Surrogate markers of transport distance for out-of-hospital cardiac arrest patients

Michael T. Cudnik, Jing Yao, Dana Zive, Craig Newgard, Alan T. Murray

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Background. Transport of out-of-hospital cardiac arrest (OHCA) patients expeditiously to appropriately equipped hospitals is of paramount importance. Objective. We sought to test the correlation of the centroids of geographic units with the actual transport distance for OHCA patients in order to determine the most appropriate surrogate marker of location for future planning, protocol development, and research projects. Methods. This was a prospective, observational analysis of OHCA events in Portland, Oregon. Using geographic information systems (GISs), the locations of OHCA events and receiving hospitals were identified and geocoded for visual inspection and analysis. Transport distance was calculated via network transport distance and Euclidean distance from multiple surrogate markers of location (centroids of ZIP code, census tract, census block group, and census block). Actual distance from the location of the event was then compared with these surrogate markers to determine the accuracy of alternative markers of OHCA location. Results. Two hundred seventy patients had location data recorded, 163 of whom were transported to a hospital for further care. The median transport distance was 5.17 miles. The transport distance of OHCA patients from the centroid of the census block had the best correlation (R 2 = 0.99) with actual transport distance, whereas the use of the centroid of ZIP codes as a surrogate location had the lowest correlation (R 2 = 0.21). Conclusions. The use of centroids of census blocks via network distance is a valid surrogate for actual location of an OHCA event when calculating transport distance.

Original languageEnglish (US)
Pages (from-to)266-272
Number of pages7
JournalPrehospital Emergency Care
Volume16
Issue number2
DOIs
StatePublished - Apr 2012

Fingerprint

Out-of-Hospital Cardiac Arrest
Biomarkers
Censuses
Geographic Mapping
Geographic Information Systems
Research

Keywords

  • Cardiac arrest
  • Census blocks
  • Emergency medical services
  • Geographic information systems
  • Surrogate markers
  • Transport distance

ASJC Scopus subject areas

  • Emergency Medicine
  • Emergency
  • Medicine(all)

Cite this

Surrogate markers of transport distance for out-of-hospital cardiac arrest patients. / Cudnik, Michael T.; Yao, Jing; Zive, Dana; Newgard, Craig; Murray, Alan T.

In: Prehospital Emergency Care, Vol. 16, No. 2, 04.2012, p. 266-272.

Research output: Contribution to journalArticle

Cudnik, Michael T. ; Yao, Jing ; Zive, Dana ; Newgard, Craig ; Murray, Alan T. / Surrogate markers of transport distance for out-of-hospital cardiac arrest patients. In: Prehospital Emergency Care. 2012 ; Vol. 16, No. 2. pp. 266-272.
@article{6a6832c6e50f4ef0bace8a8c353e719b,
title = "Surrogate markers of transport distance for out-of-hospital cardiac arrest patients",
abstract = "Background. Transport of out-of-hospital cardiac arrest (OHCA) patients expeditiously to appropriately equipped hospitals is of paramount importance. Objective. We sought to test the correlation of the centroids of geographic units with the actual transport distance for OHCA patients in order to determine the most appropriate surrogate marker of location for future planning, protocol development, and research projects. Methods. This was a prospective, observational analysis of OHCA events in Portland, Oregon. Using geographic information systems (GISs), the locations of OHCA events and receiving hospitals were identified and geocoded for visual inspection and analysis. Transport distance was calculated via network transport distance and Euclidean distance from multiple surrogate markers of location (centroids of ZIP code, census tract, census block group, and census block). Actual distance from the location of the event was then compared with these surrogate markers to determine the accuracy of alternative markers of OHCA location. Results. Two hundred seventy patients had location data recorded, 163 of whom were transported to a hospital for further care. The median transport distance was 5.17 miles. The transport distance of OHCA patients from the centroid of the census block had the best correlation (R 2 = 0.99) with actual transport distance, whereas the use of the centroid of ZIP codes as a surrogate location had the lowest correlation (R 2 = 0.21). Conclusions. The use of centroids of census blocks via network distance is a valid surrogate for actual location of an OHCA event when calculating transport distance.",
keywords = "Cardiac arrest, Census blocks, Emergency medical services, Geographic information systems, Surrogate markers, Transport distance",
author = "Cudnik, {Michael T.} and Jing Yao and Dana Zive and Craig Newgard and Murray, {Alan T.}",
year = "2012",
month = "4",
doi = "10.3109/10903127.2011.615009",
language = "English (US)",
volume = "16",
pages = "266--272",
journal = "Prehospital Emergency Care",
issn = "1090-3127",
publisher = "Informa Healthcare",
number = "2",

