Only one third of community pharmacists spotted all dispensing errors hidden in 50 test prescriptions, researchers have revealed at the Royal Pharmaceutical Society annual conference in Birmingham on 8 September 2014.
The findings, from a team at the University of Bath and supported by Pharmacy Research UK, came from a study aiming to investigate the effect of different mental workloads on detecting errors. Pharmacists were required to check 50 real medicines against realistic prescriptions in 25 minutes. Unknown to the participants, the 50 items contained five deliberate dispensing errors (either labelling or product errors). Distractions tested included requiring participants to memorise numbers and a five-minute interruption during checking.
Of the 103 community pharmacists participating in the study, only 36 (35%) detected all five hidden errors. Around half (49 pharmacists) missed one error, while 15 (14%) detected only three out of five, and three pharmacists found only one or two of the errors. No pharmacist missed all five hidden errors. Of the distractions tested, only the five-minute interruption significantly reduced checking accuracy (mean accuracy 70%, compared with 90% with no distraction; P=<0.05).
Although many of the errors missed would not cause patient harm, three out of ten pharmacists missed a labelling error for the controlled drug pethidine, which reduced the dose interval from every four hours to four times a day.
Presenting the research at the conference, author Hannah Family said previous work on mental capacity showed that the rarer an event, the harder it was for humans to identify it during checking tasks, making errors difficult to spot in community pharmacy.
“Published data suggest dispensing errors only occur 3% of the time, which suggests that for visual checking it’s very hard for humans to identify errors.”
Family recommended a variety of steps to reduce dispensing errors, including reducing distractions in the pharmacy, changing pharmacy processes so that safety-critical tasks do not occur when concentration is lowest (e.g. after breaks), and empowering individual pharmacists to control their workload.
The data presented at the conference are contained in a report by Pharmacy Research UK published on 8 September 2014.