Although an understanding of research methodology has been identified as an important skill for family practice researchers, the available literature contains confusing terminology and lacks agreement about research design classifications. A multidimensional taxonomy is presented to clarify and simplify the understanding of research designs, data collection methods, and research populations for family practice researchers. The taxonomy was used to classify 103 articles from five medical journals. Compared with general medical journals, reports in family practice journals used similar research designs but were more likely to rely on self-report data and to draw subjects from outpatient populations.