Schmidt M, Christiansen CF, Mehnert F, Rothman KJ, Sorensen HT. Non-steroidal anti-inflammatory drug use and risk of atrial fibrillation or flutter: population based case-control study. Br Med J. 2011 Jul 4;343:d3450. doi: 10.1136/bmj.d3450
McKenna SP, Doward LC. How should we measure quality of life in ankylosing spondylitis? Rheumatol Pract. 2008;6(2):12-4.