Meyers J, Classi P, Wietecha L, Candrilli S. Economic burden and comorbidities of attention-deficit/hyperactivity disorder among pediatric patients hospitalized in the United States. Child Adolesc Psychiatry Ment Health. 2010 Dec 1;4:31.
Cole JA, Rothman KJ, Cabral HJ, Zhang Y, Farraye FA. Incidence of IBS in a cohort of people with asthma. Dig Dis Sci. 2007 Feb 28;52(2):329-35.