He has worked in the area of epidemiology and public health for over 30 years and has over 80 publications in peer-reviewed journals and has published chapters in several books. He is one of the developers of Epi Info, a freely downloadable web-based software package for the analysis of epidemiologic data published by the Centers for Disease Control and Prevention. He is also the co-author of OpenEpi, a freely downloadable web-based calculator for epidemiologic data (www.OpenEpi.com).