A cartoon to teach the need for a good control group in research studies. Cartoon by John Landers (www.landers.co.uk) in 2003 based on an idea from Dennis Pearl (The Ohio State University). Free to use in the classroom and on course web sites. The cartoon's caption is similar to one by American cartoonist Peter S Mueller that depicts a control group and an "out of control" group that was produced independently a few years before this one.