}

TY - JOUR

T1 - Surrogate markers of transport distance for out-of-hospital cardiac arrest patients

AU - Cudnik, Michael T.

AU - Yao, Jing

AU - Zive, Dana

AU - Newgard, Craig

AU - Murray, Alan T.

PY - 2012/4

Y1 - 2012/4

N2 - Background. Transport of out-of-hospital cardiac arrest (OHCA) patients expeditiously to appropriately equipped hospitals is of paramount importance. Objective. We sought to test the correlation of the centroids of geographic units with the actual transport distance for OHCA patients in order to determine the most appropriate surrogate marker of location for future planning, protocol development, and research projects. Methods. This was a prospective, observational analysis of OHCA events in Portland, Oregon. Using geographic information systems (GISs), the locations of OHCA events and receiving hospitals were identified and geocoded for visual inspection and analysis. Transport distance was calculated via network transport distance and Euclidean distance from multiple surrogate markers of location (centroids of ZIP code, census tract, census block group, and census block). Actual distance from the location of the event was then compared with these surrogate markers to determine the accuracy of alternative markers of OHCA location. Results. Two hundred seventy patients had location data recorded, 163 of whom were transported to a hospital for further care. The median transport distance was 5.17 miles. The transport distance of OHCA patients from the centroid of the census block had the best correlation (R 2 = 0.99) with actual transport distance, whereas the use of the centroid of ZIP codes as a surrogate location had the lowest correlation (R 2 = 0.21). Conclusions. The use of centroids of census blocks via network distance is a valid surrogate for actual location of an OHCA event when calculating transport distance.

AB - Background. Transport of out-of-hospital cardiac arrest (OHCA) patients expeditiously to appropriately equipped hospitals is of paramount importance. Objective. We sought to test the correlation of the centroids of geographic units with the actual transport distance for OHCA patients in order to determine the most appropriate surrogate marker of location for future planning, protocol development, and research projects. Methods. This was a prospective, observational analysis of OHCA events in Portland, Oregon. Using geographic information systems (GISs), the locations of OHCA events and receiving hospitals were identified and geocoded for visual inspection and analysis. Transport distance was calculated via network transport distance and Euclidean distance from multiple surrogate markers of location (centroids of ZIP code, census tract, census block group, and census block). Actual distance from the location of the event was then compared with these surrogate markers to determine the accuracy of alternative markers of OHCA location. Results. Two hundred seventy patients had location data recorded, 163 of whom were transported to a hospital for further care. The median transport distance was 5.17 miles. The transport distance of OHCA patients from the centroid of the census block had the best correlation (R 2 = 0.99) with actual transport distance, whereas the use of the centroid of ZIP codes as a surrogate location had the lowest correlation (R 2 = 0.21). Conclusions. The use of centroids of census blocks via network distance is a valid surrogate for actual location of an OHCA event when calculating transport distance.

KW - Cardiac arrest

KW - Census blocks

KW - Emergency medical services

KW - Geographic information systems

KW - Surrogate markers

KW - Transport distance

UR - http://www.scopus.com/inward/record.url?scp=84857862997&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84857862997&partnerID=8YFLogxK

U2 - 10.3109/10903127.2011.615009

DO - 10.3109/10903127.2011.615009

M3 - Article

C2 - 21950551

AN - SCOPUS:84857862997

VL - 16

SP - 266

EP - 272

JO - Prehospital Emergency Care

JF - Prehospital Emergency Care

SN - 1090-3127

IS - 2

ER -