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Alexander C Tsai

Publications and source records attributed to Alexander C Tsai.

10 recordsLinked to original sources
PubMed2006

Overcoming bias in estimating the volume-outcome relationship.

OBJECTIVE: To examine the effect of hospital volume on 30-day mortality for patients with congestive heart failure (CHF) using administrative and clinical data in conventional regression and instrumental variables (IV) estimation models. DATA SOURCES: The primary data consisted of longitudinal information on comorbid conditions, vital signs, clinical status, and laboratory test results for 21,555 Medicare-insured patients aged 65 years and older hospitalized for CHF in northeast Ohio in 1991-1997. STUDY DESIGN: The patient was the primary unit of analysis. We fit a linear probability model to the data to assess the effects of hospital volume on patient mortality within 30 days of admission. Both administrative and clinical data elements were included for risk adjustment. Linear distances between patients and hospitals were used to construct the instrument, which was then used to assess the endogeneity of hospital volume. PRINCIPAL FINDINGS: When only administrative data elements were included in the risk adjustment model, the estimated volume-outcome effect was statistically significant (p=.029) but small in magnitude. The estimate was markedly attenuated in magnitude and statistical significance when clinical data were added to the model as risk adjusters (p=.39). IV estimation shifted the estimate in a direction consistent with selective referral, but we were unable to reject the consistency of the linear probability estimates. CONCLUSIONS: Use of only administrative data for volume-outcomes research may generate spurious findings. The IV analysis further suggests that conventional estimates of the volume-outcome relationship may be contaminated by selective referral effects. Taken together, our results suggest that efforts to concentrate hospital-based CHF care in high-volume hospitals may not reduce mortality among elderly patients.

Aged↗
PubMed2005

Physician decisions to discontinue long-term medications using a two-stage framework: the case of growth hormone therapy.

BACKGROUND: Physician decisions to discontinue prescription medications for chronic conditions are fundamental determinants of drug use but have been inadequately studied. The decision to stop growth hormone (GH) therapy is an important example because of high cost (approximately $26,000/y for a 48-kg child), complexity of treatment options, and expansion of patient populations. AIM: The aim of this study was to identify the factors that influence physician recommendations in the process of discontinuing therapy. DESIGN: A random sample of half of U.S. pediatric endocrinologists (n = 265) was mailed a survey that included case scenarios of GH-deficient adolescents. Decision options involved a 2-stage framework to 1) initiate change in ongoing GH therapy (by discussing discontinuing GH with the family but not yet stopping treatment), and 2) take action to discontinue ongoing GH therapy (by terminating GH or reducing the dose to adult maintenance level). MAIN OUTCOME MEASURE: Physician recommendations. RESULTS: The response rate was 83.8%. Physiological indices of growth potential (growth velocity, bone age) significantly influenced discontinuation decisions (both P < 0.001). However, family preference, child's height, and physician attitudes exerted independent effects (each P < 0.05). Treatment price had little influence. Together, these variables accounted for 60% to 70% of the variation in recommendations. Their relative influence differed by stage in the discontinuation process. CONCLUSION: The variables in our framework substantially explain discontinuation decisions. The data demonstrate the importance of both physiological and nonphysiological factors. The results suggest that physicians value even small gains as final height approaches, although an additional 20% expenditure may be needed to gain the last 1% to 3% of adult height.

Adolescent↗
PubMed2005

A meta-analysis of interventions to improve care for chronic illnesses.

OBJECTIVE: To use empirical data from previously published literature to address 2 research questions: (1) Do interventions that incorporate at least 1 element of the Chronic Care Model (CCM) result in improved outcomes for specific chronic illnesses? (2) Are any elements essential for improved outcomes? STUDY DESIGN: Meta-analysis. METHODS: Articles were identified from narrative literature reviews and quantitative meta-analyses, each of which covered multiple bibliographic databases from inception to March 2003. We supplemented this strategy by searching the MEDLINE database (1998-2003) and by consulting experts. We included randomized and nonrandomized controlled trials of interventions that contained 1 or more elements of the CCM for asthma, congestive heart failure (CHF), depression, and diabetes. We extracted data on clinical outcomes, quality of life, and processes of care. We then used random-effects modeling to compute pooled standardized effect sizes and risk ratios. RESULTS: Of 1345 abstracts screened, 112 studies contributed data to the meta-analysis: asthma, 27 studies; CHF, 21 studies; depression, 33 studies; and diabetes, 31 studies. Interventions with at least 1 CCM element had consistently beneficial effects on clinical outcomes and processes of care across all conditions studied. The effects on quality of life were mixed, with only the CHF and depression studies showing benefit. Publication bias was noted for the CHF studies and a subset of the asthma studies. CONCLUSIONS: Interventions that contain at least 1 CCM element improve clinical outcomes and processes of care--and to a lesser extent, quality of life--for patients with chronic illnesses.

Chronic Disease↗
PubMed2003

Declining payments for emergency department care, 1996-1998.

STUDY OBJECTIVE: We describe recent trends in payments from different payer classes and assess their relative importance to the financial solvency of emergency departments. METHODS: We used Medical Expenditure Panel Survey data from 1996 and 1998. The unit of analysis was the ED visit. Primary outcome measures were ED charges and payments. The independent variable of interest was payer class, and therefore, we limited our analysis to those either uninsured or covered by Medicare, Medicaid, or private insurance. RESULTS: From 1996 to 1998, a declining percentage of total charges were paid, from 60.3% to 53.0% (difference -7.3%; 95% confidence interval [CI] -11.3% to -3.5%). Although the percentage of total charges paid by Medicaid, Medicare, and the uninsured remained constant, the percentage of total charges paid by the privately insured declined from 75.1% to 63.4% (difference -11.7%; 95% CI -16.6% to -6.7%). Overall, adjusted mean ED charge increased from 695 dollars to 798 dollars (difference 103 dollars; 95% CI 61 dollars to 146 dollars). Two payer classes experienced statistically significant increases in adjusted mean charge: the uninsured, from 544 dollars to 740 dollars (difference 196 dollars; 95% CI 62 dollars to 330 dollars), and the privately insured, from 658 dollars to 813 dollars (difference 151 dollars; 95% CI 103 dollars to 199 dollars). Although the adjusted mean payment rate for the uninsured remained stable, the adjusted mean payment rate for the privately insured declined from 77.7% to 65.7% (difference -12.0%; 95% CI -13.4% to -10.7%). CONCLUSION: The ability of EDs to provide emergency care to all regardless of ability to pay is increasingly threatened by declining overall payment rates. Cost shifting to fund care for the uninsured is an increasingly untenable financing strategy.

Emergency Service, Hospital↗
PubMed2003

Conflicts between commercial and scientific interests in pharmaceutical advertising for medical journals.

In 1992, researchers from the University of California, Los Angeles, published a study on the scientific merit and validity of pharmaceutical advertisements in medical journals. Their results led them to conclude, provocatively, that many pharmaceutical advertisements contained deficiencies in areas in which the U.S. Food and Drug Administration had established explicit standards of quality. This article provides a detailed account of third-party reactions to the study following its publication in the Annals of Internal Medicine, as well as the implications for those involved, including the authors, editors, and publisher. The increasingly diverging interests between medical journal editors and publishers are also discussed and highlighted by two recent cases of editors' departures from prominent general-interest medical journals.

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