An appendix contains supplementary material that is not an essential part of the text itself but which may be helpful in providing a more comprehensive understanding of the research problem and/or is information which is too cumbersome to be included in the body of the paper. A separate appendix should be used for each distinct topic or set of data and always have a title descriptive of its contents.
Your research paper must be complete without the appendices, and it must contain all information including tables, diagrams, and results necessary to address the research problem. The key point to remember when you are writing an appendix is that the information is non-essential; if it were removed, the paper would still be understandable.
It is appropriate to include appendices...
I. General Points to Consider
When considering whether to include content in an appendix, keep in mind the following points:
Appendices may include some of the following, all of which should be referred to or summarized in the text of your paper:
NOTE: Do not include vague or irrelevant information in an appendix; this additional information will not help the reader’s overall understanding and interpretation of your research and may only succeed in distracting the reader from understanding your research study.
Here are some general guideline on how to format appendices, but consult the writing style guide [e.g., APA] your professor wants you to use for the class, if needed:
Appendices. The Structure, Format, Content, and Style of a Journal-Style Scientific Paper. Department of Biology. Bates College; Tables, Appendices, Footnotes and Endnotes. The Writing Lab and The OWL. Purdue University; Lunsford, Andrea A. and Robert Connors. The St. Martin's Handbook. New York: St. Martin's Press, 1989.