Website of Note: Study Design 101.

Abstract

http://himmelfarb.gwu.edu/tutorials/studydesign101/index.html Understanding research and published studies is crucial as the world moves toward an evidence-based approach to medicine and other scientific fields. However, for students beginning to learn about study types, differentiating between the various types and their strength of evidence can be confusing. The librarians at the Himmelfarb Health Sciences Library at The George Washington University sought to explain the basic types and differences between types in a way that would resonate with students. The result is the Study Design 101 site. Study Design 101 organizes the information in two ways; an evidence pyramid diagram and supplemental resources. The primary focus is on the evidence pyramid and guiding students from case reports at the bottom to meta-analyses at the top of the pyramid. Clicking on each of the seven study types in the pyramid diagram produces a more detailed page, focused on that particular study type. On these pages a definition of the study type is provided, along with advantages and disadvantages of the type as well as possible design pitfalls common to that type of study. Examples, both fictitious and from the medical literature, are included to allow students to deepen their knowledge of a particular study type. Links to specific relevant formulas (e.g. sensitivity/specificity, false positive and false negative rates, relative risk, odds ratio, etc.), and pertinent terms with definitions (e.g. blinding/masking, correlation, confounding, null hypothesis, etc.) are also included for each individual study type. Finally, a few multiple choice or true/false questions are presented so students can test their knowledge of the particular study type. Students can work through each level of the pyramid in sequence or alternatively, jump from one type to another by clicking on the various levels in the evidence pyramid. The full sets of supporting materials are also linked across the top of the site including a compilation of common formulas, a glossary of terms with definitions, and a video tutorial on finding various study types in Ovid MEDLINE. Averaging over 700,000 hits per year, Study Design 101 is freely available under a Creative Commons license (Attribution-NonCommercial-NoDerivs 3.0 Unported). The Study Design 101 site can be linked in online courses or course materials as long as credit is given to the creators. The content was reviewed in 2011 by a professor of Epidemiology and Biostatistics for accuracy before the site was released to the public, and the site is also reviewed and updated annually. Written in jargon-free language at a tenth grade reading level, Study Design 101 is approachable for undergraduate and graduate students in most disciplines. The simple format and explanatory content helps students develop their information literacy skills; an important proficiency in critically assessing primary research papers—one of the key curricular skills recommended by the American Society for Biochemistry and Molecular Biology for undergraduate biochemistry and molecular biology majors 1. Understanding how specific study designs can affect the strength of study results helps students to become better consumers of scientific material, as well as more informed creators when they are in a position to develop their own original research. This accessible approach to a challenging topic is one reason that Dr Ann Taylor decided to include the site in her undergraduate biochemistry course for non-science majors. In her course, Dr Taylor asks her students to evaluate medical claims made in the media. The Study Design 101 website is introduced in class, with a discussion about the evidence pyramid, the reasons for different study designs, and the advantages/disadvantages of each type. For homework the students are asked to search PubMed to find articles with specific study designs (e.g. case control, cohort, etc.) on a designated medical topic from the popular media. Each article is critically evaluated and students are then asked to support or refute the popular media's medical claim, based on their assessment of the professional literature. Students refer back to the Study Design 101 website for additional information about the various study types, as needed. Study Design 101 offers students plain language explanations of common study types with understandable examples, accessible online at any time. The site has proven popular with both students and faculty. Educators at multiple institutions have requested formal permission to include this resource in an online health sciences course, an evidence-based practice instructional module, a research toolkit for clinicians, and as part of lecture materials on study design for medical students. However, the Creative Commons license does not require permission to share or link to the site (as long as attribution is included), so it is possible the site has been integrated in additional instruction beyond these formal requests. This article offers a brief introduction to Study Design 101; additional information about Dr Taylor's instructional use of Study Design 101 is available in her companion article in this issue.