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Stephen Joel Coons

Publications and source records attributed to Stephen Joel Coons.

At least 19 recordsLinked to original sources
PubMed2006

Self-reported chronic conditions and EQ-5D index scores in the US adult population.

OBJECTIVE: To examine the unique health-related quality of life (HRQoL) decrements associated with common chronic conditions in the general US adult population. METHODS: Data were obtained from a study aimed at establishing a US population-based set of preference weights for the health states defined by the EQ-5D. The EQ-5D is a brief, self-completed instrument for describing and valuing HRQoL. As part of that study, along with the EQ-5D items, data regarding socio-demographic characteristics and chronic medical conditions were collected. The EQ-5D has five dimensions, from which an index score can be calculated that falls on a scale where 0.0 = death and 1.0 = perfect health. Ordinary least squares regression models were conducted using the EQ-5D index score as the dependent variable to estimate the association between each chronic condition and the index score after adjusting for socio-demographic variables. The population sampling weights were applied in the analyses to adjust for the over-sampling of the minority groups. RESULTS: Approximately three-fifths (62.5%) of the study sample reported having at least one of the 18 chronic medical conditions; sinusitis(24.8%), hypertension (23.5%), and arthritis (21.5%) were the most commonly reported conditions. The chronic conditions that had the greatest negative association with EQ-5D index scores were depression and arthritis. CONCLUSION: Unique associations were found between several chronic conditions and HRQoL after accounting for the presence of other conditions and socio-demographic characteristics. The results of this study provide an indication of the relative HRQoL decrements associated with various chronic conditions in the general US adult population. The major limitation of this analysis is the uncertainty of the causal relationship between chronic conditions and HRQoL due to the cross-sectional nature of the study data. In addition, because it was unknown how well the conditions were managed, caution is needed in interpreting study results regarding the relative impact of chronic conditions on HRQoL.

Adult↗
PubMed2006

The VA Ostomy Health-Related Quality of Life Study: objectives, methods, and patient sample.

OBJECTIVE: To present the design and methods of a multisite study of health-related quality of life (HR-QOL) in veterans living with ostomies. RESEARCH DESIGN AND METHODS: Veterans from Tucson, Indianapolis, and Los Angeles VA Medical Centers were surveyed using the validated City of Hope ostomy-specific tool (mCOH-QOL-Ostomy) and the SF-36V. Cases (ostomates) had a major gastrointestinal procedure that required an intestinal stoma, while controls had similar procedures for which an ostomy was not required. Ostomy subjects were recruited for four focus groups in each of two sites divided by ostomy type (colostomy versus ileostomy) and overall mCOH-QOL-Ostomy HR-QOL score (highest versus lowest quartile). The focus groups further evaluated barriers, concerns, and adaptation methods and skills. MAIN OUTCOME MEASURES: This report presents recruitment results, reliability of survey instruments, and demographic characteristics of the sample. RESULTS: The overall response (i.e., recruitment) rate across all sites was 48% and by site was 53%, 57%, and 37%, respectively (p < 0.001). Internal consistency reliability estimates indicated that both instruments remain reliable in this population (Cronbach's alpha for HR-QOL domains/scales: 0.71-0.96). Cases and controls were similar in demographic characteristics. Proportions of minority subjects matched projections from the site patient populations. Subjects with ostomies had significantly longer time since surgery than controls (p < 0.001). Focus groups were comprised of two to six subjects per group and demonstrated racial diversity at the Los Angeles site. CONCLUSIONS: The unique design of our study of VA patients with ostomies is an illustration of a successful mixed methods approach to HR-QOL research. We collected meaningful quantitative and qualitative data that will be used in the development of new approaches to care that will lead to improved functioning and well-being in persons living with ostomies. Subsequent reports will provide the results of this research project.

Aged↗
PubMed2006

A comparative review of health-related quality-of-life measures for use in HIV/AIDS clinical trials.

