Which of the following is an example of secondary data source?

• A. A published review article that synthesizes findings from many studies.
• B. Data from your own experiment.
• C. A new survey conducted by you.
• D. An interview you conducted.

Answer: (A)

In research, secondary data are pieces of information that were collected by someone else for a purpose other than your current study, and you use or synthesize them rather than gathering new raw data yourself. A published review article fits this because it brings together and interprets findings from many original studies rather than presenting new data you collected. It relies on data that already exist in primary sources, and its value lies in synthesis, comparison, and overarching conclusions drawn from those prior studies.

The other scenarios involve data you collected directly for your own project—your own experiment, a new survey you conduct, and an interview you carry out. Those are primary data, since the information comes from your own procedures and participants.