electronic databases were searched to find relevant randomized controlled trials and their data was analyzed to generate a summative outcome. RESULTS: Seven trials on port-site wound closure after laparoscopic procedures encompassing 902 patients were retrieved from the electronic databases. Four randomized controlled trials on 404 patients qualified for the review according to inclusion criteria. In both fixed- and random-effects models, there was no difference between the two port-site wound closure techniques in terms of wound infection, wound dehiscence and, patient satisfaction. However, statistically tissue adhesives were quicker in port-site wound closure as compared with sutures. CONCLUSIONS: Based on this review, there is insufficient evidence that port-site wound closure technique by tissue adhesives is superior to traditional suture closure technique in terms of wound infection, wound dehiscence, and patient satisfaction. However, tissue adhesives are quicker in port-site wound closure. A multicentre randomized controlled trial is required in order to obtain stronger evidence.

Measuring the Sensitivity and Construct Validity of 6 Utility Instruments in 7 Disease Areas.

BACKGROUND: Health services that affect quality of life (QoL) are increasingly evaluated using cost utility analyses (CUA). These commonly employ one of a small number of multiattribute utility instruments (MAUI) to assess the effects of the health service on utility. However, the MAUI differ significantly, and the choice of instrument may alter the outcome of an evaluation. AIMS: The present article has 2 objectives: 1) to compare the results of 3 measures of the sensitivity of 6 MAUI and the results of 6 tests of construct validity in 7 disease areas and 2) to rank the MAUI by each of the test results in each disease area and by an overall composite index constructed from the tests. METHODS: Patients and the general public were administered a battery of instruments, which included the 6 MAUI, disease-specific QoL instruments (DSI), and 6 other comparator instruments. In each disease area, instrument sensitivity was measured 3 ways: by the unadjusted mean difference in utility between public and patient groups, by the value of the effect size, and by the correlation between MAUI and DSI scores. Content and convergent validity were tested by comparison of MAUI utilities and scores from the 6 comparator instruments. These included 2 measures of health state preferences, measures of subjective well-being and capabilities, and generic measures of physical and mental QoL derived from the SF-36. RESULTS: The apparent sensitivity of instruments varied significantly with the measurement method and by disease area. Validation test results varied with the comparator instruments. Notwithstanding this variability, the 15D, AQoL-8D, and the SF-6D generally achieved better test results than the QWB and EQ-5D-5L.

Mapping between 6 Multiattribute Utility Instruments.

BACKGROUND: Cost-utility analyses commonly employ a multiattribute utility (MAU) instrument to estimate the health state utilities, which are needed to calculate quality-adjusted life years. Different MAU instruments predict significantly different utilities, which makes comparison of results from different evaluation studies problematical. AIM: This article presents mapping functions ("crosswalks") from 6 MAU instruments (EQ-5D-5L, SF-6D, Health Utilities Index 3 [HUI 3], 15D, Quality of Well-Being [QWB], and Assessment of Quality of Life 8D [AQoL-8D]) to each of the other 5 instruments in the study: a total of 30 mapping functions. METHODS: Data were obtained from a multi-instrument comparison survey of the public and patients in 7 disease areas conducted in 6 countries (Australia, Canada, Germany, Norway, United Kingdom, and United States). The 8022 respondents were administered each of the 6 study instruments. Mapping equations between each instrument pair were estimated using 4 econometric techniques: ordinary least squares, generalized linear model, censored least absolute deviations, and, for the first time, a robust MM-estimator. RESULTS: Goodness-of-fit indicators for each of the results are within the range of published studies. Transformations reduced discrepancies between predicted utilities. Incremental utilities, which determine the value of quality-related health benefits, are almost perfectly aligned at the sample means. CONCLUSION: Transformations presented here align the measurement scales of MAU instruments. Their use will increase confidence in the comparability of evaluation studies, which have employed different MAU instruments.

Diabetes and quality of life: Comparing results from utility instruments and Diabetes-39.

