Christiansen CF, Pedersen L, Sorensen HT, Rothman KJ. Methods to assess seasonal effects in epidemiological studies of infectious diseases-exemplified by application to the occurrence of meningococcal disease. Clin Microbiol Infect. 2012 Oct 1;18(10):963-9.
Lash TL, Johansen MB, Christensen S, Baron JA, Rothman KJ, Hansen JG, Sorensen HT. Hospitalization rates and survival associated with COPD: a nationwide Danish cohort study. Lung. 2011 Feb 1;189(1):27-35.