Primary research is designed, performed, and evaluated by the person using the collected data. For example, someone who observes the traffic patterns at a particular intersection, analyzes and organizes that data, draws conclusions from that data, and then presents the data in some final form is using primary research.
Secondary research is performed by another person. For example, secondary market research is, according to the website Entrepreneur, "Market research that's already compiled and organized for you. Examples of secondary information include reports and studies by government agencies, trade associations or other businesses within your industry." Secondary research is more common in research articles than primary research.
The principal advantage of writing a primary research article is that it can lend credibility to the claims you make in an article by showing the reader that you have invested time and energy in the subject. Also, conducting primary research allows control of what information is collected, in order to address specific issues or reduce spending (of time or money) for information. Furthermore, primary research presented in an article becomes the intellectual property of the writer.
Primary research can take a lot of time to conduct. Primary research may be subject to intense scrutiny to determine whether the research performed and the data derived are valid or useful. The validity of an article written with primary research as its support is going to depend greatly on the quality of the research. One serious risk of conducting primary research is that it may not always be feasible; some research projects are not within the resources of the researcher.
Examples of primary research include interviews, questionnaires, surveys, observations, and tests. Again, the biggest risks of using primary research are that sufficient research may not be within the time or monetary resources of the researcher and that the research may not produce valid results. If you undertake primary research, be sure to select your subject carefully and seek consultation with experts in the field before beginning the project.