Figure.
Prevalence rates of smoking and percentage of mothers who quit smoking during pregnancy in a sample of mothers with children aged 0-15 (n = 30 667), National Health and Nutrition Examination Survey, United States, 1985-2014. Data source: National Center for Health Statistics, Centers for Disease Control and Prevention.13 Line indicates best-fitting line, and shading indicates mean 95% confidence intervals. Smoking cessation rate: percentage = –1164 + 0.603 year + e [R 2 = 0.36, N = 24], P = .002 (for birth year). Smoking rate: prevalence = 949.3 – 0.467 year + e [R 2 = 0.85, N = 28], P < .001 (for birth year).