Improving the accuracy of medication history taking in a diabetic eye clinic

To assess whether the use of a pre-visit medication questionnaire combined with clinical interview improves the accuracy of medication history taking when compared with direct questioning only, for new patients attending a diabetic eye clinic.

A service evaluation was undertaken using a retrospective case-control design. Fifty consecutive new patients visiting the clinic before a new pre-visit medication questionnaire was introduced were used as controls (group 1). New patients attending the clinic after the introduction of the questionnaire, who had been sent the questionnaire and completed it (group 2), were then matched to patients in group 1 over a 6-month period. The reported medication histories for both groups were then checked with the patients' GP.

Forty-two matched pairs were identified. There was no significant difference (P=0.71) between the number of medications prescribed in group 1 (mean=6.2; standard deviation [SD]=3.8) and group 2 (mean=6.5; SD=2.9). However, there was a highly significant difference in the number of errors in the stated medication lists between groups 1 and 2: this favoured group 2, who completed a pre-clinic questionnaire before attending the clinic.

The use of a pre-clinic questionnaire combined with clinical interview provides a significantly more accurate assessment of a patient's current medication list than interview alone.