Secondary sources of data have been described as those items that are original to the problem under study and may be thought of as being in two categories: first, the remains or relics of a given period; second, those items that have had a direct physical relationship with the events being reconstructed

The sources of data should be fully described, whether they be documents, settings that were observed, people interviewed or people who completed scales, tests or questionnaires.

Organizational evaluation is concerned with research that helps to clarify certain dimensions of organizations such as their capacity and their performance. The whole organization is the unit of analysis in such research which can effectively produce an evaluative case study of the organization.

Correlational methods attempt to understand and bring meaning to particular phenomena in a given environment.

The methodology section of a research proposal or report of a completed study should include reference to appropriate elements from those that follow.

Sources of data in historical research may be classified into three main groups: primary, secondary and historical sources.

Historical research in education can also show how and why educational theories and practices developed. It enables educationalists to use former practices to evaluate newer, emerging ones.

A review of literature is a summary, analysis, and interpretation of the theoretical, conceptual and research literature related to a topic or theme.

1.    A secondary source is an article that describes original research conducted by the author of the article. 

Nonempirical sources are more likely to discuss the general issues related to a topic whereas empirical sources are more likely to describe the groups studied and the methods used in the study (e.g., surveys, observations)