This study (a) compared maternal self-reports and database information on medication use, gestational age, date of delivery; (b) quantified the degree of agreement between sources; (c) assessed predictors of agreement.
Several studies compared self-reported and database information on medication use [ 17– 19], in specific subgroups, such as the elderly [ 20, 21], adolescents [ 22], hypertensive patients [ 16], or for specific medications or therapeutic classes, such as oral contraceptives [ 23], hormone replacement therapy [ 24], psychoactive medications [ 25], nonsteroidal anti-inflammatory drugs [ 26].
Health claims data on all patient encounters is collected for administrative purposes although in Ontario there is currently no centralized database on prescription medication.
In addition, the WHO Health Access/Action International database has data on medication availability.
The personal health number permitted electronic linking between all databases, allowing information on medication refills to be integrated with the patients' date of birth, gender, any record of hospitalisation, diagnostic test and specialist visit.
The identification of the patient given by the personal health number, cross-checked with the registry office, the hospital database and the diagnostic tests and specialist visits database allows the information on medication refills to be integrated with date of birth, sex, any record of hospitalization, diagnostic test, and specialist visit.
The dates of drug exposure were concurrently entered in the electronic database so the cumulative time on medication could be determined.
It is worth noting that the prescription database in GPRD can actually track data on medication prescribing better than many randomised controlled trials.
In 2011, a workshop on medication errors in safety databases was attended by ten national pharmacovigilance centres (Morocco, Kenya, Iran, New Zealand, Thailand, Spain, Switzerland, Nigeria, Brazil and Tunisia) and by patient safety organisations from the UK and Canada.
First, we relied on medication claims in the NHIRD database to define polypharmacy.
