Examples of secondary data are research reports, government reports, censuses, weather reports, interviews, the Internet, reference books, organizational reports and accounting documents. Secondary data can be defined as information collected by someone other than the user. The use of secondary data helps researchers conserve resources (such as time and money) that the collection of primary data demands.
Other sources of secondary data are structured interviews, transcripts from focus groups, published texts, literature reviews and observation records. Records written and kept by individuals (such as diaries and journals) and accessed by other people are also regarded as secondary sources. In addition, databases that keep information about the public, such as electoral statistics, registers, social security and housing information, are secondary sources.
One major benefit of using secondary data is that it has already been reviewed by authorities and suitably used elsewhere. Most of the information has been accepted and approved for consumption by different audiences. On the other hand, researchers obtain primary data by personally interviewing the respondents. This may also involve going to the field to observe occurrences and recording the observations. The advantage to collecting primary data is that the questions asked are directly tailored to suit the needs of the researcher. In addition, one can ask follow-up questions for clarification, something that is practically impossible when using most secondary data.