John Sweller and colleagues run three experiments intended to explore the hypothesis that the Testing effect may not hold for high Element interactivity tasks; students who study more worked examples may prevail (i.e. a Worked example effect).
In their first two experiments, they find an inverted testing effect, but students are tested immediately (The testing effect may be diminished or inverted for immediate tests). In experiment 3, the retention interval is extended to one week, and they find a slightly positive testing effect (not stat sig, though Rawson argues (see van Gog, T., & Sweller, J. (2015). Not New, but Nearly Forgotten: The Testing Effect Decreases or even Disappears as the Complexity of Learning Materials Increases. Educational Psychology Review, 27(2), 247–264) that it would be significant if they’d used a one-sided test, which would be justified given the prior literature).