Pediatric Informatics: Computer Applications in Child Health (Health ...

378 M. Apkon
pleting a process without them. Accordingly, because of human factors, their use
will be subject to other kinds of errors. For example, ordering a medication from
pick-lists of groups of medications requires caregivers to perceive the differences
among medications. This can result in errors where similarly sounding or similarly
spelled medications could be chosen instead of the correct medication. Scanlon
describes an error of that type where phenobarbital was ordered instead of
phenytoin. 33
Computerized ordering may also require greater reliance on memory when
data is presented on sequential screens whereas handwriting orders may be able to
be completed with the relevant data spread out before the caregiver. Koppel and
colleagues studied failure modes for the use of computerized ordering and identified
two broad categories of error sources: “information errors” which related
to fragmented data access and poor integration across systems; and, “human–
machine interface flaws” that were produced when the electronic workflow did
not correspond to work organization. 34 The errors Koppel describes can also
be examined using the human factors framework in Fig. 29.3. Memory figures
prominently as the design of systems may require the user remember which patient
medications are being ordered for as one moves deeper into the ordering process
when patient selection occurs early. Similarly, users may be relied on to recall
the patient’s medication lists as they order new medications and may not be able
to review the list while ordering because of design limitations. Users may also
erroneously rely on CPOE systems rather than memory for dosing information,
making assumptions that choices displayed in ordering systems reflect acceptable
doses when in fact they may reflect units of distribution from the pharmacy. One
can find examples of errors in using each of the functions described in the human
factors framework (Table 29.1).
This suggests that error-proofing strategies may be useful in the design and
implementation of information systems. The fact that information systems may not
meet their objective in reducing error combined with the potential for introducing
new error modes, argues for the rigorous evaluation and testing of systems prior to
broader implementation.
Table 29.1 Human factor
errors in CPOE
Function used Example of error
Memory Failure to recall which patient was selected
as the user moves through ordering
screens34 Perception Choosing the wrong medication from pick
33, 34 lists
Attention Failure to attend to all components of a task
such as discontinuing orders when medication
orders can not simply be changes35 Judgment Accepting orders that are part of order sets
even when they may be contraindicated35 Motion or action Keyboard entry errors35