principle.” After proof of principle, other studies may explore the size of the effect in different study populations, at different clinical sites, and under different conditions of practice. These are effectiveness studies.

Effectiveness studies evaluate the technology under real-world conditions of actual medical practice. The study population resembles that which one would see in day-to-day clinical practice, which means that any results are likely to apply to real-world clinical practice. Effectiveness studies have a greater chance of measurement error if the researchers have taken few precautions to standardize the measurements. Although measurement error reduces the precision of effectiveness studies, study populations are typically large, which increases the statistical precision.

Some researchers want to prove that their product is better than the standard product. If the new product is very effective, relatively small study populations may suffice to prove that the product is superior to the standard product. Often, however, researchers are content to show that their product is equivalent to the standard product. A typical situation is a minor chemical variation to a standard drug. The minor variation means that the patent on the standard drug does not apply, and the company making the new product can market it, as long as it is as good as the standard product. Thus, some studies are designed to prove noninferiority (the product is highly likely to be as good as the standard product). The designer of the trial tries to estimate the number of patients required to show that the two products do not result in clinically important differences in outcomes. One means to this end is to include enough subjects to be sure that the upper limit of the 95 percent confidence interval of the difference in outcomes (the largest difference that is reasonably possible) is slightly smaller than the minimum clinically important difference in outcomes. This technique almost guarantees that if the two products are truly equivalent, any difference actually observed between them in a particular study will be less than the smallest difference that clinicians would find meaningful. For all intents, the two interventions have equivalent effects.

Suppose one is investigating the relationship between eating a particular brand of breakfast cereal and subsequent myocardial infarction. The greater the intake of the cereal is, the greater the incidence of myocardial

Front Matter (R1-R22)

Executive Summary (1-12)

1 Introduction (13-33)

2 Prevalence, Cost, and Patterns of CAM Use (34-73)

3 Contemporary Approaches to Evidence of Treatment Effectiveness: A Context for CAM Research (74-107)

4 Need for Innovative Designs in Research on CAM and Conventional Medicine (108-128)

5 State of Emerging Evidence on CAM (129-167)

6 An Ethical Framework for CAM Research, Practice, and Policy (168-195)

7 Integration of CAM and Conventional Medicine (196-225)

8 Educational Programs in CAM (226-252)

9 Dietary Supplements (253-277)

10 Conclusion (278-282)

Appendix A: CAM Therapies, Practices, and Systems (283-292)

Appendix B: Consortium of Academic Health Centers for Integrative Medicine (293-294)

Appendix C: Table 1-1 List of Abbreviations (295-295)

Appendix D: Liaison Panel Organizations (296-297)

Appendix E: Model Guidelines for the Use of Complementary and Alternative Therapies in Medical Practice (298-306)

Appendix F: National Center for Complementary and Alternative Medicine Research Centers (307-309)

Appendix G: Public Meetings (310-318)

Appendix H: Committee Biosketches (319-326)

Index (327-338)