Evaluation of the efficacy of hand-held computer screens for cardiologists’ interpretations of 12-lead electrocardiograms

doi:10.1016/S0002-8703(99)70194-8

American Heart Journal

Volume 138, Issue 4, October 1999, Pages 765-770

https://doi.org/10.1016/S0002-8703(99)70194-8 Get rights and content

Abstract

Background Newly designed computer-based applications and the development of wireless technology have allowed the transmission of 12-lead electrocardiogram (ECG) waveforms from remote locations to the hand-held computers of cardiologists. If these computer ECGs can be reliably interpreted, then the time to treatment for cardiac patients may be reduced. Methods and Results Twenty classic examples of cardiac abnormalities were chosen to test the efficacy of the hand-held computer’s liquid crystal display (LCD) screen in the interpretation of 12-lead ECGs. Ten cardiologists interpreted these 20 ECGs on the hand-held computers and then twice later on traditional printed paper. The control intraobserver agreement between the sets of paper-displayed ECGs was measured against the agreement between each of the paper sets and the LCD-displayed set of ECGs. Eighty-nine percent (178/200) of the ECGs were interpreted identically by the participants between the 2 paper sets. When comparing the interpretations of the LCD-displayed ECGs with those of each of the paper sets of ECGs, 88.0% (176/200) and 87.5% (175/200) of identical diagnoses were noted. These differences of 1.0% and 1.5% in intraobserver agreement between paper-to-paper and each of the 2 paper-to-LCD comparisons were not significant (P = .75 and P = .88, respectively). Conclusions The strong intraobserver agreement shows that cardiologists make the same diagnoses when viewing LCD-displayed ECGs as they do when viewing paper-displayed ECGs. A study to measure the intraobserver agreement of the decision regarding administration of reperfusion therapy after interpretation of ECGs of patients with acute chest pain is now underway. (Am Heart J 1999;138:765-70.)

Section snippets

Study participants

Ten cardiologists from the Duke University Cooperative Cardiovascular Society with responsibility for interpreting standard 12-lead ECGs were selected from various locations in the United States. Participants were sent (1) the study protocol, (2) a questionnaire to determine their extent of experience with both LCD-displayed ECGs and hand-held computers, and (3) a working draft of directions for use with the Hewlett Packard 200LX Palmtop Computer (Figure 1) with the ECGvu software.

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Results

Table II indicates the intraobserver agreement of paper and LCD displays for each participant. Eighty-nine percent (178/200) of the ECGs were interpreted identically by the participants on the 2 paper-displayed sets. By comparing the interpretations of the LCD-displayed ECGs to those of each paper set of ECGs, 88.0% (176/200) and 87.5% (175/200) of identical diagnoses were noted. These differences of 1.0% and 1.5% in intraobserver agreement between paper-to-paper and each of the 2 paper-to-LCD

Discussion

The 1.0% and 1.5% differences between the intraobserver variability determined in the control group and the intraobserver variability discovered in the 2 experimental comparisons are not statistically significant (P = .75 and P = .88, respectively). This provides evidence that cardiologists make the same diagnoses when looking at LCD-displayed ECGs as they do when viewing traditional paper-displayed ECGs.

The intraobserver agreement for experimental comparisons (88.0% and 87.5%) could possibly

Acknowledgements

We thank the study sponsor, Data Critical Corporation, particularly David Albert, Timothy King, and Aziz El Adrisi; all study participants; cardiologists Kevin Browne, Joseph Calder, Paul Campbell, Myrvin Ellestad, Barry Ramo, Douglas Schocken, Ronald Selvester, Andre Tse, Thomas Wall, and Hadley Wilson; Duke faculty Joseph Greenfield, Eric Eisenstein, Eric Peterson, Robert Sorrentino, and Robert Waugh; cardiology fellow David Whellan; Duke Clinical Research Institute staff Nancy Sinreich; and

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^☆: Supported by Data Critical Corporation. This study is a Duke University Cooperative Cardiovascular Society venture.

^☆☆: The Guest Editor for this manuscript was Robert A. Waugh, MD, Duke University Medical Center, Durham, NC.

^★: Reprint requests: Paul N. Leibrandt, BA, ECG Core Laboratory, Duke Clinical Research Institute, PO Box 17969, Durham, NC 27715.

^★★: 0002-8703/99/$8.00 + 0 4/1/98034

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Evaluation of the efficacy of hand-held computer screens for cardiologists’ interpretations of 12-lead electrocardiograms☆,☆☆,★,★★

Abstract

Section snippets

Study participants

Results

Discussion

Acknowledgements

Ann Emerg Med

J Electrocardiology

Am J Cardiol

Am Heart J

Am J Cardiol

J Am Coll Cardiol

Am J Cardiol

Am J Emerg Med

Ann Emerg Med