Interpreting Experiment Results

A typical experimental format involves evaluating the response caused by application of alternative treatments t o experimental subjects (animals, carcasses, pens, pastures, etc.). The effect of a given treatment might be evaluated by comparison t o a control group or to one or more other treatment groups. However, a problem wi th animal research (and other types as well) is that variation not due t o treatments often exists among experimental subjects. Statistical procedures can be useful to determine the extent to which observed variation is due to treatment effects versus other factors.