Certified Tester Foundation Level (CTFL v4.0) — Chapter 4: Test Analysis and Design

Chapter 4 is the largest chapter of the exam and the only one that asks you to produce an answer rather than recognise one. It covers black-box techniques (equivalence partitioning, boundary value analysis, decision tables, state transition testing), white-box techniques (statement and branch coverage), experience-based techniques (error guessing, exploratory testing, checklist-based testing) and collaboration-based approaches (user stories, acceptance criteria, acceptance test-driven development).

Eleven of forty points, and five of the exam's eight K3 questions live here. Reading about these techniques is not preparation — you have to derive partitions, count test cases and trace transitions until you can do it in under a minute.

Where candidates lose these points:

• 2-value vs 3-value boundary value analysis — 2-value takes each boundary and its nearest neighbour; 3-value adds the value on the other side. For one boundary that is 2 values versus 3, and the question always states which variant it wants.

• Minimum test cases for equivalence partitioning — the answer is the largest number of partitions in any one parameter, not the sum and not the product, because partitions of different parameters can be combined in one test.

• Statement vs branch coverage — 100% branch coverage implies 100% statement coverage, never the reverse. An if with no else still has two branches.

• 0-switch coverage — one test per valid transition, counted from the diagram. The initial arrow into the start state is not a transition to test, and invalid transitions are not counted.

• Collapsing decision table rules — rules merge only when they share the same action and the differing conditions genuinely do not matter.