Why are there deadly drugs?

Lack of essential information in spontaneous reports of adverse drug reactions in Catalonia-a restraint to the potentiality for signal detection

PURPOSE

The aim of this study is to analyze the quality of the information contained in the adverse drug reactions (ADR) reports and to describe the magnitude and characteristics of the lacking information.

METHODS

All reports of serious ADR received by the Catalan Center of Pharmacovigilance in 2014 were analyzed using the VigiGrade and a more clinical and qualitative approach.

RESULTS

Up to 824 reports describing serious ADR were included in the study; of them, 503 (61.0%) were sent by health care professionals (HPs) and the remaining 321 (39.0%) came from pharmaceutical companies (PhC). More than 80% of missing variables such as 'onset date' or 'time-to-onset' of the ADR were from PhCs reports. 'Onset of treatment date' was not filled in 28 (22.2%) of the reports including an 'additional monitoring' medicine, and 'end of treatment' date was not completed in 53 of those reports (42.1%). In summary, 39% of the reports involving a black triangle medicine sent by PhCs lacked some essential information such as the onset date of treatment.

CONCLUSIONS

More than one third of the reports coming from manufacturers did not include information that is considered a limiting factor to evaluate any causal relationship, and can be an issue for the detection of safety signals. To take advantage of this huge amount of potentially important information that is almost useless at present, data mining tools and new algorithms should be developed and tested with the aim of finding formulas to deal with a huge amount of low quality data without losing it, nor generating a number of false associations.

A 'reluctant' critical review: 'Manual for evidence-based clinical practice (2015)'

BACKGROUND

The Users' Guides to the Medical Literature Manual has been a major influence on the teaching and practice of health care globally.

METHODS

The 3rd edition of the multi-authored Manual was reviewed using the principles outlined in Evidence-based Medicine (EBM) texts. One 'clinical scenario' was selected for critical appraisal, as were several chapters; objectivity was enhanced by citing references to support opinions. RESULTS (SUMMARY OF THE APPRAISAL): (1) Strengths: Clinical pearls, too numerous to list.

EXAMPLES

(i) evidence is never enough to drive clinical decision making; (ii) do not rush to adopt new interventions; and (iii) question efficacy data based only on surrogate markers. (2) Weaknesses: The Manual shares shortcomings of textbooks discussed by Straus et al.: (i) references may not be current, important ones may be excluded and citations may be selective; (ii) often, opinion-based; and (iii) delays between revisions. (3) Notable omissions: Little or no discussion of: (i) important segments of the population: those <18 years of age, >65 years of age and those with multimorbidity; (ii) surgical disciplines; (iii) Greenhalgh et al.'s essay on EBM; (iv) alternate views on the hierarchy of evidence; and (vi) critical thinking. (4) Additional issues: (i) Omission of important references on dabigatran (clinical scenario: chapter 13.1); (ii) authors' advice (Chapter 13.3) to 'bypass the discussion section of published research'; and (iii) the advocacy of pre-appraised sources of evidence and network meta-analysis without warnings about limitations, are critiqued.

CONCLUSION

The Manual has several clinical pearls but readers should also be aware of shortcomings.