An audit of film reject and repeat rates in a department of dental radiology.

A study of film reject and repeat rates was undertaken in the Department of Dental Radiology of King's College School of Medicine and Dentistry over a 6 month period. The aim of the study was to assess the effects of changes implemented after a previous audit, and to carry out a more detailed analysis of the factors influencing the reject and repeat rates using a larger volume of data. The information recorded included the equipment and projection used, and the age of the patient if under 16 years. The overall reject rate was 3.06%, 1.84% less than recorded in the earlier study, and the repeat rate was 0.93%. Positioning errors were the most frequent cause for rejection. Significant differences in reject rates were noted between different projections, and also between qualified staff and those in training. The rejection rate for patients under 16 years was not significantly higher than for patients over 16 years, the most frequent cause of rejection was still positioning faults, but patient movement accounted for a larger proportion of the rejects than was the case in adult patients. The results demonstrate the role of audit in isolating factors leading to additional exposures. The effectiveness of changes implemented following a reject film analysis is also shown.