Factors influencing doctors’ ability to calculate drug doses correctly

Abstract

Doctors and medical students are more likely to make errors in drug dose calculations when the strengths of drug solutions are expressed as ratios or percentages. We have already described how a doctor's specialty influences their drug dose calculation skills, having surveyed almost 3000 doctors in an online survey. Better teaching of drug administration skills or reinforcement of existing skills would appear to be needed. We sought to identify doctors that might benefit particularly from such teaching by other means than specialty alone, by subjecting existing data to further analysis. Almost 3000 doctors subscribing to a UK-based internet content provider had participated in an online questionnaire concerning drug-dose calculation. Each doctor's score in the multiple choice questionnaire was cross referenced with demographic data obtained from the hosts of the original survey whilst maintaining anonymity. Newly and recently qualified doctors, and doctors working in the community, struggled most with the calculations (p < 0.0001). There were also highly significant differences in the performances of doctors from different medical schools (p < 0.0001). As a new training programme for junior doctors is being introduced in the UK; we recommend that drug administration skills are given a prominent place in the curriculum, and again call for the standardisation of ampoule labelling to mass concentration.

Medication knowledge, certainty, and risk of errors in health care: a cross-sectional study

“…It was reassuring that working in hospitals and postgraduate specialization was associated with high knowledge, since the most advanced medical treatments take place in hospitals, and potentially harmful medication procedures are handled by specially trained nurses, both in hospitals and in primary health care establishments. Working place has also been indicated as a factor influencing doctors' ability in drug dose calculations [25]. …”

Retention of drug administration skills after intensive teaching

“…The results would also appear to be clinically significant, in that those students who received the most intensive teaching were more likely to pass the drug administration OSPE station, implying that they had achieved the level of competence expected of a junior doctor. However, a substantial minority did not meet this standard, and neither do many, more senior, doctors [2][3][4][5][6][7]15]. Therefore, better education cannot be the only solution; the problem of labelling drug solutions as ratios and percentages must also be addressed.…”

The need to address poor numeracy skills in the emergency department environment

“…We believe that despite the small body of evidence, there is sufficient indisputable proof that many doctors would also benefit from further education incorporating similar interventions. Other researchers have made the call for increased education in the calculation of drug doses . However, as mathematical competency extends far beyond the calculation of drug doses, we suggest that a wider perspective must be taken.…”

“…[3][4][5] Although most published research has involved nurses and nursing students, the ability of paramedics, pharmacists, medical students and doctors to perform simple drug calculations has also been demonstrated. [5][6][7][8] For example, a study undertaken in Australia and New Zealand demonstrated that among a group of doctors the percentage answering questions on drug dose calculations accurately ranged from 46% for medical students, 63% for house surgeons and 72% for registrars. 6 Out of 61 participants, only eight participants answered all five questions correctly.…”