Table 1.

Selection of the study sample

	Private drug plan	PDP
Filled prescriptions recorded in reMed between 1 January 2015 and 23 May 2019	3 188 963 prescriptions 38 064 patients	1 816 751 prescriptions 10 029 patients
Excluding filled prescriptions with drug cost or quantity equal to zero and invalid DIN or drug insurance number	2 629 317 prescriptions 33 441 patients	1 694 527 prescriptions 9 495 patients
Excluding prescriptions filled by patient 65 years old or more at the date of the last filled prescription	2 335 846 prescriptions 32 270 patients	558 273 prescriptions 6 244 patients
Excluding filled prescriptions inconsistency between cost and quantity dispensed	2 335 643 prescriptions 32 093 patients	557 675 prescriptions 6 187 patients
Strata of prescriptions based on DIN, quantity dispensed, number of days supplied, pharmacy identifier and RAMQ’s List of Medications	2 335 643 prescriptions 1 636 401 strata 32 093 patients	557 675 prescriptions 330 827 strata 6 187 patients
Matching strata of prescriptions filled by privately insured patients to strata of prescriptions filled by patients insured by the PDP (12 570 different patients in total)	100 809 prescriptions 38 896 strata 10 287patients	61 210 prescriptions 38 896 strata 3 599 patients