What is meant by primary and secondary data? Discuss their merits and demerit.

Primary and secondary forms of data are classified on the basis of who has collected the data. Primary data is data personally collected by the investigator. It is raw data that has been collected firsthand by the researcher, using techniques such as experiments, questionnaires, interviews, and surveys. Secondary data, on the other hand, is that which has been collected by a different person but is used by a researcher in a given study to answer...

Primary and secondary forms of data are classified on the basis of who has collected the data. Primary data is data personally collected by the investigator. It is raw data that has been collected firsthand by the researcher, using techniques such as experiments, questionnaires, interviews, and surveys. Secondary data, on the other hand, is that which has been collected by a different person but is used by a researcher in a given study to answer certain questions. It is information that has already been collected, even analyzed, by another person and availed for public use via publications, journal articles, the internet or other reliable media.

Advantages of primary data

• Has a high degree of accuracy since the data is directly matched to the topic of study. The researcher is involved in the data collection process, hence is able to collect data that directly answer the questions of interest.


• Primary data is more current than secondary data.


• Should there be a need to, additional data that answers emerging questions may be collected within the period of study.

Disadvantages of primary data

• It can be an expensive method of data collection, in terms of time, effort and other resources. For instance, the method of data collection must be properly designed so that the collected data is representative of the population, in cases where sampling is done. This requires time, effort and money to achieve. Note that the larger the sample used, the more expensive is the process.


• Accuracy can be reduced in data collection methods such as surveys or interviews, when respondents fail to give accurate answers, perhaps due to poor design of the questions, or time issues or even a desire to give responses that are socially acceptable.


• There is a need for trained personnel who can appropriately use study guidelines during data collection in order to achieve required results.

Advantages of secondary data

• It is cheaper and faster to use.


• It helps to save on resources used in primary data collection, such as time, effort and money.

Disadvantages of secondary data

• Data accuracy and reliability is lowered since data specific to a different study is tailor-made to answer questions for a given study. Studies may have environmental or other differences that make comparison difficult.


• Secondary data may not be as recent as primary data.