Study Debunks Reported 2025 Drug Overdose Spike

Research finds the apparent surge was a statistical modeling artifact, not a true reversal in overdose trends.

Apr. 9, 2026 at 7:36am by Ben Kaplan

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A ghostly, translucent X-ray photograph of an opioid pill bottle, its internal structure glowing against a dark background, conceptually representing the clinical, analytical nature of the research debunking the overdose spike.An X-ray analysis of drug overdose data reveals the statistical modeling behind a reported 2025 spike was an artifact, not a true reversal in declining overdose trends.San Francisco Today

A new Northwestern University study has found that a reported surge in U.S. drug overdose deaths in early 2025, which was based on data from the CDC, was not real. The study found overdose deaths have continued to decline following a peak in August 2023, marking the longest sustained decrease in more than four decades. The findings directly address speculation that the CDC made data reporting errors or intentionally mischaracterized or concealed public health data.

Why it matters

Accurate data are essential for public health response. Misinterpreting trends can misdirect policy decisions, undermine public trust and distort resource allocation. Despite this episode, the researchers stress that federal mortality data remain the most reliable near real-time source for tracking overdose death.

The details

The study found the apparent spike was a statistical modeling artifact, not a true reversal in overdose trends. The U.S. relies on provisional mortality estimates from the National Center for Health Statistics, which uses statistical models to account for reporting delays in death investigations. These models performed well for years but struggled when overdose deaths began declining after a prolonged period of rapid growth due to the spread of fentanyl, a synthetic opioid.

  • Overdose deaths peaked in August 2023.
  • The apparent spike in overdose deaths was reported in June 2025.

The players

Lori Ann Post

Lead author of the study and director of the Buehler Center for Health Policy and Economics at Northwestern University Feinberg School of Medicine.

National Center for Health Statistics

The U.S. agency that provides provisional mortality estimates using statistical models to account for reporting delays in death investigations.

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What they’re saying

“Many people think CDC drug overdose data are being cooked, but they're not. We can trust them because they're scientists trying to do the best job they can with difficult circumstances. There was no clear incentive for any administration to inflate these numbers. This was not politics.”

— Lori Ann Post, Director, Buehler Center for Health Policy and Economics, Northwestern University

“What we found was a mismatch between predictive models and a rapidly changing epidemic. CDC scientists did the best job they could with fewer people, more constraints and more people watching them.”

— Lori Ann Post, Director, Buehler Center for Health Policy and Economics, Northwestern University

What’s next

The study authors call for greater transparency in federal data systems, including advance notice of methodological changes and clear documentation of revisions.

The takeaway

This episode highlights the vulnerability of public health surveillance systems during turning points when trends shift direction. Accurate data is essential to guide effective policy responses, and the researchers emphasize the need for continued trust in federal mortality data as the most reliable real-time source for tracking overdose deaths.