A Guide to Scientific Writing Neal Lerner Marilee Ogren-Balkama Massachusetts Institute of Technology Introductions What’s an Introduction?  An introduction is a method to familiarize and orient your readers.  The content of an introduction depends on its purpose and the audience.  All models share a direct approach. Don’t hide your main point or save it until the end of the paper. What’s the Purpose of an Introduction in Scientific Writing?  Provide the context of your work (create your research space, define gap in knowledge, set up the direction you’ll take in your discussion section).  State your focus (hypothesis, question).  Provide justification for your work (how your work can answer the question). What are Some Common Pitfalls of an Introduction Section?  Including unnecessary background or being repetitive.  Exaggerating (or understating) the importance of your work.  Using lackluster openers and weak follow-through in the body of your introduction.  Not grounding the work in a context that will be important to your reader.  Not focusing on a clear and compelling research question or hypothesis. Guidelines for Introductions from Two Scientific OrganizationsFrom the International Committee of Medical Journal Editors: State the purpose of the article and summarize the rationale for the study or observation. Giveonly strictly pertinent references and do not include data or conclusions from the work beingreported.From the American Society for Microbiology: The introduction should supply sufficient background information to allow the reader to understand and evaluate the results of the present study without referring to previouspublications on the topic. The introduction should also provide the hypothesis that was addressed or the rationale for the present study. Use only those references required to provide the mostsalient background rather than an exhaustive review of the topic. Methods What are Some Goals of a Methods Section?  Present the experimental design.  Provide enough detail to allow readers to interpret your results. Cite as: Angela Belcher, Drew Endy, Natalie Kuldell and Agi Stachowiak. Course materials for 20.109 Laboratory Fundamentals in Biological Engineering, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY].Lerner & Ogren, A Guide to Scientific Writing p. 2  Give enough detail for readers to replicate your work.“The key to a successful Methods section is to include the right amount of detail--too much, and it begins to sound like a laboratory manual; too little, and no one can repeat what was done.” Successful Scientific Writing, 2nd ed. What are Some Pitfalls of a Methods Section?  Providing too little or too much information.  Reiterating published methods rather than citing them.  Writing strictly in chronological order (alternatives: most important first, most fundamental first, etc.).  Methods and results don’t correspond (you have to provide methods for all the experiments you report).  Forgetting to use visual organizers that direct readers to specific aspects of the methods section, e.g., subheads.  Using a “dangling modifier” because of an over-reliance on passive voice:“After scraping the desired plate in four swipes, the bacteria were placed in 8ml of mediawith no antibodies.”  Failing to provide a context for the methods themselves: “In order to . . . , we . . . “ ⇐ context for the particular method is provided.  Writing a Protocol rather than a Methods section.A Protocol is . . . A series of steps to be carried out. Written in sequential or temporal order. Intended for the reader to achieve a final result. A Methods Section is . . A series of steps already completed and is written in past tense. Written in logical order. Intended for the reader to replicate the experiment. Results What is the Purpose of the Results Section?  Objectivity: Make the data, just the data, easy to find.Some readers want to interpret your data themselves rather than accepting theinterpretation presented in the discussion.  Description: Describe the data presented in figures and tables. What Differentiates Results from the Methods?  Methods = How the data were accumulated.  Results = What data were accumulated. What Differentiates Results from the Discussion?  Results = Data presentation (“Experiments showed that . . . .”)  Discussion = Data interpretation (“Experiments suggest that . . . .”) Cite as: Angela Belcher, Drew Endy, Natalie Kuldell and Agi Stachowiak. Course materials for 20.109 Laboratory Fundamentals in Biological Engineering, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY].Lerner & Ogren, A Guide to Scientific Writing p. 3 What are the Contents of a Results Section?  A brief description of the experiment or rationale at the beginning of each subsection (“Inorder to . . . . As a result, we found that . . . .).  The data (in past tense).  Descriptive text for FEW determinations.  Tables or graphs for REPETITIVE determinations.  The data that your methods indicated you would produce (and answering the questions you established in your introduction). What are Some Qualities of a Well-Written Results Section?  Methods and Results Correspond. i.e., no experimental results for which there are no methods, and vice versa.  Results are presented in a logical order. e.g., most important first, most fundamental first, etc.  Results focus on the question(s) or hypothesis introduced earlier in the paper. What are Some Pitfalls of a Results Section?  Overstating the results (e.g., “Figure 1 clearly shows…”)  Reporting irrelevant results: Although it is sometimes useful to report experiments that didn’t work.  Omitting visual organizers, such as subheads.  Including inappropriate illustrations.  Including methods and/or discussion: Overlap is acceptable in some circumstances. Illustrations What’s the Purpose of Illustrations?  Condense large amounts of information  Convince readers of your findings (by showing data quality).  Focus attention on certain findings (e.g., relationship between values).  Simplify complex findings.  Promote thinking and discussion. Illustration Caveat: The most beautiful illustration cannot hide lousy