Comparison of the Liverpool Causality Assessment Tool vs. the Naranjo Scale for predicting the likelihood of an adverse drug reaction: A retrospective cohort study.

The Liverpool Causality Assessment Tool is a more sensitive tool than the Naranjo Scale in the assessment of possible ADRs, but both tools have poor SP. The Liverpool Tool can be a useful screening tool in settings where other tests may not be readily available. However, the low PPV and NPV of both tools suggest that to pursue further testing is needed to confirm or deny an ADR.