208199 Change in access to healthcare as measured by the distance traveled for inpatient medical services in New York State

Monday, November 9, 2009

Ashar Ata, MBBS, MPH , Department of Surgery, Albany Medical College, Albany, NY
Diane McAlpine , Marketing and Planning, Albany Medical College, Albany, NY
Ferdinand J. Venditti, MD, FACP , Department of Medicine, Albany Medical College, Albany, NY

Recent studies have suggested a relative shortage and mal-distribution of physicians across the US during the first decade of the 21st century. We hypothesize that this could adversely affect patients' access to health care services. The purpose of this study is to assess over this same interval the access to medical care as measured by the distance traveled for inpatient hospital services.


We used New York State's SPARCS data from the years 1999 and 2006, containing approximately 2.5 M hospital discharges each year. For each hospitalization, travel distance was estimated by the Euclidean distance between the population-weighted geographic centroid of the patient's zip code and the hospital's exact location. Distances were aggregated for each zip code by Major Diagnosis Category (MDC) and DRG group, and compared between years. DRGs were grouped into Low, Medium, and High intensity groups based on complexity defined by individual DRG weighting.


Excluding NYC, between 1999 and 2006 there was a significant increase in the average distance traveled by patients to seek any service (mean: 2.2 km ą 0.2, 90th percentile: 9.0 km). Some MDCs for which an increased average travel distance was observed were: Respiratory (1.3kmą0.4, 90th percentile: 11.1 km), Circulatory (1.8kmą0.4, 90th percentile: 13.8 km), Digestive (2.3kmą0.5, 90th percentile: 14.5 km), Nervous (3.7 km ą0.7, 90th percentile: 25.6 km), Trauma (6.1 kmą2.2, 90th percentile: 42.7km), and Male Reproductive (14.0km ą1.5, 90th percentile: 54.9 km).

Within each year, average distance traveled was significantly higher for the High intensity DRG group vs. Low and Medium intensity groups (p<0.001). From 1999 to 2006, the increase in average distance traveled also shows a trend of larger increases for higher levels of care; 1.8 km, 2.4 km and 3.5 km respectively for Low, Medium and High intensity DRG groups.


Between 1999 and 2006, patients in NYS (excluding NYC) have, on average, traveled longer distances to receive hospital care. Residents of at least 10% of the zip codes were traveling significantly longer distances for hospitalizations for common services such as those involving the circulatory, respiratory, digestive, and nervous systems. Patients receiving High intensity care traveled farther in both years. From 1999 to 2006, travel distance for High intensity care increased more than for Low intensity care. While temporally these findings coincide with a growing physician shortage, further analysis will be required to determine the exact cause of this change in access to care.

Learning Objectives:
1. Assess the change in access to healthcare services over time in New York State, using GIS . 2. Compare the change in access over time by type (MDC) and complexity (DRG weight) of of service sought.

Keywords: Health Care Access, Geographic Information Systems

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am a Biostatistician and analyzed this data and particpated in composing the abstract and interpreting the results of the data analysis. I am a public health researcher with a Masters in Public Health and have been analyzing health related data for the past 5 years. I have actively contributed and presented research work at national and international public health conferences and journals.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.