The Secondary data is that specific data that has been already collected by the primary sources and made the data readily available for other researchers to use for their own research study. This is a type of data that has been previously collected and is further used by the required study.
A researcher might collect this data for a specific project, then after this, it is made available to be used by another researcher. The data in its primary form may also have been collected for general use with no specific research purpose like in the case of a national census.
This is the case when the primary data is being reused.
Limitations of Secondary Data
There are limitations involved in the usage of Secondary Data. The limitations are as follows:
The data which is being collected through the secondary sources may not be as authentic as if using the primary data which gives first-hand information when collected directly from the source.
The Researchers do spend a lot of time searching for many irrelevant data before finally bumping into the relevant one.
In cases like this, a researcher may not find the exact data he or she needs, but have to settle for the next best alternative, which might not be totally relevant.
These data sources are known to be exaggerated as the information which is being shared may be biased to maintain a good public image or due to a paid advert.
Some of the data sources are really outdated and thus there are no new available data to replace the old ones. For example, the national census is not usually updated yearly, and hence, this may lead us to outdated information about a particular study.
Precautions to be taken before using Secondary Data
The investigator is required to take adequate precautions before using the secondary data. For this, the following precautions should be taken into account.
Suitable Purpose of Investigation
The investigator must ensure that the data are quite suitable for the purpose of inquiry or his study.
Adequacy of the data is needed to be judged in the light of the requirements of the survey and also the geographical area covered by the available data.
Definition of Units
The investigator must also ensure that the definitions of the units are used by him are the same as in the same investigation.
Degree of Accuracy
The investigator is required to keep in mind the degree of accuracy that is maintained by each investigator.
Time and Condition of Collection of Facts
This is to be ascertained that before making use of the available data to the period and conditions, the data is to be collected.
The investigator should keep in mind whether the secondary data is reasonable, consistent, and comparable to his required study or not.
The use of the secondary data must do the test checking appropriately and see that the totals and rates are correctly calculated.
It is not safe to take the published statistics at their face value without knowing their means, values, and limitations which might be irrelevant totally.
Sources of Secondary Data
The sources of secondary data include books, personal sources, using the journal, reading the newspaper, website surfing, government record, etc. Secondary data are known to be readily available compared to that of the primary data. This requires very little research and need for manpower to harness these sources.
With the advent of electronic media and the internet, secondary data sources have become even more easily and readily accessible. Some of these sources are highlighted below-