A [hypothetical] new drug was created and evaluated in a large international, rigorously designed randomised controlled trial (RCT) to determine its ability to lower blood pressure in people with risk factors for cardiovascular disease. The study showed very promising results. When administered in routine clinical practice, however, blood pressure improvements were not observed. Further examination led to a hypothesis that the new drug did not perform well in the more generalist population due to their many differing chronic disease comorbidities (and likely associated drug interactions) compared to the participants in the RCT (people with comorbidities were not eligible for recruitment).

True or false: This observation is a good example of an intervention proving to have good effectiveness but poor efficacy.