Certain precautions as mentioned below should be taken while using secondary data:
1. Reliability:
Before using secondary data, one should verify the level of reliability of the data. Data collected and published by government, semi-government or autonomous organisations are more reliable. The data collected by private organisations are less reliable because they collect the data to suit their own ideology or they might have some bias or prejudice present.
2. Purpose:
The purpose of collecting data should be properly examined before it is used as secondary data.
3. Method of collecting data:
The method of inquiry used in collecting data should be known. From the knowledge of method applied, one becomes familiar with its limitations also.
4. Time duration:
The time duration when the data was collected should be known because the data collected in remote past becomes irrelevant in the present circumstances.
5. Scope of data:
Before using secondary data, matters pertaining to scope of data, region for which the data are collected, definitions of terms used and the selection of units should be ascertained.
6. Limitations:
The limitation and drawbacks of the data should be known for the secondary data to be used.
7. Alternatives:
If alternative data are available, the data should be compared and then only proper data should be used as secondary data.
