http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
1 online resource (1 video file (00:02:16)) : sound, colour.
Billy Jack explains what a randomized controlled trial (RCT) is and its key features: being a controlled experiment that uses randomization to ensure a fair comparison between treatment and control groups.