Methods and Materials, Results, and Discussion Sections

Note: First familiarize yourself with the names for the kinds of scientific writing and with the names given the traditional parts of a scientific article on the page titled "Types of Natural Sciences Writing."   Write the article's sections in proper order--see "General Advice..." at the end of that page. Then consult this "cookbook" to get instructions for creating the four most difficult parts of the article so they will do what a scientific reader expects them to do. As you write, turn to the section you are working on and make sure it follows these instructions in the order they are given.

INTRODUCTION:  The Introduction answers the questions: what?; why?; and how? ("Who?" and "where?" and "when?" are identified on your title page by your name, course, and date.)

Teach the reader about your subject:

1) Define the subject, describing characteristics of the animal, plant, organ, structure, chemical, etc. you will study and explaining those characteristics' importance. As you do, mention pertinent literature that discusses previous research on your subject.

2) Describe the controversy or question which requires you to perform this experiment, referring to the literature mentioned in #1 above.

3) State how your experiment addresses this question or controversy (your purpose).

4) Finish with the major finding of your report, in one sentence if possible.

MATERIALS AND METHODS: The Materials and Methods section describes the essential stages of procedure necessary to reproduce this experiment.

Tell the reader how to repeat your experiment:

1) Explain the source of chemicals and/or animals

2) Explain your "experimental design," including the number and types of animals, quantities and concentrations of chemicals, make and model of unusual equipment, essential conditions (heat/cold, time, agitation or other stimuli).

3) Explain procedures used to measure effects you studied (e.g., the assay protocol, etc.).

RESULTS:  The Results section reports, without conclusions or discussion, specific effects the Materials and Methods said you were looking for (Materials and Methods #3).

Tell the reader what you found, dividing results of complicated experiments into types and reporting each type of result in a separate paragraph:

1) Open each Results paragraph with one general sentence stating the part of the procedure used to see the result described in that paragraph (should correlate with #3 in Materials and Methods).

2) State relevant results seen in this procedure, specifying both qualities (e.g., redness) and quantities (e.g., drops per minute). Use words and phrases like "greater," "lesser," "increased with time," "the majority," "less than 50%" to specify general trends in your results.

3) Many results include so many numbers that it is better to present this data in table or graph form. Summarize major trends in words (as in #2 above) but do not repeat actual numbers. Refer readers to the table, graph, or figure after your summary sentence: "Blood pressure is correlated with body weight (Figure 1) and age (Table 1)."

DISCUSSION: Your Discussion explains what the results show and interprets what they mean for the question or controversy which motivated the experiment (Introduction #2 and #3).

For each result reported in Results, explain what the result shows or means:

1) Open your Discussion by restating the question addressed by your experiment (see Introduction #2).

2) Match each paragraph in Results with a paragraph in Discussion. Open each paragraph with a 1-sentence summary of the procedure and result obtained (Results #1 & #2). Follow with a conclusion that can be drawn from the result. Use words and phrases like: "therefore" and "this result shows that" when conclusions follow directly, without interpretation, from the result; "this result suggests that" and "this result supports the conclusion that" when the results are not sufficient in themselves to confirm conclusions. If you found articles in scientific literature that support or contradict your findings, mention their findings here and explain how they affect your conclusions.