%0 Journal Article
%T Accuracy of the days＊ supply and the number of refills allowed recorded in Qu谷bec prescription claims databases for inhaled corticosteroids
%A Am谷lie Forget
%A Anne Vilain
%A Catherine Lemi豕re
%A Fatima-Zohra Kettani
%A Francine M Ducharme
%A Genevi豕ve Lalonde
%A Lucie Blais
%A Marie-France Beauchesne
%J -
%D 2014
%R 10.1136/bmjopen-2014-005903
%X Objectives and hypotheses Adherence to inhaled corticosteroids (ICS) is a major issue in asthma. This study aimed to estimate the accuracy of the days＊ supply and number of refills allowed, variables recorded in Qu谷bec claims databases and used to estimate adherence, and to develop correction factors, if required. We hypothesised that the accuracy of the days＊ supply for ICS would be low whereas the accuracy of the number of refills allowed would be high.

Setting 40 community pharmacies in Qu谷bec (Canada) and a medication registry.

Participants We collected data for 1108 ICS original prescriptions stored in the 40 pharmacies (sample 1), and we obtained a second sample of 2676 ICS prescriptions selected from reMed, a medication registry (sample 2).

Primary and secondary outcomes We estimated the concordance of the days＊ supply and number of refills between Qu谷bec claims databases and the original prescription from sample 1. We developed a correction factor for the days＊ supply in sample 1 and validated it in sample 2. Analyses were stratified by age: 0每11 and 12每64ˋyears.

Results In sample 1, the concordance for the days＊ supply was 39.6% (95% CI 37.6% to 41.6%) in those aged 0每11ˋyears and 56% (54.9% to 57.2%) in those aged 12每64ˋyears. The concordance increased to 59.4% (58.2% to 60.5%) in those aged 0每11ˋyears and 74.2% (73.5% to 74.9%) in those aged 12每64ˋyears after applying the correction factors in sample 2. The concordance for the refills allowed was 92.1% (91% to 93.1%) in those aged 0每11ˋyears and 93.1% (92.5% to 93.7%) in those aged 12每64ˋyears in sample 1.

Conclusions The accuracy of the days＊ supply was moderate among those aged 0每11ˋyears and substantial among those aged 12每64ˋyears after applying the correction factors. The accuracy of the number of refills was almost perfect in both groups
%U https://bmjopen.bmj.com/content/4/11/e005903