Objective To compare the incidence and severity rating of dose prescribing errors before and after the implementation of a commercially available electronic prescribing system at a tertiary care children's hospital.

Methods Dose errors were identified using prescription review to detect errors. Severity rating was determined by five judges using a validated, reliable scoring tool. The mean score for each error was used as an index of severity.

Results Dose prescribing errors occurred in 88 of the 3939 (2.2%) items prescribed for outpatients and inpatients, and on discharge prescriptions prior to the implementation of electronic prescribing (EP). After EP, there were 57 dose errors in 4784 (1.2%) items prescribed (1% absolute reduction (p<0.001 χ² test; 95% CI of difference in proportions −1.6% to −0.5%)). A decrease in the severity rating of dose errors was also seen: dose errors with potentially minor outcomes 35/3939 (0.89%) pre vs 21/4784 (0.44%) post (95% CI of difference in proportions −0.8% to −0.11%, p=0.009 χ² test); moderate outcome 46/3939 (1.17%) pre vs 33/4784 (0.69%) post (95% CI of difference in proportions −0.91% to −0.08, p=0.019, χ² test); severe outcome: 7/3939 (0.18%) pre vs 3/4784 (0.06%) post (95% CI of difference in proportions −0.31% to +0.04, p=0.11, χ² test).

Conclusion Electronic prescribing appears to reduce rates of dosing errors in paediatrics, but larger studies are required to assess the effect on the severity of these errors and in different settings.