Data collection is an important part of carrying out research. How this data is collected and processed differs based on whether it is primary or secondary data, depending on the researcher.
You may have noticed some studies are conducted by the researchers themselves, which includes the collection of data and subsequent analysis of the data. In contrast, some researchers obtain data from other, previously conducted studies to further analyse the information.
Those conducting research may conduct a study and collect the data themselves or consult with other researchers to analyse their data.
Difference Between Primary and Secondary Data
Primary and secondary are both types of data. However, they differ in many key ways, such as:
- How the data is collected
- How is the data analysed
- The merits and demerits of both types of data.
Whether a researcher uses primary and/or secondary data is usually determined by the availability of the information and the research design that will be used in the study.
Primary and Secondary Data
Primary data is usually collected from the source, the participant, by the researcher conducting the study.
Primary data is defined as data that the researcher collects themself using their own experiment or through observing first-hand. It is also original data.
Secondary data is defined as data that the researcher has not collected themself. This can take the form of previously published findings, previous medical records or, diaries. Secondary data is previously collected information about the source.
Secondary data is usually collected when the researcher cannot collect data at the time of the study. This is because the study may investigate a past event, such as a historical event, and information may not be readily available.
A meta-analysis summarises previously published results to identify if the majority of the research supports or disproves the proposed hypothesis and is an example of secondary data.
Methods of Data Collection: Primary and Secondary Data
The methods of data collection of primary data that are commonly used are:
- Experiments or first-hand observations
- Interviews
- Questionnaires
- Psychometric tests
Psychometric tests are types of assessments that are used to measure various things such as talents, skills and personality.
The methods of data collection of secondary data that are commonly used are:
- Government statistics
- Diaries/personal letters
- Newspapers
- Memoirs/ autobiographies
- Previous research
Previous research is research that has been published by other researchers. This data collection method is usually used by researchers when carrying out a meta-analysis or systematic review.
Primary Data and Secondary Data Examples
The following research scenario gives primary and secondary data examples of how both types of data may be collected when conducting research.
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