Categories of Test Design Techniques

What are Test Design Techniques?

Test design techniques are systematic methods used to derive and select test cases, ensuring good coverage with a manageable number of tests.

The Three Main Categories

• Specification-Based (Black Box) Techniques: Derive tests from requirements or specifications without looking at the internal code (e.g., BVA, ECP, decision tables, state transition testing).
• Structure-Based (White Box) Techniques: Derive tests based on the internal structure of the code (e.g., statement coverage, branch coverage, path coverage).
• Experience-Based Techniques: Derive tests based on the tester's knowledge, intuition, and experience with similar applications (e.g., error guessing, exploratory testing).

Why Categorisation Matters

Combining techniques from different categories gives more comprehensive coverage — specification-based techniques ensure functional correctness, structure-based techniques ensure code coverage, and experience-based techniques catch issues that formal techniques might miss.