Module 5: Secondary Data
How is Secondary Data Analysis Different from Primary Data Analysis?
Primary data is data that was collected by the researcher, or team of researchers, for the specific purpose or analysis under consideration. With primary data, a research team conceives of and develops a research project, collects data designed to address specific questions, and performs their own analysis of the data they collected. The people involved in the data analysis therefore are familiar with the research design and data collection process.
Secondary data analysis, however, is the use of data that was collected by someone else for some other purpose. In this case, the researcher poses questions that are addressed through the analysis of a data set that they were not involved in collecting. The data was not collected to answer the researcher’s specific research questions and was instead collected for another purpose.
Before deciding to collect your own data, determining what data are already available can be very valuable. Secondary data can be your only source of data or can be part of a mixed-methods design. Secondary data can be helpful in a needs or planning assessment. For example, in a project where you are conducting training on using biological controls to fight Brown Marmorated Stink Bug, it would be important to first determine the area with greatest number of farmers impacted by the pest, so you can then focus your training in places where you are likely to get a good turnout.