Fig. 1 Schematic of method used to identify potential multidrug interactions (pMDIs) and associated potential adverse drug events (pADEs). Step 1: each drug-drug pair in the drug-drug interaction table from NYP was represented as a Set (A ) and numbered consecutively (Set A 1, Set A 2…) Step 2: a unique MED-LIST set (Set B ) was generated for each patient and included all the medications on the patient’s list. TheB sets of each patient’s medications list were numbered consecutively (Set B 1, SetB 2…). Step 3: For each SetA n in the DRUG-DRUG INTERACTION TABLE, we checked to see if it was a subset of the patient’s MED-LIST, SetB n. Step 4: Overlapping drug-drug pairs were identified using network analysis. Step 5: potential ADEs associated with pMDIs were identified by consulting the NYP drug-drug interaction table which includes a detailed description of adverse event associated with a particular drug-drug interaction.