eDrugCalc: an online self‐assessment package to enhance medical students' drug dose calculation skills

Abstract

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• Dose calculation errors are an important cause of some of the most serious medication incidents in advanced healthcare systems. • A number of small studies have shown that dose calculations are poorly performed by hospital doctors, nurses and medical students. WHAT THIS PAPER ADDS• The performance of dose calculations was highly variable amongst a large cohort of medical students from a leading UK medical school.• Calculations that involved converting concentrations expressed as percentage or calculating infusion rates were identified as major weaknesses.• The availability of an online self-assessment and education package, coupled with encouragement and twice-yearly formative assessment, led to a significant improvement in performance. AIMSDose calculation errors can cause serious life-threatening clinical incidents. We designed eDrugCalc as an online self-assessment tool to develop and evaluate calculation skills among medical students. METHODSWe undertook a prospective uncontrolled study involving 1727 medical students in years 1-5 at the University of Edinburgh. Students had continuous access to eDrugCalc and were encouraged to practise. Voluntary self-assessment was undertaken by answering the 20 questions on six occasions over 30 months. Questions remained fixed but numerical variables changed so each visit required a fresh calculation. Feedback was provided following each answer. RESULTSFinal-year students had a significantly higher mean score in test 6 compared with test 1 [16.6, 95% confidence interval (CI) 16.2, 17.0 vs. 12.6, 95% CI 11.9, 13.4; n = 173, P < 0.0001 Wilcoxon matched pairs test] and made a median of three vs. seven errors. Performance was highly variable in all tests with 2.7% of final-year students scoring < 10/20 in test 6. Graduating students in 2009 (30 months' exposure) achieved significantly better scores than those in 2007 (only 6 months): mean 16.5, 95% CI 16.0, 17.0, n = 184 vs. 15.1, 95% CI 14.5, 15.6, n = 187; P < 0.0001, Mann-Whitney test. Calculations based on percentage concentrations and infusion rates were poorly performed. Feedback showed that eDrugCalc increased confidence in calculating doses and was highly rated as a learning tool. CONCLUSIONSMedical student performance of dose calculations improved significantly after repeated exposure to an online formative dose-calculation package and encouragement to develop their numeracy. Further research is required to establish whether eDrugCalc reduces calculation errors made in clinical practice.

Impact of a Required Pharmaceutical Calculations Course on Mathematics Ability and Knowledge Retention

“…9,12,21 McQueen and colleagues reported that medical students had the most difficulty performing percentage and infusion rate calculations, and Bayne and Bindler reported that practicing nurses had the most difficulty performing calculations that required multiple steps or required a conversion factor that was not provided. 21,22 Students in this study improved in all of the above content areas following the required pharmaceutical calculations course, with the exception of percentages. Based on these findings, more emphasis should be placed on percentage calculations in our pharmaceutical calculations course.…”

“…21 Also, students' math ability at the time of matriculation varied greatly. Following the required pharmaceutical calculations course, student mathematics abilities were more aligned as evidenced by the smaller standard deviations on the posttest among both cohorts of students.…”

Predictors of numeracy performance in undergraduate psychology, nursing and medical students

“…Also, one of the characteristics of numeracy is that it is context dependent (e.g. FitzSimons, 2002), and so what exactly constitutes numeracy differs between groups with psychologists viewing numeracy as statistics competency (Mulhern & Wylie, 2004), and nurses and medics viewing it as the ability to work with numbers in their occupational setting (Hutton, Coben, Hall et al, 2010;McQueen, Begg & Maxwell, 2009). As a result of these differences, it was expected that different patterns of results would be observed for each of the three groups.…”

An agenda for UK clinical pharmacology: How should teaching of undergraduates in clinical pharmacology and therapeutics be delivered and assessed?

“…Online resources can provide attractive active learning experiences that are constantly accessible. These may aid understanding of key principles, support a student formulary [23], offer skills practice [24] and provide case‐based therapeutic problems [25]. As the change from paper to electronic prescribing spreads worldwide, aided by advances in virtual reality environments, this approach will be able to provide increasingly realistic simulation of real‐world prescribing.…”