Methods for evaluating adverse drug event preventability in emergency department patients

Abstract

BackgroundThere is a high degree of variability in assessing the preventability of adverse drug events, limiting the ability to compare rates of preventable adverse drug events across different studies. We compared three methods for determining preventability of adverse drug events in emergency department patients and explored their strengths and weaknesses.MethodsThis mixed-methods study enrolled emergency department patients diagnosed with at least one adverse drug event from three prior prospective studies. A clinical pharmacist and physician reviewed the medical and research records of all patients, and independently rated each event’s preventability using a “best practice-based” approach, an “error-based” approach, and an “algorithm-based” approach. Raters discussed discordant ratings until reaching consensus. We assessed the inter-rater agreement between clinicians using the same assessment method, and between different assessment methods using Cohen’s kappa with 95% confidence intervals (95% CI). Qualitative researchers observed discussions, took field notes, and reviewed free text comments made by clinicians in a “comment” box in the data collection form. We developed a coding structure and iteratively analyzed qualitative data for emerging themes regarding the application of each preventability assessment method using NVivo.ResultsAmong 1356 adverse drug events, a best practice-based approach rated 64.1% (95% CI: 61.5–66.6%) of events as preventable, an error-based approach rated 64.3% (95% CI: 61.8–66.9%) of events as preventable, and an algorithm-based approach rated 68.8% (95% CI: 66.1–71.1%) of events as preventable. When applying the same method, the inter-rater agreement between clinicians was 0.53 (95% CI: 0.48–0.59), 0.55 (95%CI: 0.50–0.60) and 0.55 (95% CI: 0.49–0.55) for the best practice-, error-, and algorithm-based approaches, respectively. The inter-rater agreement between different assessment methods using consensus ratings for each ranged between 0.88 (95% CI 0.85–0.91) and 0.99 (95% CI 0.98–1.00). Compared to a best practice-based assessment, clinicians believed the algorithm-based assessment was too rigid. It did not account for the complexities of and variations in clinical practice, and frequently was too definitive when assigning preventability ratings.ConclusionThere was good agreement between all three methods of determining the preventability of adverse drug events. However, clinicians found the algorithmic approach constraining, and preferred a best practice-based assessment method.Electronic supplementary materialThe online version of this article (10.1186/s12874-018-0617-4) contains supplementary material, which is available to authorized users.

Characterization and preventability of adverse drug events as cause of emergency department visits: a prospective 1-year observational study

“…A recent study compared different methods for determining preventability ADEs in EDs claiming that a "best practice-based" preventability assessment was to be preferred by clinicians over an "algorithm-based" approach like the modified Schumock and Thornton criteria. The "best practice-based" approach required in any case a high level of clinical experience and expertise to assess an overall preventability ADEs [61]. Nevertheless, pharmacists or physicians were involved in our study, as monitors in EDs, to help ED physicians in obtaining medication histories, monitoring polypharmacy, and collecting additional information for causality and preventability assessment and to develop this critical component of patients' interview.…”

Preventable adverse drug events: Descriptive epidemiology

“…It was often difficult to assess the preventability of an event without knowing the exact circumstances of the care that had been provided, or the patient's perspective. Individual and professional biases may have affected how reviewers perceived the preventability of an event . Not all contributing factors were explicitly documented in the research or medical records, and therefore, undoubtedly, our clinical judgement, the patient's prior history, and documentation of the event's resolution informed our assessments.…”

“…reviewed the medical and/or research records of all patients diagnosed with one or more adverse drug events, and independently assessed each event's preventability. Events were categorized as definitely, probably or not preventable . If preventability ratings were discordant, reviewers discussed the case until reaching consensus, and a third reviewer adjudicated all cases in which consensus was not easily achieved.…”

“…Events were categorized as definitely, probably or not preventable. 30 If preventability ratings were discordant, reviewers discussed the case until reaching consensus, and a third…”

“…Based on our findings from previous work, we considered adverse drug events as preventable when there was "lack of adherence to best medical practice, including inappropriate drug, dosage, route or frequency of administration of a drug for the patient's clinical condition, age, weight or renal function; administration of a drug despite a known allergy, a previous adverse reaction to, or a drug interaction; non-adherence; laboratory monitoring not or inappropriately performed; prescribing or dispensing errors, or errors in drug administration." 30 We defined contributing factors as any patient-, provider-or system-level factors that our reviewers deemed instrumental to the development of the event.…”