Statistical process control for the analysis of quality control in urodynamics: A potential new approach for quality review of urodynamics

Purpose To analyze quality control in urodynamic studies, using a proportion control chart (p-chart) for statistical process control. Materials and Methods This single-center study was conducted at the Urodynamic Center of West China Hospital, Sichuan University. We randomly selected 15 samples from each month in 2020, and 180 urodynamic traces were finally enrolled. We used the p-chart of statistical process control for analysis. We calculated the proportion of the incidence of a selected set of artefacts in the monthly urodynamic study process, including non-standard zero setting, no cough test, incomplete records of all measurements by urodynamicists, catheter displacement, and baseline drift. Through the specific calculation formula of statistical process control, we obtained the values of the center line, lower control limit, and upper control limit. Results All data points of each artefact were within zone A. However, one outlier was found in the p-chart of all artefacts in October, which might have been caused by inexperienced operators. Conclusions Statistical process control may play an important role in the process control of urodynamic studies and guide us in identifying the cause of poor quality in process management.