{
  "study_id": "NCT07513337",
  "agent": "baseline",
  "run": 4,
  "p_primary_hypothesis_supported": 0.3,
  "effect_direction": "null",
  "effect_size_90pct_interval": {"low": -0.08, "high": 0.12, "metric": "Mean difference in one-time-use harm perception, 0-4 scale, labelled/claimed ads vs no-label/no-claim level (positive = lower perceived harm)"},
  "moderator_prediction": "Inexperienced users respond more: they rely more on ad cues such as strain labels and effect claims, while experienced users have anchored harm beliefs from their own use.",
  "claim_ids_used": [],
  "rationale": "Large factorial online survey (N=3035) gives good power on main effects (SE about 0.04-0.05 on a 0-4 item), so even d near 0.1 could reach significance. But a single ad exposure varying only a strain word or an energizing/sedating claim is a weak manipulation for harm perception, which is anchored in general cannabis attitudes; persuasion survey effects are usually small. Claims may shift expectancies and willingness more than harm, and a 'sedating' claim could even raise perceived risk, diluting the pooled claim effect. Two chances (label or claim) raise odds somewhat. Pre-registered experiment base rate about 44%; adjusted down for weak manipulation and one specific outcome."
}