Require within‑person causal checks

When longitudinal cohort data include repeated measures, authors should routinely run within‑person (panel) and family fixed‑effects checks before making causal claims; these designs use each person or sibling as their own control and remove many unobserved confounders. High‑profile papers and press releases should report those robustness checks explicitly so policymakers and journalists don't treat conditional between‑person associations as causal. — If adopted as a norm, this would reduce misleading causal claims in science that drive policy and public panic—especially on hot topics like youth social‑media harms.