Causality assessment

The evaluation of the likelihood that a medicine was the causative agent of an observed adverse reaction.
Causality assessment is usually made according established algorithms.

Methods of causality assessment:

• WHO assessment scale
• Naranjo’s scale
• European ABO system
• Karch and Lasagna’s scale
• Kramer scale
• Bayesian network
• Yale Algorithm
• Spanish Imputation System

WHO Causality categories:

1. Certain
2. Probable
3. Possible
4. Unlikely
5. Conditional/Unclassified
6. Unassessable/Unclassifiable.

Reference: WHO