[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Views 225
Citations 0
Comment & Response
April 2014

Bronchodilator Safety in Chronic Obstructive Pulmonary Disease—Reply

Author Affiliations
  • 1Division of Respirology, Department of Medicine, University Health Network, Toronto, Ontario, Canada
  • 2Division of Respirology, Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
  • 3Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
  • 4Division of Respirology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
  • 5Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada
JAMA Intern Med. 2014;174(4):648. doi:10.1001/jamainternmed.2013.12684

In Reply We thank Drs van Dijk and Käyser for their thoughtful comments on our study. They argue that our study design may be prone to residual confounding, despite our use of sophisticated methods to control for this. We agree and said so in our article.1 However, randomized trials are also prone to methodological limitations, particularly when attempting to assess harms of therapy, which observational studies can overcome. Specifically, randomized trials often exclude participants with comorbidities or demographic characteristics that would place them at increased risk of adverse events, even when such characteristics are common among patients who in clinical practice will go on to receive the treatments being evaluated. Also, as serious adverse events are typically infrequent and often unexpected, randomized trials commonly lack sufficient power to identify them adequately.

First Page Preview View Large
First page PDF preview
First page PDF preview