Liverpool ADR Causality Assessment (Gallagher 2011)
The Liverpool causality category for a suspected adverse drug reaction.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Do you suspect an adverse drug reaction?
- Yes
- Did the event appear after the drug was administered or dose increased?
- Yes
- Did the event improve when the drug was stopped or dose reduced?
- Yes
- What is the probability that the event was due to an underlying disease?
- Low
- Was there a positive rechallenge?
- No
- Is there a past history of the same event with this drug in this patient?
- No
- Has the event previously been reported with this drug?
- Yes
Result: Liverpool causality category: Probable.
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Do you suspect an adverse drug reaction?
- Did the event appear after the drug was administered or dose increased?
- Were pre-existing symptoms exacerbated by the drug?
- Did the event improve when the drug was stopped or dose reduced?
- Was the event associated with long-lasting disability or impairment?
- What is the probability that the event was due to an underlying disease?
- Was there a positive rechallenge?
- Is there any objective evidence supportive of the causal ADR mechanism?
The other 2 fields
- Were pre-existing symptoms exacerbated by the drug? (if it did not appear after the drug)
- Was the event associated with long-lasting disability or impairment? (if it did not improve)
- Was there a positive rechallenge? (if low)
- Is there any objective evidence supportive of the causal ADR mechanism? (if high or unsure)
- Is there a past history of the same event with this drug in this patient?
- Has the event previously been reported with this drug?
How this is calculated
Citation
Gallagher RM, Kirkham JJ, Mason JR, et al. Development and inter-rater reliability of the Liverpool adverse drug reaction causality assessment tool. PLoS One 2011;6(12):e28096, Figure 2 (CC BY). Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.