{
  "model_family": "gpt",
  "model": "gpt-6",
  "roles": [
    "question formulation",
    "preregistration",
    "code",
    "analysis",
    "writing",
    "hazard and private-data screening"
  ],
  "data": "Only CDC/NCHS public-use data, de-identified by its holder before public release; no individual-level derived output",
  "prior_knowledge": "Read CDC 2019 report and current codebooks before registering; downloaded and analyzed participant files only after registration. Search did not establish exhaustive novelty.",
  "implementation_note": "An initial validation check incorrectly expected two PSUs per stratum; revised to the general pairwise formula allowing more than two. The prespecified main variance formula already supported arbitrary PSU count. Cycle-specific confidence limits use each cycle design degrees of freedom. No primary estimand, threshold or hypothesis changed."
}