Objective To measure the impact that interruptions have on dispensary accuracy checkers. It is well documented that interruptions impact adversely on task performance.1,–,3 What is less well known is the impact of interruptions in the context of the paediatric dispensary accuracy checking process.

Methods The study instrument was non-participant, direct observation of a discrete, clearly identifiable step within the dispensing process (the accuracy-checking phase of the dispensing process). A prescription requiring two bottles of medicines to be dispensed was created. The medicines were labelled and placed in a tray together with the required paperwork, additional spoons or oral syringes and a dispensing bag. The operatives, both pharmacists and pharmacy technicians, volunteered to participate and were told that they would be timed accuracy checking a prescription and that the object of the observations was to measure the impact of the environment on their work only. That is they themselves were not being assessed. They were also advised that the prescriptions were non-complex, had been clinically screened, and did not contain any errors by design. Each observation (n=34) consisted of two arms as determined by a Latin square. A Latin square ensures that all possible variants are carried out. The observations were undertaken in the dispensary and in an office; the later ensured a quiet environment. In addition a designed interruption was introduced into some of the variants. The interruption consisted of the operative being stopped during the observation and asked to check a dose calculation. Each observation and each interruption was timed and recorded in MS Excel 2007. The variants consisted of accuracy checking the prescription: in the dispensary, in the office, in the dispensary with an interruption and in the office with an interruption.

Results SPSS (IBM) statistical software was used to test for the null hypothesis which showed that there was a significant difference (p<0.05)between the median of the time taken to accuracy check an item in the dispensary with interruption to accuracy checking an item in a sound controlled environment without interruption. When interrupted an operative took longer to accuracy check the prescription. The mean additional time it took when an interruption had occurred in the dispensary when compared with the quiet office without interruption was 33.15 s or 27% longer. One third of operatives took up to 103 s longer to carry out a standard task, one third took up to 40 s longer and one third took up to 25 s longer when compared to non-interrupted observations.

Conclusion It was found that interruptions impacted adversely on dispensary accuracy checkers who were checking a standardised prescription of two items in the dispensary at BCH. Efficiency of the accuracy checking process was shown to reduce by up to 78% or 103 s. Dispensary design should support the reduction of interruptions in critical areas.