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Review
. 2008 Feb 12;178(4):425-7.
doi: 10.1503/cmaj.071592.

Mortality benefit from unrestricted access to clopidogrel: too good to be true?

Affiliations
Review

Mortality benefit from unrestricted access to clopidogrel: too good to be true?

Samy Suissa. CMAJ. .
No abstract available

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Figures

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Figure 1: Immortal time in the study by Sheehy and colleagues of restrictive access to clopidogrel. Patients were grouped as follows: those with a delay of at least 1 day between filling a nonrestrictive cardiovascular drug (NRCD) prescription and a clopidogrel prescription; those who did not fill a clopidogrel prescription despite filling a nonrestricted cardiovascular drug prescription; and those who filled both prescriptions without a delay. The time between cohort entry (percutaneous coronary intervention [PCI]) and the first nonrestricted cardiovascular drug prescription (blue line) is immortal for all 3 groups because the patients must have been alive during these periods to have filled their prescriptions. The time between the nonrestricted cardiovascular drug and clopidogrel prescriptions (orange line) is also immortal for those with a delay in filling a clopidogrel prescription. Patients who died during this period were necessarily grouped with those who did not fill a clopidogrel prescription.

Comment on

References

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