tion, which most often received a sham or a placebo treatment. If a clinical trial is designed and performed correctly, clinicians can use the results obtained with a limited number of participants to guide a treatment for an entire patient population (Matthew, 2001).

Phase I clinical trials are used to determine safety and an appropriate treatment dosage and regimen and, in some cases, are used to perform preliminary analysis of the biological activity of the intervention. Phase II and phase III clinical trials evaluate the efficacy of the new intervention and examine adverse effects in studies with larger populations. In the end, a novel drug that has entered a phase I clinical trial has only an approximately 30 to 40 percent chance of successfully completing a phase III clinical trial and being approved by the Food and Drug Administration (FDA) (Harding, 2004). Phase IV clinical trials are required by the FDA for additional analysis of long-term risks and benefits.

As described in Chapters 4 and 5, a range of approaches relating to the