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By Dr. Ali Murfi, M.Sc.
A research gap identifies what remains missing, unresolved, or insufficiently understood in existing research. Building on earlier frameworks, Miles (2017) proposes seven types to help researchers clarify the need for further investigation.
1. Evidence Gap
Previous studies produce conflicting findings that require clarification.
2. Knowledge Gap
Existing research does not provide the knowledge needed to understand a particular issue.
3. Practical-Knowledge Gap
Professional practices differ from research findings or recommended practices, or remain insufficiently addressed by research.
4. Methodological Gap
Different methods or research designs are needed to generate new insights or address potential distortions in earlier findings.
5. Empirical Gap
Existing findings or propositions require further evaluation or verification through empirical research.
6. Theoretical Gap
Theoretical explanations are insufficient, conflicting, or inadequately applied to the issue being studied.
7. Population Gap
Particular populations or subgroups are underrepresented or insufficiently studied in previous research.
These gaps can overlap, but they are not interchangeable. For example, missing knowledge may also reflect a lack of empirical verification. Identifying the specific gap helps explain both what your study addresses and why it matters.
Source: Adapted from Miles (2017, pp. 3–5), A Taxonomy of Research Gaps: Identifying and Defining the Seven Research Gaps.