Drug Safety

, Volume 31, Issue 4, pp 335–344 | Cite as

Improving the Reporting of Adverse Drug Reactions

A Cluster-Randomized Trial Among Pharmacists in Portugal
  • Maria T. Herdeiro
  • Jorge Polónia
  • Juan J. Gestal-Otero
  • Adolfo Figueiras
Original Research Article


Background: Adverse drug reaction (ADR) reporting systems are the basic component for comprehensive postmarketing surveillance of the risk of drug-induced adverse effects. The aim of this study was to evaluate the effectiveness of educational outreach visits aimed at improving ADR reporting by pharmacists.

Methods: The study population comprised all pharmacists working in a catchment area covered by Portugal’s Northern Regional Health Authority. Using unequal randomization, four spatial-clusters were assigned to the intervention group (n = 342) and eleven to the control group (n = 1091). The intervention took the form of 1-hour long educational outreach visits tailored to training needs detected in a previous study, with a 13- to 16-month follow-up period (March–June 2004 through June 2005). This study is registered as an international standard randomized controlled trial, number ISRCTN45 894687.

Results: At baseline, ADR reporting rates (per 1000 pharmacist-years) did not differ significantly between the intervention and control groups (32.28 vs 29.16). The adjusted increase in ADR reporting attributable to the intervention was 275.63 per 1000 pharmacist-years (95% CI 162.15, 389.12; relative risk RR] = 5.87, 95% CI 1.98, 17.39). The intervention succeeded in multiplying the reporting rate of: serious ADRs, 10-fold (RR = 9.79; 95% CI 2.24, 42.66); unexpected ADRs, 4-fold (RR = 4.41; 95% CI 1.11, 17.53); high-causality ADRs, 9-fold (RR = 8.67; 95% CI 2.12, 35.42); and new drug-related ADRs, 9-fold (RR = 9.33; 95% CI 2.53, 34.40). While the greatest effect was registered during the first 4 months post-intervention, differences remained statistically significant for 8 months.

Conclusions: Educational outreach visits improve ADR reporting by pharmacists in terms of quantity and relevance.


Educational Intervention Community Pharmacy Reporting Rate Community Pharmacist Hospital Pharmacist 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors wish to express their sincere thanks to the Program for the Educational Development in Portugal (PRODEP) for funding the study; all members of staff at the Northern Pharmacosurveillance Unit in Portugal; the National Association of Pharmacies; the Hospital Pharmaceutical Association; the pharmacists who took part in the intervention and Michael Benedict for his help with the English version of this paper. Professor Dr Adolfo Figueiras’ work on this project was in part funded by Health Research Fund (Fondo de Investigación Sanitaria) grants 99/1189 from the Spanish Ministry of Health, and by CIBER of Epidemiology and Public Health. The authors have no conflicts of interest that are directly relevant to the content of this study.


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Copyright information

© Adis Data Information BV 2008

Authors and Affiliations

  • Maria T. Herdeiro
    • 1
    • 2
  • Jorge Polónia
    • 3
  • Juan J. Gestal-Otero
    • 1
    • 4
    • 5
  • Adolfo Figueiras
    • 1
    • 5
  1. 1.Department of Preventive Medicine and Public HealthUniversity of Santiago de CompostelaSantiago de CompostelaSpain
  2. 2.Northern Polytechnic Health Institute (Cooperativa de Ensino Superior Politécnico e Universitário — CESPU)GandraPortugal
  3. 3.Northern Pharmacosurveillance Unit, Faculty of MedicineUniversity of PortoPortoPortugal
  4. 4.Preventive Medicine ServiceUniversity Hospital of Santiago de CompostelaSantiago de CompostelaSpain
  5. 5.CIBER en Epidemiología y Salud Pública (CIBERESP)MadridSpain

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