Errors and electronic prescribing : a controlled laboratory study to examine task complexity and interruptions effects

Farah MAGRABI, Yau Wai, Simon LI, Richard O DAY, Enrico COIERA

Research output: Journal PublicationsJournal Article (refereed)

42 Citations (Scopus)


Objective: To examine the effect of interruptions and task complexity on error rates when prescribing with computerized provider order entry (CPOE) systems, and to categorize the types of prescribing errors. Design: Two within-subject factors: task complexity (complex vs simple) and interruption (interruption vs no interruption). Thirty-two hospital doctors used a CPOE system in a computer laboratory to complete four prescribing tasks, half of which were interrupted using a counterbalanced design. Measurements: Types of prescribing errors, error rate, resumption lag, and task completion time. Results: Errors in creating and updating electronic medication charts that were measured included failure to enter allergy information; selection of incorrect medication, dose, route, formulation, or frequency of administration from lists and drop-down menus presented by the CPOE system; incorrect entry or omission in entering administration times, start date, and free-text qualifiers; and omissions in prescribing and ceasing medications. When errors occurred, the error rates across the four prescribing tasks ranged from 0.5% (1 incorrect medication selected out of 192 chances for selecting a medication or error opportunities) to 16% (5 failures to enter allergy information out of 32 error opportunities). Any impact of interruptions on prescribing error rates and task completion times was not detected in our experiment. However, complex tasks took significantly longer to complete (F(1, 27)=137.9; p
Original languageEnglish
Pages (from-to)575-583
Number of pages9
JournalJournal of the American Medical Informatics Association
Issue number5
Publication statusPublished - 1 Sep 2010
Externally publishedYes


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