ABA Exam CoachLessons · D. Experimental Design
D.2 · Internal vs. external validity
Your intervention worked, so you're done, right? Not quite. There are two separate questions to ask: did your intervention really cause the change, and will it work anywhere else? Let's sort them out.
Key takeaway
Internal validity asks whether the intervention caused the change in behavior and not some confound, like an outside event or maturation. Strong experimental control shows a functional relation. External validity, also called generality, asks whether that functional relation holds for other people, settings, behaviors, and times. In ABA, generality comes from direct and systematic replication, not from large group samples.
Internal validity asks whether the intervention caused the change in behavior and not some confound, like an outside event or maturation. Strong experimental control shows a functional relation. External validity, also called generality, asks whether that functional relation holds for other people, settings, behaviors, and times. In ABA, generality comes from direct and systematic replication, not from large group samples.
Members get the full lesson video, notes and a 5-question test
The video walks through the idea, worked examples, the trap people fall into and an exam-style question. The notes and the checkpoint come with it, and your results feed your Where to focus plan.