enable readers to evaluate the work performed and (2) permit others to replicate your study.
In the Materials and Methods section you explain clearly how you conducted your study
in order to: (1) enable readers to evaluate the work performed and (2) permit others to replicate your study.
You must describe exactly what you did: what and how experiments were run, what,how much, how often, where, when, and why equipment and materials were used. The main consideration is to ensure that enough detail is provided to verify your findings and to enable the replication of the study.
You should maintain a balance between brevity (you cannot describe every technical issue) and completeness (you need to give adequate detail so that readers know what happened).
This should be the easiest section to write.
1. Order your procedures chronologically or by type of procedure and then
chronologically within type of procedure using sub-headings, where appropriate, to
clarify what you did. It is up to you to decide what order of presentation will make the most sense to your reader.
2. Use the past tense and the third person to describe what you did. For example: “The sample was incubated at 37ºC for 3 days.” – NOT: “I incubate the sample at 37ºC for 3
days.”
3. Describe your experimental design clearly, including the hypotheses you tested,
variables measured, how many replicates you had, controls, treatments, etc.
4. Explain why each procedure was done. Reference may be made to a published
paper as an alternative to describing a lengthy procedure.
5. Identify the source of any specific type of equipment, a specific enzyme, organism,
or a culture from a particular supplier, which is critical to the success of the experiment.
6. Describe in detail any modifications to equipment or equipment constructed
specifically for the study and, if pertinent, provide illustrations of the modifications.
7. Precisely quantify measurements (all metric) and include errors of measurement.
8. Describe the dates and the site where your field study was conducted including
physical and biological characteristics of the site, if pertinent to the study’s objectives.
9. Identify treatments using the variable or treatment name, rather than an ambiguous, generic name or number (e.g., use “healthy donors” rather than “group 1”).
Other points to consider when writing the Materials and Methods:
1. Don’t mix results with procedures.
2. Omit all explanatory information and background – save it for the discussion.
3. Don’t include information that is irrelevant to the reader, such as what color ice
bucket you used, or which individual logged in the data.
Dependent Variable
The variable that depends on other factors that are measured. These variables are expected to change as a result of an experimental manipulation of the independent variable or variables. It is the presumed effect.
Independent Variable
The variable that is stable and unaffected by the other variables you are trying to measure. It refers to the condition of an experiment that is systematically manipulated by the investigator. It is the presumed cause.
The process of examining a research problem in the social and behavioral sciences is often framed around methods of analysis that compare, contrast, correlate, average, or integrate relationships between or among variables. Techniques include associations, sampling, random selection, and blind selection. Designation of the dependent and independent variable involves unpacking the research problem in a way that identifies a general cause and effect and classifying these variables as either independent or dependent.
The variables should be outlined in the introduction of your paper and explained in more detail in the methods section. There are no rules about the structure and style for writing about independent or dependent variables but, as with any academic writing, clarity and being succinct is most important.
After you have described the research problem and its significance in relation to prior research, explain why you have chosen to examine the problem using a method of analysis that investigates the relationships between or among independent and dependent variables. State what it is about the research problem that lends itself to this type of analysis. For example, if you are investigating the relationship between corporate environmental sustainability efforts [the independent variable] and dependent variables associated with measuring employee satisfaction at work using a survey instrument, you would first identify each variable and then provide background information about the variables. What is meant by “environmental sustainability”? Are you looking at a particular company [e.g., General Motors] or are you investigating an industry [e.g., the meat packing industry]? Why is employee satisfaction in the workplace important? How does a company make their employees aware of sustainability efforts and why would a company even care that its employees know about these efforts?
Identify each variable for the reader and define each. In the introduction, this information can be presented in a paragraph or two when you describe how you are going to study the research problem. In the methods section, you build on the literature review of prior studies about the research problem to describe in detail background about each variable, breaking each down for measurement and analysis. For example, what activities do you examine that reflect a company’s commitment to environmental sustainability? Levels of employee satisfaction can be measured by a survey that asks about things like volunteerism or a desire to stay at the company for a long time.
The structure and writing style of describing the variables and their application to analyzing the research problem should be stated and unpacked in such a way that the reader obtains a clear understanding of the relationships between the variables and why they are important. This is also important so that the study can be replicated in the future using the same variables but applied in a different way.
