As explained earlier, secondary data are those which are already collected and used for some purpose by some one or more agencies and are again collected by another agency from any of these prior agencies rather than the original source for using them in a similar or different type of project. As such, there is no necessity of employing any of the methods of collection that are employed for investigation, appointment of local correspondents, mailing of the questionnaires, and sending the schedules through the enumerators.
However, for collecting the secondary data, the investigator has to contact the relevant sources of the secondary data in either of the following methods:
- Personal visit to the source
- Correspondence with the authorities of the source.
- Subscription to the periodicals.
Each of the above methods of collecting the secondary data is discussed briefly in the following paragraphs;
Personal Visit to the Sources.
Under this method, the investigator personally visits the sources of the information viz. libraries, museums, government offices, private and semi-govt. institutions, private persons like research scholars, MLAs, MPs etc., and requests the authority concerned to provide him with the necessary records and permit him to take down the required data therefrom. For this the investigator may be required to spend some time and make a vivid study at the source of the information. Investigators like research scholars and departmental officers of the government usually adopt this method. This method is comparatively more expensive and arduous in nature. But it takes a little time and gives more accurate and dependable results.
Correspondence with the Authorities of the Sources
Under this method, the investigator makes correspondence with the authorities of the relevant sources for getting the desired data by post or through some special messengers. For this, he writes very polite letters and reminders to the authorities concerned to supply him the necessary data for his study. He also appraises them of the need and importance of his study and seeks their cooperation in the matter. He also, assures them to return the data after his uses and to keep them secret if desired In this method, the data are collected usually in the form of reports, circulars, bulletins, statutes etc. This method of collecting the data is quite inexpensive and comfortable, provided the authorities of the sources are kind enough to extend their cooperation in time without any let up. However, this method of collecting the data may be very time taking and vexatious. The data obtained may not be adequate and appropriate in certain cases. At times, the investigator may be harassed and disappointed, if the authority of a source adopts an indifferent and discouraging attitude.
Subscription to the Periodicals
Under this method, the investigator subscribes to certain periodicals viz (Magazines, Journals, newspapers), regularly to obtain the relevant data therefrom. This method of obtaining the secondary data is, no doubt, very comfortable but all the same it is very much time taking and expensive. Moreover, the investigator may not get all the information from the periodicals to which he may subscribe. He has to seek for some other sources for the purpose. Thus, this method is inadequate to a particular institution or organisation, this method of collecting the secondary data may prove to be the best.