Objective The aim of this study was to investigate the feasibility of identifying latent errors in paediatric pharmacy and therefore identify potential errors prospectively.

Methods The study environment was the dispensary of Birmingham Children's Hospital, a tertiary referral Children's Hospital. The study instrument was non-participant, direct observation of the final dispensing accuracy checking stage, carried out by pharmacists (n=9) and technicians (n=9) examining a range of factors including workload. These data were supported by semistructured interviews, self completion questionnaires and focus groups within the study population.

Results Analysis of the questionnaires, respondents completed multiple forms, one per session, indicated that a link existed between making errors and awareness of the working environment. Respondents felt stressed one session in three, when they were five times more likely to make an error than on other occasions.

Observations yielded three data sets: (1) the impact that increasing workloads had on the time taken to check items, (2) the number of steps taken to check items and (3) the number of safety (not process) steps performed. Increasing workloads being an indication of potential increases in individual stress levels.

The data showed that for the technician group as work pressure increased the time spent checking an item decreased (mean check time 6.09 min with a SEM of ±1.4 min). For the Pharmacist group the reverse occurred, as workload pressure increased the time taken to check items increased (mean check time 3.27 (SEM±0.4 min)). As workload pressure increased the number of checking steps that individuals took varied. The mean for the technicians was 27.9 (SEM±16.1) and for the pharmacists the mean was 29.6 (SEM±4.72). The third data set, measured safety steps as a function of workload pressure. The mean for the technicians was 45.9 (SEM±17.1) and for the Pharmacists the mean was 63.7 (SEM±10.5).

Key themes that emerged from the interviews included pressure to work faster, noise, quality of training and procedures, workplace design, distracted attention, emotion and paperwork design. All but ‘distracted' and ‘emotion’ factors can be recognised as having basis Risk Factor antecedents.

Conclusions The results were unexpected and showed that as workloads (stress) increased, the time spent on checking an item decreased for the technician group but increased for the pharmacist group. This trend was repeated in the second data set, as workloads (stress) increased the number of steps taken to check an item reduced for the technicians but increased for the pharmacists. Finally, the number of purely safety orientated checks increased for the technicians and showed a decrease for the pharmacists as workloads increased, although the total number of safety checks was higher when compared with the technician group. These results indicate that proactive identification of latent errors will improve safety in the checking process.