Temporal decline in the improved detection rates following OASIS workshops

Introduction and hypothesis: To evaluate the long-term sustainability of the effect of a hands-on workshop on the diagnosis of deliveries complicated by obstetrical anal sphincter injuries (OASIS). Methods: A population-based retrospective cohort study looking over a 4-year period, 1 year before and 3 years after an OASIS workshop. All deliveries that took place at the Soroka University Medical Center during the study period were included. Data were collected from the obstetrical electronic database. Interrupted time series analysis assessing the change in the OASIS detection rate over time from the workshop was conducted, assuming that the OASIS rate remained constant during the study period. Results: During the study period, 147 parturients suffered from OASIS. The baseline characteristics of the patients before and after the workshop did not differ. In the year following the workshop a significant increase in the detection rate was noted compared with the year prior to the workshop. In an interrupted time series analysis, the improved detection rate declined with time. In the last year following the workshop the detection rate declined, almost reaching the pre-workshop rate. Conclusions: Attending an OASIS workshop increases the detection rate in the year following the workshop but declines gradually. To maximize its benefits, the workshop must be repeated periodically.