Purpose: To evaluate the impact of a prescriber focused individual educational and audit–feedback intervention undertaken by the Nova Scotia Prescription Monitoring Program (NSPMP) in Mar-Apr 2007 to reduce pethidine (meperidine) use.

Method: The NSPMP records all prescriptions for controlled substances dispensed in community pharmacies in Nova Scotia, Canada.  Oral pethidine use from 1 Jul 2005 to 31 Dec 2009 was examined using NSPMP data.  Monthly totals for the following were obtained: number of individual patients who filled at least one pethidine prescription, number of prescriptions and number of tablets dispensed.  Data were analysed graphically to observe overall trends.  The intervention effect was estimated on the logarithmic scale with autocorrelations over time modelled by an integrated autoregressive moving average model for each outcome measure.

Results: An overall trend toward decreasing use from Jul 2005 to Dec 2009 was apparent for all three outcome measures.  The intervention was associated with a statistically significant reduction in pethidine use, after adjusting for the overall long-term trend.  Compared with the pre-intervention period, the monthly number of patients declined by 12% (p less than 0.001; 95% CI, 5% to 18%), prescriptions by 10% (p less than 0.001; 95% CI, 3% to 17%) and tablets by 13.5% (p less than 0.001; 95% CI, 6% to 29%) in the post-intervention period.

Conclusions: Given the risks associated with pethidine, determining that this intervention successfully reduced pethidine use is encouraging.  This study highlights the potential for using population data such as the NSPMP to evaluate the effectiveness of population-level interventions to improve medication use, including professional, organisational, financial and regulatory initiatives.