Table 3.

Outcomes of studies conducted to evaluate ADR reporting using interviews, questionnaires, or observers

Study	Country	Study type	Study period	Sample size	HCP targeted	Outcome	Statistical test	Conclusion
Somers29	Belgium	Prospective comparative study	9 months (Mar to Nov 1999)	168 patients and 56 patient interviews	Physicians Nurses Pharmacists	Comparing spontaneous reporting by physicians and nurses with patient interviews by pharmacists as methods for detecting ADRs	Spontaneous ADR reports (12): Nurses 4/168 patients (2.4%) Physicians 8/168 patients (4.8%) Causality of ADRs (n = 12) 75% probable; 25% possible Proportion of ADRs resulting in intervention 92%	Solicited techniques improved ADR reporting. The attributed causality % was similar for both groups. There were a higher proportion of ADRs resulting in intervention identified from spontaneous reports compared to patient interviews
							Patient interviews: 32 ADRs reported from 56 patient interviews Causality of ADRs (n = 32) 72% probable, 28% possible Proportion of ADRs resulting in intervention 59%
Aspinall27	US	Comparative study	2 months (Jan to Feb 2001)	198 patients	Physicians	Comparison of voluntary reporting of ADRs with telephone interviews to patients and providers in identifying ADRs	Patient and provider interviews identified total 83 ADRs in 51 patients (13% probable, 86% possible, 1% doubtful)	Telephone interviews identified a far higher proportion of suspected ADRs compared to the passive reporting system. Medical staff were unaware of nearly half the ADRs despite outpatient review within preceding 72 hours possibly due to time constraints
							Reporting rate 0.5% (1/198) vs 51/198 (26%) patient and provider interviews
							Majority (51%) were related to cardiovascular medications and 48% resulted in medication change
Greenhill28	US	Comparative study	Not stated	59 Interviews (95% by physicians and 5% by nurse practitioner	Physicians	Comparing number of adverse events (ADRs) reported by different questioning methods: general inquiry (GI); the drug-specific inquiry (DSI); or a comprehensive body system review (BSR)	Total adverse events 195 50 (26%) ADRs identified at GI (54% were moderate to severe) 16 (8%) additional ADRs identified at DSI (75% were moderate to severe) 129 (66%) additional ADRs identified at BSR. (37% were moderate to severe) Clinically relevant ADRs leading to medical action GI 15 (31%); DSI 2 (12%) BSR 19 (15%)	Systematic elicitation of ADRs organized by body systems, increased the identification of clinically relevant ADRs that may not be detected by general enquiry. However the study had low power, ADRs were not validated and was based on children using psychotropic medications only limiting generalizability