Estimation of adverse drug reaction reporting in Iran: Correction for underreporting.

PROPOSE

Underreporting of Adverse Drug Reactions (ADRs) reduces the sensitivity of pharmacovigilance systems. We described ADR reporting and its trend from 1999 to 2017 and estimated the ADR underreporting in the Iranian Pharmacovigilance Center.

METHODS

We expressed the number of ADR reporting per inhabitants and admissions and their possible trends. Finally, ADR underreporting percentages were estimated by three approaches: prospective studies, literature review, stratification of the country; and the trend of the proportion of ADR per inhabitants was corrected.

RESULTS

The proportion of ADR reporting was 15.3 per 100 000 inhabitants (95% CI: 15.2, 15.8) and 10.0 per 100 000 admissions (95% CI: 9.8, 10.2) in 2017, and its trend was increasing with 16.3% average change per annum during 19 years. The median of estimated percentages of underreporting was 76.0% (IQR: 64.32-81.35). After the correction, the mean proportion of ADR reporting for 19 years reached from 5.87 to 10.33 per 100 000 inhabitants.

CONCLUSIONS

The trend of ADRs reporting has been increasing over the 19 years but is still low. This study showed a considerable underreporting of ADR, and about one of four detected ADRs were reported to the pharmacovigilance center from 1999 to 2017.