Kurth, Laura, and Eva Hnizdo. 2015. “Change in Prevalence of Restrictive Lung Impairment in the U.S. Population and Associated Risk Factors: The National Health and Nutrition Examination Survey (NHANES) 1988–1994 and 2007–2010”. Multidisciplinary Respiratory Medicine 10 (1). https://doi.org/10.4081/mrm.2015.281.