Pharmacist direct-authority naloxone laws do not show preregistered attenuation under fentanyl dominance on WONDER age-adjusted rates

Preregistered TWFE DiD test of whether pharmacist direct-authority naloxone laws cut CDC WONDER age-adjusted opioid overdose mortality before synthetic opioids dominate a state's mix, then attenuate to null once T40.4 accounts for at least half of opioid overdose deaths. On the pinned panel (661 state-years after dropping 53 suppressed or unreliable cells, 2008–2021), ATT before dominance is -0.285902 (CI -3.772196 to 3.200392); the Law×SyntheticDominant interaction is -0.926561; ATT when dominant is -1.212463. Locked success flag false is false (decision ). Re-run from .