OBJECTIVE: To compare the Diabetes-39 (D-39) with six multi-attribute utility (MAU) instruments (15D, AQoL-8D, EQ-5D, HUI3, QWB, and SF-6D), and to develop mapping algorithms which could be used to transform the D-39 scores into the MAU scores. RESEARCH DESIGN AND METHODS: Self-reported diabetes sufferers (N=924) and members of the healthy public (N=1760), aged 18 years and over, were recruited from 6 countries (Australia 18%, USA 18%, UK 17%, Canada 16%, Norway 16%, and Germany 15%). Apart from the QWB which was distributed normally, non-parametric rank tests were used to compare subgroup utilities and D-39 scores. Mapping algorithms were estimated using ordinary least squares (OLS) and generalised linear models (GLM). RESULTS: MAU instruments discriminated between diabetes patients and the healthy public; however, utilities varied between instruments. The 15D, SF-6D, AQoL-8D had the strongest correlations with the D-39. Except for the HUI3, there were significant differences by gender. Mapping algorithms based on the OLS estimator consistently gave better goodness-of-fit results. The mean absolute error (MAE) values ranged from 0.061 to 0.147, the root mean square error (RMSE) values 0.083 to 0.198, and the R-square statistics 0.428 and 0.610. Based on MAE and RMSE values the preferred mapping is D-39 into 15D. R-square statistics and the range of predicted utilities indicate the preferred mapping is D-39 into AQoL-8D. CONCLUSIONS: Utilities estimated from different MAU instruments differ significantly and the outcome of a study could depend upon the instrument used. The algorithms reported in this paper enable D-39 data to be mapped into utilities predicted from any of six instruments. This provides choice for those conducting cost-utility analyses.

Can multi-attribute utility instruments adequately account for subjective well-being?

INTRODUCTION: The quality of life is included in cost utility analyses by weighting the relevant years of life by health state utilities. However, the utilities predicted by multi-attribute utility instruments (MAUIs) for this purpose do not correlate highly with the subjective well-being (SWB) of people experiencing the health states. This suggests that MAUIs may not take account of the SWB experienced by patients. This article explores an alternative hypothesis: that a failure of an MAUI to account for variation in SWB is primarily a result of the failure of its descriptive system to include the elements of health that determine SWB and that cannot therefore be included in assessment of the health state utility. METHODS: Survey data are used to determine the extent to which 6 MAUIs with significantly different descriptive systems explain differences between the SWB of the healthy public and patients in 7 disease areas. RESULTS: The EQ-5D-5L takes least account and AQoL-8D most account of SWB. AQoL-8D overpredicts the loss of SWB in 2 cases where hedonic adaptation is known to occur. DISCUSSION: Results suggest that, to a large extent, utility can account for variation in SWB. The case for replacing utility with SWB in economic evaluation studies has arisen, in part, because elements of importance for SWB have been omitted from the descriptive systems of commonly used MAUIs.

Comparing and explaining differences in the magnitude, content, and sensitivity of utilities predicted by the EQ-5D, SF-6D, HUI 3, 15D, QWB, and AQoL-8D multiattribute utility instruments.

BACKGROUND: Cost utility analysis permits the comparison of disparate health services by measuring outcomes in comparable units, namely, quality-adjusted life-years, which equal life-years times the utility of the health state. However, comparability is compromised when different utility instruments predict different utilities for the same health state. The present paper measures the extent of, and reason for, differences between the utilities predicted by the EQ-5D-5L, SF-6D, HUI 3, 15D, QWB, and AQoL-8D. METHODS: Data were obtained from patients in seven disease areas and members of the healthy public in six countries. Differences between public and patient utilities were estimated using each of the instruments. To explain discrepancies between the estimates, the measurement scales and content of the instruments were compared. The sensitivity of instruments to independently measured health dimensions was measured in pairwise comparisons of all combinations of the instruments. RESULTS: The difference between public and patient utilities varied with the choice of instrument by more than 50% for every disease group and in four of the seven groups by more than 100%. Discrepancies were associated with differences in both the instrument content and their measurement scales. Pairwise comparisons of instruments found that variation in the sensitivity to physical and psychosocial dimensions of health closely reflected the items in the instrument's descriptive systems. DISCUSSION: Results indicate that instruments measure related but different constructs. They imply that commonly used instruments systematically discriminate against some classes of services, most notably mental health services. Differences in the instrument scales imply the need for transformations between the instruments to increase the comparability of measurement.

Deriving health utilities from the MacNew Heart Disease Quality of Life Questionnaire.

