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Published on: December 9, 2015
Development of an indicator of smoking status for people with multiple sclerosis in administrative data
Ruth Ann Marrie1, Qier Tan, Okechukwu Ekuma2
1Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada.
Background:
Administrative data lack health behavior information.
Methods:
We developed an administrative case definition for past or current ('ever smoking') in 1320 individuals with MS from Manitoba, Canada. Candidate indicators for 'ever smoked' included smoking cessation medications, and diagnosis codes for tobacco use and chronic obstructive pulmonary disease, using variable lookback periods.
Results:
When compared to self-reported smoking status, the case definition incorporating all indicators over a lifetime lookback period had a sensitivity of 31.98%, and positive predictive value of 78.26%.
Conclusion:
This smoking status definition could only partially control for confounding due to smoking because of the low sensitivity.
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