At the other end of the spectrum are those interventions that have modest effects, if any at all. It is these interventions that require studies with rigorous design and of rigorous execution to determine whether an effect does indeed exist and to estimate its size.

The next section examines a variety of research methods available for use in conducting clinical effectiveness research.

Many factors can influence the outcome of treatment. These include the treatment itself, characteristics of the patient (such as age, gender, and comorbid conditions), other treatments, access to care, adherence to treatment plans, socioeconomic status and education, and the skill of the practitioner. In treatment effectiveness research, the goal is to evaluate the contribution of one of these factors, treatment, to determine whether treatment makes a difference. Doing so can be difficult if other factors are at play, as they often are. The goal of study designs is usually to make it possible to assess the contribution of the treatment after the other influences on outcome are taken into account.

In a study comparing two clinical interventions, the goal is to be sure that any difference observed is due to the differences in the two interventions rather than some other factor. The “some other factor” is a “confounder,” because it confounds one’s efforts to draw the conclusion that differences between the interventions are responsible for the differences in outcomes.

The best way to be sure that one can draw a strong conclusion from a difference in outcomes is to assign subjects randomly to receive one intervention or the other. If the randomization is successful and the number of patients is large enough, the two study populations will be essentially identical except for the different interventions. If one conducts the study so that, except for the intervention, the study populations are also identical at the end of the study, the researchers can make a very strong inference that the cause of the differences in outcomes is the difference in the interventions. Randomization is powerful because it ensures that the two populations are similar in every respect except for the intervention to which the researchers randomly assigned the patients. This claim means that if the study groups are large enough and the randomization was successful, the frequencies of

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)