Observational Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Jul 8, 2015; 7(13): 1782-1787
Published online Jul 8, 2015. doi: 10.4254/wjh.v7.i13.1782
Impact of geography on organ allocation: Beyond the distance to the transplantation center
Rony Ghaoui, Jane Garb, Fredric Gordon, Elizabeth Pomfret
Rony Ghaoui, Division of Gastroenterology, Baystate Medical Center, Tufts University School of Medicine, Springfield, MA 01199, United States
Jane Garb, Epidemiology/Biostatistics Research Core, Baystate Medical Center, Tufts University School of Medicine, Springfield, MA 01199, United States
Fredric Gordon, Elizabeth Pomfret, Department of Transplantation and Hepatobiliary Diseases, Lahey Medical Center, Tufts University School of Medicine, Burlington, MA 01805, United States
Author contributions: Ghaoui R contributed to conception, data collection and interpretation, manuscript; Garb J contributed to conception, data collection and analysis, manuscript; Gordon F and Pomfret E contributed to data interpretation, manuscript.
Supported by In part Health Resources and Services Administration contract 234-2005-370011C; The content is the responsibility of the authors alone and does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the United States Government.
Ethics approval statement: The study was approved by the institutional review board. Given that the project is based on data from the United Network of Organ Sharing (UNOS) which is already de-identified, it was not deemed a human research project. A copy of the IRB statement is provided as an attachment.
Informed consent statement: The study is based on the UNOS registry, an additional informed consent from the patients does not apply.
Conflict-of-interest statement: All authors have no conflict of interest.
Data sharing statement: The statistical code and dataset are available from the corresponding author at rony.ghaoui@bhs.org. There is no technical appendix. Consent was not obtained but the presented data are anonymized and were obtained from the UNOS hence there is no risk of identification. A copy of the signed statement is provided as an attachment.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Rony Ghaoui, MD, Division of Gastroenterology, Baystate Medical Center, Tufts University School of Medicine, 759 Chestnut St, S2606, Springfield, MA 01199, United States. rony.ghaoui@bhs.org
Telephone: +1-413-7943570 Fax: +1-413-7947364-759
Received: March 19, 2015
Peer-review started: March 21, 2015
First decision: April 27, 2015
Revised: May 9, 2015
Accepted: June 15, 2015
Article in press: June 16, 2015
Published online: July 8, 2015
Processing time: 113 Days and 6.3 Hours
Abstract

AIM: To illustrate the application and utility of Geographic Information System (GIS) in exploring patterns of liver transplantation. Specifically, we aim to describe the geographic distribution of transplant registrations and identify disparities in access to liver transplantation across United Network of Organ Sharing (UNOS) region 1.

METHODS: Based on UNOS data, the number of listed transplant candidates by ZIP code from 2003 to 2012 for Region 1 was obtained. Choropleth (color-coded) maps were used to visualize the geographic distribution of transplant registrations across the region. Spatial interaction analysis was used to analyze the geographic pattern of total transplant registrations by ZIP code. Factors tested included ZIP code log population and log distance from each ZIP code to the nearest transplant center; ZIP code population density; distance from the nearest city over 50000; and dummy variables for state residence and location in the southern portion of the region.

RESULTS: Visualization of transplant registrations revealed geographic disparities in organ allocation across Region 1. The total number of registrations was highest in the southern portion of the region. Spatial interaction analysis, after adjusting for the size of the underlying population, revealed statistically significant clustering of high and low rates in several geographic areas could not be predicted based solely on distance to the transplant center or density of population.

CONCLUSION: GIS represents a new method to evaluate the access to liver transplantation within one region and can be used to identify the presence of disparities and reasons for their existence in order to alleviate them.

Keywords: Health geographic’s; Healthcare disparities; Outcome research

Core tip: Geographic Information System (GIS) studies the impact of geography on many problems through statistical modeling and analysis. It has been used to guide decisions in business, government, environment, but has yet to be adopted in healthcare. Based on the United Network of Organ Sharing database from 2003 to 2012 in one region, GIS revealed clustering of high and low rates of listing for liver transplantation in several geographic areas that could not have otherwise been predicted. This method can be adopted in different parts of the world and contribute to better allocation of resources to decrease the disparities in access to liver transplantation.