Quality assurance in diagnostic radiology: practical outcomes

Over the last four years, our Health Physics Department has implemented a quality control programme focusing on the performance of the diagnostic X-ray machines in use at our hospital. The results of the tests performed (X-ray and light field alignment, tube voltage reproducibility and accuracy, ) were used to compare the 1999 and 2002 findings by means of the chi squared and Fischer statistical tests. The comparison has demonstrated that the decrease in the number of non-conformities, also emerging from a simple comparative analysis on the experimental data, was statistically significant with a p<0.05 for all of the X-ray machines examined. This finding confirms that our quality control programme had positive effects on the overall performance of the hospital diagnostic X-ray equipment, and appears to justify the resources employed for its implementation.