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Methodological Challenges in Studies Comparing Prehospital Advanced Life Support with Basic Life Support

Published online by Cambridge University Press:  03 April 2017

Timmy Li ,
Courtney M. C. Jones ,
Manish N. Shah ,
Jeremy T. Cushman  and
Todd A. Jusko
Timmy Li*
Affiliation:
Department of Emergency Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Public Health Sciences, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA
Courtney M. C. Jones
Affiliation:
Department of Emergency Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Public Health Sciences, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA
Manish N. Shah
Affiliation:
Department of Emergency Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Public Health Sciences, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Medicine, Division of Geriatrics/Aging, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA
Jeremy T. Cushman
Affiliation:
Department of Emergency Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Public Health Sciences, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA
Todd A. Jusko
Affiliation:
Department of Public Health Sciences, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA Department of Environmental Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New YorkUSA
*
Correspondence: Timmy Li, BA, EMT-B University of Rochester School of Medicine & Dentistry Department of Emergency Medicine 265 Crittenden Blvd, Box 655C Rochester, New York 14642 USA E-mail: [email protected]
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Abstract

Determining the most appropriate level of care for patients in the prehospital setting during medical emergencies is essential. A large body of literature suggests that, compared with Basic Life Support (BLS) care, Advanced Life Support (ALS) care is not associated with increased patient survival or decreased mortality. The purpose of this special report is to synthesize the literature to identify common study design and analytic challenges in research studies that examine the effect of ALS, compared to BLS, on patient outcomes. The challenges discussed in this report include: (1) choice of outcome measure; (2) logistic regression modeling of common outcomes; (3) baseline differences between study groups (confounding); (4) inappropriate statistical adjustment; and (5) inclusion of patients who are no longer at risk for the outcome. These challenges may affect the results of studies, and thus, conclusions of studies regarding the effect of level of prehospital care on patient outcomes should require cautious interpretation. Specific alternatives for avoiding these challenges are presented.

LiT, JonesCMC, ShahMN, CushmanJT, JuskoTA. Methodological Challenges in Studies Comparing Prehospital Advanced Life Support with Basic Life Support. Prehosp Disaster Med. 2017;32(4):444–450.

Keywords

biasconfoundingepidemiologystudy design
Type
Special Reports
Information
Prehospital and Disaster Medicine , Volume 32 , Issue 4 , August 2017 , pp. 444 - 450
Copyright
© World Association for Disaster and Emergency Medicine 2017 

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Footnotes

Conflicts of interest: none

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