This is a straightforward textbook to help beginners think through what is possible in a clinical research project. The chapters deal with "Causal Inference," "Reviewing a Published Study," "Learning the Language of Clinical Research," "Single-Subject Design," "Descriptive Studies," "Community-Based Cross-Sectional Studies," "Longitudinal Studies," "Case-Control Studies," "Clinical Trials," "Diagnostic Tests and Screening Instruments," "Population Genetics Studies," and "Analysis of Clinical Community Research and Data." The authors provide thoughtful and experienced comments on all of these subjects, and their text should be of particular help to beginners. The authors focus primarily on "clinical research in which the patient (or subject) is the unit of analysis" (p. viii).