With the advent of highly active antiretroviral therapy (HAART), HIV-infected patients are living longer and are concerned not only with a treatment's ability to extend their life but also with the quality of the life they are able to lead. Regulatory authorities are also paying closer attention to the use of health-related quality-of-life (HR-QOL) measures in clinical trials and to the subsequent claims that are made based on the results. This paper reviews existing HR-QOL measures reported in the HIV/AIDS literature since 1990 and identifies those most worthy of consideration for use in future clinical trials.A comprehensive review following predefined selection criteria was conducted. Generic and HIV-targeted measures were assessed for content and practicality for the clinical trial setting. The generic measures were additionally reviewed for the ability to produce preference-based index scores and for the existence of normative general population data. Three generic and six HIV-targeted measures met these selection criteria and were then assessed more fully in terms of their development (HIV-targeted measures), psychometric properties and appropriateness for use in clinical trials.It was determined that each of the selected generic measures (i.e. Medical Outcomes Study [MOS] 36-Item Short Form Survey Instrument [SF-36], EQ-5D, Health Utilities Index [HUI]) could serve as a useful adjunct to an HIV-targeted measure in a trial. The Functional Assessment of HIV Infection (FAHI) and MOS-HIV health survey were deemed the two most appropriate HIV-targeted measures. Each of the measures can be self-administered in < or = 10 minutes and there was ample evidence of their excellent psychometric properties. However, they would not be optimal in all HIV-infected subgroups (e.g. treatment naive vs advanced; adolescents vs older adults) targeted for clinical trial interventions. Although there is no one best HR-QOL measure for use in HIV/AIDS clinical trials, based on our review criteria we identified three generic and two HIV-targeted candidate measures. However, these measures have their limitations and it is clear that greater consensus needs to develop regarding more effective and efficient approaches to HR-QOL measurement in HIV/AIDS clinical trials. Along with the increasingly complex HR-QOL measurement task resulting from changes in the HIV-infected population and shifts in the HR-QOL burden associated with HIV infection and its treatment over the past 25 years, it is increasingly important that HR-QOL outcomes become viable endpoints in HIV/AIDS clinical trials.

Acquired Immunodeficiency Syndrome↗
PubMed2005

US valuation of the EQ-5D health states: development and testing of the D1 valuation model.

PURPOSE: The EQ-5D is a brief, multiattribute, preference-based health status measure. This article describes the development of a statistical model for generating US population-based EQ-5D preference weights. METHODS: A multistage probability sample was selected from the US adult civilian noninstitutional population. Respondents valued 13 of 243 EQ-5D health states using the time trade-off (TTO) method. Data for 12 states were used in econometric modeling. The TTO valuations were linearly transformed to lie on the interval [-1, 1]. Methods were investigated to account for interaction effects caused by having problems in multiple EQ-5D dimensions. Several alternative model specifications (eg, pooled least squares, random effects) also were considered. A modified split-sample approach was used to evaluate the predictive accuracy of the models. All statistical analyses took into account the clustering and disproportionate selection probabilities inherent in our sampling design. RESULTS: Our D1 model for the EQ-5D included ordinal terms to capture the effect of departures from perfect health as well as interaction effects. A random effects specification of the D1 model yielded a good fit for the observed TTO data, with an overall R of 0.38, a mean absolute error of 0.025, and 7 prediction errors exceeding 0.05 in absolute magnitude. CONCLUSIONS: The D1 model best predicts the values for observed health states. The resulting preference weight estimates represent a significant enhancement of the EQ-5D's utility for health status assessment and economic analysis in the US.

Adult↗
PubMed2005

Valuations of EQ-5D health states: are the United States and United Kingdom different?

PURPOSE: We sought to compare directly elicited valuations for EQ-5D health states between the US and UK general adult populations. METHODS: We analyzed data from 2 EQ-5D valuation studies where, using similar time trade-off protocols, values for 42 common health states were elicited from representative samples of the US and UK general adult populations. First, US and UK population mean valuations were estimated and compared for each health state. Second, random-effect models were used to compare the US and UK valuations while adjusting for known predictors of EQ-5D valuations (ie, age, sex, health state descriptors) and to investigate whether and how the valuations differ. RESULTS: Population mean valuations of the 42 health states ranged from -0.38 to 0.88 for the United States and from -0.54 to 0.88 for the United Kingdom, with the US mean scores being numerically higher than the UK for 39 health states (mean difference: 0.11; range: -0.01 to 0.25). After adjusting for the main effects of known predictors, the average difference in valuations was 0.10 (P < 0.001). The magnitude of the difference in the US and UK valuations was not constant across EQ-5D health states; greater differences in valuations were present in health states characterized by extreme problems. CONCLUSIONS: Meaningful differences exist in directly elicited TTO valuations of EQ-5D health states between the US and UK general populations. Therefore, EQ-5D index scores generated using valuations from the US general population should be used for studies aiming to reflect health state preferences of the US general public.

Adult↗
PubMed2005

Self-reported health status of the general adult U.S. population as assessed by the EQ-5D and Health Utilities Index.

