Biomedical subjects

Hubert Chen

Publications and source records attributed to Hubert Chen.

5 recordsLinked to original sources

PubMed2006

Measuring disease-specific quality of life in obstructive airway disease: validation of a modified version of the airways questionnaire 20.

BACKGROUND: The Airways Questionnaire 20 (AQ20) is a concise measure of health-related quality of life (HRQL) in obstructive airway disease; however, its original format may underestimate impairment due to the complete cessation of certain activities. METHODS: We revised seven items of the original AQ20 (revised AQ20 [AQ20-R]), adding response options for inability to perform certain activities. We assessed the performance of the AQ20-R among 352 adults with various airway conditions identified through a random telephone sample. Concurrent validity of the AQ20-R was assessed relative to the Short Form-12 (SF-12) physical component summary (PCS), FEV(1), and medication use. Predictive validity was assessed relative to health-care utilization among 278 subjects studied longitudinally. RESULTS: Twenty-one of 352 subjects were unable to perform at least one activity. These subjects demonstrated higher AQ20-R scores (p < 0.001) indicating worse HRQL. Mean (+/- SD) AQ20-R scores differed significantly (p < 0.001) among subjects with COPD (8.9 +/- 5.2), asthma (6.7 +/- 5.0), and chronic bronchitis (4.7 +/- 4.2). At baseline, the AQ20-R correlated with the SF-12 PCS (r = - 0.55, p < 0.001) and FEV(1) (r = - 0.43, p < 0.001), and was associated with the use of respiratory-specific therapies (p </= 0.001). In multivariate models, the AQ20-R was an independent predictor of outpatient visits (odds ratio, 2.2; 95% confidence interval, 1.6 to 3.1), emergency department visits (odds ratio, 2.9; 95% confidence interval, 1.9 to 4.6), hospitalization (odds ratio, 2.8; 95% confidence interval, 1.6 to 4.9), and ICU admission (odds ratio, 3.0; 95% confidence interval, 1.2 to 7.3) during the following year. CONCLUSIONS: The AQ20-R is a valid respiratory-specific HRQL measure that accounts for activity cessation among the most impaired and can be used across various airway conditions.

Aged↗

PubMed2005

Evaluating change in health-related quality of life in adult rhinitis: responsiveness of the Rhinosinusitis Disability Index.

BACKGROUND: The Rhinosinusitis Disability Index (RSDI) is a validated measure of health-related quality of life (HRQL) in rhinitis. Responsiveness of the RSDI to changes in health status over time has not been described. METHODS: We studied adults with a self-reported physician diagnosis of rhinitis identified through a national telephone survey. HRQL was assessed at baseline and at 24 months using the RSDI. Symptom severity, physical health status (SF-12 PCS), psychological mood (CES-D), and perceived control of symptoms were also assessed at the time of each interview. In addition, we ascertained specific health outcomes attributed to rhinitis, including days of restricted activity, job effectiveness, number of physician visits, and medication costs. RESULTS: Of 109 subjects interviewed at baseline, 69 (63%) were re-interviewed 24 months later. RSDI scores improved by = 0.5 standardized response mean in 13 (19%) subjects and worsened in 17 (25%). Change in the RSDI over time correlated with changes in symptom severity (r = 0.38, p = 0.001), physical health (r = -0.39, p = 0.001), mood (r = 0.37, p = 0.002) and perceived control of symptoms (r = -0.37, p = 0.01). In multivariate analyses adjusted for baseline health status, improvement in RSDI was associated with less restricted activity (p = 0.01), increased job effectiveness (p = 0.03), and decreased medication costs (p = 0.05), but was not associated with change in the number of physician visits from baseline (p = 0.45). CONCLUSION: The RSDI is responsive to changes in health status and predicts rhinitis-specific health outcomes.

Adolescent↗

PubMed2004

Health-related quality of life in adult rhinitis: the role of perceived control of disease.

BACKGROUND: Factors affecting health-related quality of life (HRQOL) in adult rhinitis have not been well described. OBJECTIVE: To understand how symptom severity, physical functioning, psychological distress, and perceived control of disease relate to HRQOL in a population-based sample of adults with rhinitis. METHODS: We conducted telephone interviews in 109 adults with rhinitis recruited via random digit dialing. We assessed HRQOL by using the Rhinosinusitis Disability Index, physical functioning by using the physical component score of the Short Form-12, and psychological distress by using the Center for Epidemiologic Studies Depression Scale. To evaluate the role of patient-perceived control of disease in rhinitis, we developed a new 8-item instrument, the Perceived Control of Rhinitis Questionnaire. RESULTS: Lower HRQOL correlated with greater symptom severity ( r=0.57), poorer physical functioning ( r=-0.41), greater psychological distress ( r=0.44), and less perceived control ( r=-0.53). In a multivariate model, symptom severity ( P < .001), psychological distress ( P <.001), and perceived control ( P <.001) were all independent predictors of HRQOL. Adding functional and psychosocial measures to a base model with demographics and disease severity explained an additional 26% of variance in HRQOL. CONCLUSIONS: Although disease severity is an important factor in HRQOL, psychosocial factors, such as perceived control of disease, explain a substantial amount of the variability in HRQOL among adults with rhinitis.

Adolescent↗

PubMed2003

W/SiC x-ray multilayers optimized for use above 100 keV.

We have developed a new depth-graded multilayer system comprising W and SiC layers, suitable for use as hard x-ray reflective coatings operating in the energy range 100-200 keV. Grazing-incidence x-ray reflectance at E = 8 keV was used to characterize the interface widths, as well as the temporal and thermal stability in both periodic and depth-graded W/SiC structures, whereas synchrotron radiation was used to measure the hard x-ray reflectance of a depth-graded multilayer designed specifically for use in the range E approximately 150-170 keV. We have modeled the hard x-ray reflectance using newly derived optical constants, which we determined from reflectance versus incidence angle measurements also made using synchrotron radiation, in the range E = 120-180 keV. We describe our experimental investigation in detail compare the new W/SiC multilayers with both W/Si and W/B4C films that have been studied previously, and discuss the significance of these results with regard to the eventual development of a hard x-ray nuclear line telescope.

Journal Article↗

PubMed2002

Moral hypocrisy: addressing some alternatives.

Two studies addressed alternative explanations for 3 pieces of evidence supporting the existence of moral hypocrisy. In Study 1, no support was found for the idea that low salience of social standards accounts for falsifying the result of a coin flip to assign oneself a more desirable task. In Study 2, no support was found for the idea that responses of those who honestly win the flip account for the higher ratings of morality of their action by participants who assign themselves the more desirable task after flipping the coin. Also, no support was found for the idea that responses of those who honestly win the flip account for the inability of personal moral responsibility measures to predict moral action. Instead, results of both studies provided additional evidence of moral hypocrisy.

Decision Making↗