Epistemology is a branch of philosophy that deals with the theory of knowledge and how knowledge is gathered and from which sources. In research, epistemology is concerned with the validity, scope, and methods of acquiring knowledge. It focuses on what is known to be true and how researchers frame their research in their attempts to discover knowledge. Epistemology has several branches, including positivism, interpretivism, essentialism, historical perspective, perennialism, progressivism, empiricism, idealism, rationalism, and constructivism.

In research, epistemology is closely connected to research methods as they are both concerned with knowledge creation and validation. Researchers philosophical standpoint should be made clear from the beginning, and they should specify research philosophy and research methods that correspond to their chosen epistemology. The choice of an epistemological approach adopted to guide the conduct of research should be justified appropriately.