Abstract
Objective Clinicians using clinical decision support (CDS) to prescribe medications have an
obligation to ensure that prescriptions are safe. One option is to verify the safety
of prescriptions if there is uncertainty, for example, by using drug references. Supervisory
control experiments in aviation and process control have associated errors, with reduced
verification arising from overreliance on decision support. However, it is unknown
whether this relationship extends to clinical decision-making. Therefore, we examine
whether there is a relationship between verification behaviors and prescribing errors,
with and without CDS medication alerts, and whether task complexity mediates this.
Methods A total of 120 students in the final 2 years of a medical degree prescribed medicines
for patient scenarios using a simulated electronic prescribing system. CDS (correct,
incorrect, and no CDS) and task complexity (low and high) were varied. Outcomes were
omission (missed prescribing errors) and commission errors (accepted false-positive
alerts). Verification measures were access of drug references and view time percentage
of task time.
Results Failure to access references for medicines with prescribing errors increased omission
errors with no CDS (high-complexity: χ
2(1) = 12.716; p < 0.001) and incorrect CDS (Fisher's exact; low-complexity: p = 0.002; high-complexity: p = 0.001). Failure to access references for false-positive alerts increased commission
errors (low-complexity: χ
2(1) = 16.673, p < 0.001; high-complexity: χ
2(1) = 18.690, p < 0.001). Fewer participants accessed relevant references with incorrect CDS compared
with no CDS (McNemar; low-complexity: p < 0.001; high-complexity: p < 0.001). Lower view time percentages increased omission (F(3, 361.914) = 4.498; p = 0.035) and commission errors (F(1, 346.223) = 2.712; p = 0.045). View time percentages were lower in CDS-assisted conditions compared with
unassisted conditions (F(2, 335.743) = 10.443; p < 0.001).
Discussion The presence of CDS reduced verification of prescription safety. When CDS was incorrect,
reduced verification was associated with increased prescribing errors.
Conclusion CDS can be incorrect, and verification provides one mechanism to detect errors. System
designers need to facilitate verification without increasing workload or eliminating
the benefits of correct CDS.
Keywords
automation bias - clinical decision support systems - medication alerts - cognitive
load - medication errors - human–computer interaction