OBJECTIVE: This study aimed to describe the self-reported health status of the general adult U.S. population using 3 multi-attribute preference-based measures: the EQ-5D, Health Utilities Index Mark 2 (HUI2), and Mark 3 (HUI3). METHODS: We surveyed the general adult U.S. population using a probability sample with oversampling of Hispanics and non-Hispanic blacks. Respondents to this home-visit survey self-completed the EQ-5D and HUI2/3 questionnaires. Overall health index scores of the target population and selected subgroups were estimated and construct validity of these measures was assessed by testing a priori hypotheses. RESULTS: Completed questionnaires were collected from 4048 respondents (response rate: 59.4%). The majority of the respondents were women (52.0%); the mean age of the sample was 45 years, with 14.8% being 65 or older. Index scores (standard errors) for the general adult U.S. population as assessed by the EQ-5D, HUI2, and HUI3 were 0.87 (0.01), 0.86 (0.01), and 0.81 (0.01), respectively. Generally, younger, male and Hispanic or non-Hispanic black adults had higher (better) index scores than older, female and other racial/ethnic adults; index scores were higher with higher educational attainment and household income. The 3 overall preference indices were strongly correlated (Pearson's r: 0.67-0.87), but systematically different, with intraclass correlation coefficients between these indices ranging from 0.59 to 0.77. CONCLUSIONS: This study provides U.S. population norms for self-reported health status on the EQ-5D, HUI2, and HUI3. Although these measures appeared to be valid and demonstrated similarities, health status assessed by these measures is not exactly the same.

Adolescent↗
PubMed2005

An examination of self-reported chronic conditions and health status in the 2001 Medicare Health Outcomes Survey.

OBJECTIVES: To estimate the prevalence of chronic conditions in managed care-enrolled Medicare seniors (age 65 years plus) and to examine the association between self-reported chronic conditions and health status, as measured by the SF-36. METHODS: Data were obtained from the 2001 Medicare Health Outcomes Survey (HOS). The HOS is conducted to assess the quality of care provided to Medicare beneficiaries enrolled in managed care. The survey questionnaire, which was administered by phone or mail, includes the SF-36 and items addressing demographic characteristics, depressive symptoms, and chronic conditions. The SF-36 produces eight multi-item scale scores and physical and mental component summary scores. For this analysis, an ordinary least squares regression model was conducted using the SF-36 scales and summary scores as dependent variables to estimate the association between each chronic condition and the scale scores after adjusting for demographic variables. RESULTS: More than three-fourths of the respondents had at least one chronic condition. Among the conditions, hypertension (56.6%) arthritis of the hip or knee (39.7%) and arthritis of the hand or wrist (33.3%) were the most commonly reported. Compared with other variables, age and arthritis were most highly associated with the SF-36 measures reflective of physical health. Depressive symptoms had the strongest association with the SF-36 measures most reflective of mental health. Among the chronic conditions, the adverse impact of having difficulty in controlling urination, a relatively neglected condition, was only second to depressive symptoms in its negative relationship with vitality, social-functioning, and mental health. CONCLUSION: Chronic conditions were commonly reported among the older adults. The unique associations found between chronic conditions and domains of health status demonstrate the importance of examining the burden of these conditions in terms of functioning and well-being. The findings of this study may help inform decision making at the patient, health plan, and societal levels.

Adult↗
PubMed2003

Commentary on using the SF-36 or MOS-HIV in studies of persons with HIV disease.

The purpose was to compare and comment on use of the SF-36 and MOS-HIV instruments in studies of persons with HIV disease. Three medical information databases were searched to identify examples of HIV studies that included the MOS-HIV or SF-36. Thirty-nine and 14 published articles were identified for illustration in comparing the use of the MOS-HIV and SF-36 in HIV disease, respectively. Support for the reliability and construct validity of the MOS-HIV and SF-36 was found. Ceiling and floor effects were reported for both the MOS-HIV and SF-36; however, ceiling effects were more common for the MOS-HIV, in part due to fewer items in the physical, social, and role functioning domains. The MOS-HIV measures three domains hypothesized to be associated with the health deterioration of HIV disease not measured by the SF-36; however, these domains may not assess aspects of HIV disease that typify the majority of the persons with HIV disease today. National norms for the U.S. adult population (and other nations) are available for the SF-36. In addition, the SF-36 has been used in a wide variety of patient populations, enabling comparisons of HIV-infected persons with persons with other health conditions. No national norms for the MOS-HIV are available. We conclude that there is currently insufficient evidence in the literature to recommend the use of the MOS-HIV over the SF-36 in HIV-infected persons. Although the SF-36 is not targeted at HIV, it may be preferable to use the SF-36 over the MOS-HIV due to fewer ceiling effects, availability of national norms, and the vast amount of data for other populations in the U.S. and around the world. Head-to-head comparisons demonstrating the unique value of the MOS-HIV over the SF-36 are clearly needed. More importantly, additional work needs to be directed at comparing the MOS-HIV and other putatively HIV-targeted instruments to one another to help demarcate aspects of HRQOL that are truly generic versus specific to HIV disease. Using both a generic and targeted HRQOL measure is a good general strategy, but this has not been a typical practice in studies of HIV because the MOS-HIV is so similar in content to the SF-36.

Female↗