Biomedical subjects

Gabriel Picone

Publications and source records attributed to Gabriel Picone.

4 recordsLinked to original sources

PubMed2005

Longitudinal analysis of the relationship between regular eye examinations and changes in visual and functional status.

OBJECTIVES: To determine whether regular eye examinations are associated with a greater or lesser rate of loss of ability to read newsprint, onset of blindness or low vision, or onset of limitations in instrumental activities of daily living (IADLs) and activities of daily living (ADLs). DESIGN: A sample of 14,215 Medicare beneficiaries observed between 1994 and 1999 linked to the 1994 and 1999 National Long-Term Care Surveys (NLTCS). Effects of annual examinations were assessed using instrumental variables. SETTING: The Medicare-linked NLTCS is representative of U.S. elderly persons from 1994 to 1999. PARTICIPANTS: Longitudinal observational study of persons aged 65 and older. MEASUREMENTS: Change in self-reported and provider-reported vision and change in functional limitations associated with vision related to the number of years with eye examinations and other factors. RESULTS: Persons with more-regular eye examinations between 1994 and 1998 were less likely to have experienced a decline in vision or in functional status between 1994 and 1999. On average, an additional year with an eye examination was associated with a decrease in the probability of becoming unable to read newsprint of 0.12 (P=.03), a lower probability of onset of low vision or blindness of 0.009 (P=.06), and a decrease in the probability that the number of functional limitations increased of 0.13 (P=.002) for IADLs and 0.05 (P=.003) for ADLs. CONCLUSION: Elderly persons who have regular eye examinations experience less decline in vision and functional status.

Activities of Daily Living↗

PubMed2004

Do routine eye exams improve vision?

We use a longitudinal national sample of Medicare claims linked to the National Long-Term Care Survey (NLTCS) to assess the productivity of routine eye examinations. Although such exams are widely recommended by professional organizations for certain populations, there is limited empirical evidence on the productivity of such care. We measure two outcomes, the ability to continue reading, and no onset of blindness or low vision, accounting for potential endogeneity of frequency of eye exams. Using instrumental variables, we find a statistically significant and beneficial effect of routine eye exams for both outcomes. Marginal effects for reading ability are large, but decline in the number of years with eye exams. Effects for blindness/low vision are smaller for the general elderly population, but larger for persons with diabetes. Instrumental variables provide a useful approach for assessing the productivity of particular interventions, particularly in situations in which randomized controlled trials are expensive or perhaps unethical and difficult to conduct over a lengthy time period.

Cost-Benefit Analysis↗

PubMed2003

Analysis of hospital length of stay and discharge destination using hazard functions with unmeasured heterogeneity.

The hospital length-of-stay and the discharge destination of a Medicare patient are the outcomes of one decision process involving the interests of the patient, the hospital, and the firms offering covered post-hospital care. We use a competing risk hazard estimation procedure and adjust for unobserved heterogeneity with a non-parametric technique to identify significant factors in the decision process. A patient's health and socio-economic characteristics, the availability of informal care, local market area conditions, and Medicare policies influence length-of-stay and discharge destination. The substitution we find between hospital and post-hospital care and among post-hospital care alternatives has policy implications for Medicare.

Health Services Research↗

PubMed2002

Are for-profit hospital conversions harmful to patients and to Medicare?

We examine how changes in hospital ownership to and from for-profit status affect quality and Medicare payments per hospital stay. We hypothesize that hospitals converting to for-profit ownership boost post acquisition profitability by reducing dimensions of quality not readily observed by patients and by raising prices. We find that 1-2 years after conversion to for-profit status, mortality of patients, which is difficult for outsiders to monitor, increases while hospital profitability rises markedly and staffing decreases. Thereafter, the decline in quality is much lower. A similar decline in quality is not observed after hospitals switch from for-profit to government or private nonprofit status.

Diagnosis-Related Groups↗