A researcher selects 600 adults from England, Scotland, Wales and Northern Ireland. The proportions of different age groups and genders in the sample match those in the UK adult population.

Each participant sits alone in a silent research room facing a blank computer screen. A message tells them to wait for the next task, although no task will appear. Participants can select a button marked “stop waiting” at any time. Beforehand, the researcher tells them, “This study measures how patient you are.” After eight minutes the waiting period ends automatically. Most participants wait for the full eight minutes.

The researcher concludes that “adults living in the UK are patient in everyday life”.

Evaluate the validity of this study.