A health-study average comes from the people who were actually studied. Its title may name a broad condition while the eligibility criteria describe a much narrower group.
Find the boundaries of participation
The NIH Clinical Center’s introduction to research participation explains inclusion and exclusion criteria. These can concern characteristics such as age, health conditions or treatment history. Read the criteria alongside the reported participants, because eligibility and eventual enrolment are related but different descriptions.
For an invented example, a study might include adults within a specified age range and exclude a particular coexisting condition. A headline that says “works for adults” would leave out those boundaries. The exclusion does not prove the intervention is ineffective or unsafe for everyone outside the study; it means this particular study may not directly answer their question.
Write a narrower, more useful summary
Record who was eligible, who took part, the setting and the follow-up period. Then state the result using that population rather than silently expanding it. If the source does not report a detail, mark it as unavailable instead of filling it from expectations.
Eligibility rules can serve safety and methodological purposes, but overly restrictive recruitment may also limit applicability. Reading them is therefore part of understanding evidence, not a shortcut to judging whether a trial is good or bad. Individual care decisions need a clinician’s assessment of the wider evidence and the person’s circumstances.
AI-generated editorial illustration; not a documentary photograph.