A deductive, or "top-down," approach to research methodology begins with hypotheses based on existing knowledge or literature. In other words, it seeks to test an established theory.
Inductive, or "bottom-up," research, by comparison, collects data and observations in order to discern a pattern within them, or to formulate a new theory.
The procedure followed by deductive research can be summarized as follows:
- Theory, starting with existing knowledge or assumptions.
- Hypothesis, formulating a research question or hypothesis based on existing knowledge, theories or assumptions.
- Observation, or data collection.
- Confirmation, conclusions drawn on the basis of the observations or data collected, ultimately leading to either confirmation or rejection of the initial theory.