Reliability of self-reported recent antibiotic use among the general population: a cross-sectional study

This study aimed at evaluating the reliability of self-reported recent antibiotic use, including ability to name the antibiotic, among pharmacy customers from the general population.

This cross-sectional observational study of adults took place in pharmacies in northeastern France from January to April 2016. Participants were asked if they had used any antibiotics in the preceding 4 months and if so, to name them. Their reports were compared with an electronic pharmacy dispensing record listing all of the medication dispensed to them in France.

The study included 653 individual customers from 15 pharmacies. Antibiotics had been dispensed 325 times, according to the records, but the patients reported only 237 courses of treatment. Agreement between self-report and the electronic record about whether or not they had used an antibiotic was 80% (κ 0.60). Among the discordant responses, 57% (81/143) involved underreporting. Only 24% (79/325) of the patients could name the antibiotic for each course of treatment; 49% (160/325) could not. The multivariate analysis showed that patients who had purchased an antibiotic in the previous 30 days were 2.5 times more likely to know its name (p 0.01).

Participants' self-reports were relatively reliable for recent use of an antibiotic, but not for its name. Because physicians cannot base prescription decisions on these self-reports only, an electronic pharmacy dispensing file shared among prescribers would be useful.