A scientist might say, "There is evidence of causation." Typically in scientific research, to assert causation three things must be true: 1) Correlation, 2) Te

A scientist might say, "There is evidence of causation." Typically in scientific research, to assert causation three things must be true: 1) Correlation, 2) Temporal ordering (for A to cause B, A must come before B), and 3) Sufficient theorizing, in other words, a plausible explanation, typically based on previously accepted research. In the best settings, random samples from a population with a treatment condition and a control condition are the best evidence. That's not possible in an age-base study, as randomly selected groups are not treatable with "age", and even if it were somehow possible, it probably wouldn't be ethical to do so. Unfortunately, some of the most important research can't be done with this sort of A/B test. Consequently, assertions of causation are sometimes incorrect. But that's true with any research methodology. Know that the question of causation is something the scientific community wrestles with, and a moderately informed population shouting "correlation != causation", while typically a good response to a newspaper article, isn't always the most helpful with regard to a scientific journal.