INTRODUCTION: Quality of life is included in the economic evaluation of health services by measuring the preference for health states, i.e. health state utilities. However, most intervention studies include a disease-specific, not a utility, instrument. Consequently, there has been increasing use of statistical mapping algorithms which permit utilities to be estimated from a disease-specific instrument. The present paper provides such algorithms between the MacNew Heart Disease Quality of Life Questionnaire (MacNew) instrument and six multi-attribute utility (MAU) instruments, the Euroqol (EQ-5D), the Short Form 6D (SF-6D), the Health Utilities Index (HUI) 3, the Quality of Wellbeing (QWB), the 15D (15 Dimension) and the Assessment of Quality of Life (AQoL-8D). METHODS: Heart disease patients and members of the healthy public were recruited from six countries. Non-parametric rank tests were used to compare subgroup utilities and MacNew scores. Mapping algorithms were estimated using three separate statistical techniques. RESULTS: Mapping algorithms achieved a high degree of precision. Based on the mean absolute error and the intra class correlation the preferred mapping is MacNew into SF-6D or 15D. Using the R squared statistic the preferred mapping is MacNew into AQoL-8D. IMPLICATIONS FOR RESEARCH: The algorithms reported in this paper enable MacNew data to be mapped into utilities predicted from any of six instruments. This permits studies which have included the MacNew to be used in cost utility analyses which, in turn, allows the comparison of services with interventions across the health system.

Validity and reliability of the Assessment of Quality of Life (AQoL)-8D multi-attribute utility instrument.

OBJECTIVE: The purpose of this paper was to report tests of the validity and reliability of a new instrument, the Assessment of Quality of Life (AQoL)-8D, which was constructed to improve the evaluation of health services that have an impact upon the psychosocial aspects of the quality of life. METHODS: Australian and US data from a large multi-instrument comparison survey were used to conduct tests of convergent, predictive and content validity using as comparators five other multi-attribute utility (MAU) instruments-the EQ-5D, SF-6D, Health Utilities Index (HUI) 3, 15D and the Quality of Well-Being (QWB)-as well as four non-utility instruments-the SF-36 and three measures of subjective well-being (SWB). A separate three part Australian survey was used to assess test-retest reliability. RESULTS: Results indicate that AQoL-8D correlates more highly with both the SWB instruments and the psychosocial dimensions of the SF-36, and that it is similar to the other MAU instruments in terms of its convergent and predictive validity. The second Australian survey demonstrated high test-retest reliability. CONCLUSIONS: The results indicate that the AQoL-8D is a reliable and valid instrument which offers an alternative to the MAU instruments presently used in economic evaluation studies, and one which is particularly suitable when psychosocial elements of health are of importance.

Needlescopic versus laparoscopic cholecystectomy: a meta-analysis.

BACKGROUND: To systematically analyse clinical trials on needlescopic (NC) versus laparoscopic cholecystectomy (LC) that evaluated the effectiveness of both procedures for the management of cholelithiasis. METHODS: A systematic review of the literature was undertaken. Clinical trials on NC versus LC were selected according to specific criteria and analyzed to generate summative data expressed in standardized mean difference. RESULTS: Sixteen trials on NC versus LC encompassing 1549 patients were retrieved from electronic databases. Only six randomized controlled trials on 317 patients qualified for the meta-analysis according to inclusion criteria. NC was associated with longer operative time and higher conversion rate as compared with LC. There was statistically significant heterogeneity among trials. Intraoperative complications, postoperative complications and total stay in hospital were not significantly different. NC was superior to LC in terms of less post-operative pain and better cosmetic outcomes. CONCLUSION: NC is a safe and effective procedure for the management of gallstone disease. NC is as effective as LC for perioperative complications and total stay in hospital. NC is superior to LC for less post-operative pain and better cosmetic results. NC is associated with longer operative time and higher conversion rate.

Obstetric outcomes among rural Aboriginal Victorians.

Twenty-eight Aboriginal women and 112 age-matched controls were identified from a retrospective chart review of deliveries over a 1-year period in northern Victoria. Significantly more Aboriginal women were screened for gestational diabetes and met criteria for the diagnosis of gestational diabetes. Overall mode of delivery was similar amongst the two groups. Babies born to Aboriginal mothers were significantly smaller and less likely to be breast fed than those from the non-Aboriginal group.

Eye health in rural Australia.

A review of the current literature relating to eye health in rural Australia was conducted. Few studies have been undertaken, with most information provided by the Australian Institute of Health and Welfare databases, The National Trachoma and Eye Health Program of 1980 and the Visual Impairment Project in Victoria in the mid 1990s. Key findings were that the rural population has an increased prevalence of pterygium, cataract, ocular trauma and glaucoma, but no difference in refractive error or diabetic retinopathy (although data are limited). Rural residents are more likely to have seen an optometrist but less likely to have seen an ophthalmologist. Interventions have been undertaken in ophthalmologist training to increase the rural workforce and tele-ophthalmology to provide city-based metropolitan ophthalmological support for rural practitioners. Further epidemiological data and evaluated interventions are urgently required to help identify and address the needs of rural Australian communities.