Secondary Data


Secondary data is the data that was collected in the past through primary sources and made available to researchers to use in their research. Secondary data are more easily available than primary data. These data can be the result of a researcher’s research or data for general use without research purposes, such as census data.

Sources of Secondary Data:

Due to the presence of the Internet and electronic media, secondary data are easily available, such as books, articles, magazines, newspapers, websites, blogs, government records (such as census data), podcasts, etc.

Secondary data collection tools:

-Robots or Software Robots are secondary data collection tools that are designed by programmers and collect relevant online data from the Internet.

-Devices equipped with the Internet, such as smartphones, laptops, and tablets that have access to the Internet, are other tools for collecting data from magazines, books, blogs, etc.

-The library is a traditional data collection tool. The researcher can be present in the library or borrow the books and return them to the library after collecting the required data.

-Radio channels that can be accessed via radio (and smartphones).

Secondary data analysis:

Researchers use secondary data to save time and resources used in primary sources. The process of secondary data analysis can be done quantitatively or qualitatively, depending on the type of data. In the quantitative analysis method, numerical data and mathematical methods are used to analyze the data. In the qualitative method, words are analyzed to provide in-depth information about the data.


Ease of access, low cost, saving time, and the ability to conduct longitudinal and comparative studies and create new insight into the subject (discovering a new point that the primary data researcher did not achieve) are significant advantages for secondary data collection.


Some limitations of this method are as follows:

  • Data quality: Because the content being shared is not monitored, secondary data may not be as valid as data collected directly from the sources.
  • Irrelevant data: The researcher may not be able to access the data he needs and therefore, spend a lot of time on finding alternatives for data.
  • Exaggerated data: Some sources (such as blogs) may provide exaggerated information to gain more traffic, and using these sources will exaggerate the research data.
  • Old data: sometimes there is no new data for the subject, for example, the census is not carried out annually, and therefore the demographic changes of the country may be ignored.