New study finds that widespread underreporting of Covid-19 deaths cannot be explained simply by differences in countries’ ability to count and record deaths. Across 134 countries and territories, an estimated 45%–55% of governments misreported Covid mortality, with underreporting far more common than overreporting. The study provides comparable country-level data of the extent of misinformation for researchers and policymakers. The findings point to a broader lesson beyond the pandemic: strong institutions and an informed public can play an important role in protecting the reliability of official information.
During the Covid-19 pandemic, governments around the world faced the same basic challenge: measuring a fast-moving public-health crisis and communicating its severity to citizens.
But did official data reflect what was actually happening?
A new study by Ariel Karlinsky (Hebrew University) and Prof. Moses Shayo (Hebrew University & King’s College London) , suggests that in many countries they did not. Published in the Journal of Economic Growth , the research compares officially reported Covid deaths with estimates based largely on excess mortality, deaths above the number that would normally have been expected.
Using Covid as a Global Test Case
Karlinsky and Shayo assembled mortality data from 134 countries and territories , drawing on national statistical offices, population registries, health ministries and other sources.
Across the countries studied, governments reported 5.08 million Covid deaths in 2020 and 2021 , while the researchers estimate actual Covid mortality at 12.47 million . Their analysis indicates that roughly 45%–55% of governments misreported Covid mortality , with underreporting far more common than overreporting.
Importantly, the researchers do not assume that every reporting gap represents deliberate manipulation. Countries differ in their ability to diagnose illness, register deaths and maintain reliable statistical systems. The study therefore examines whether differences in state capacity can explain the discrepancies.
Capacity explains only a small share of the variation.
Why Institutions Matter
A stronger relationship emerges when the researchers examine the constraints governments face.
Countries with stronger institutional checks and balances show much less underreporting. Misreporting is also lower where citizens are better positioned to evaluate official information, measured through factors including education and internet access.
The authors also find higher levels of misreporting in countries holding elections during the pandemic and in countries with a communist legacy, although they emphasize that these relationships are descriptive and do not establish causation.
The broader finding is that incentives to present information favorably may exist in many political systems. What appears to matter is whether governments face effective institutional and social checks that make inaccurate information easier to detect and challenge.
Why This Matters Beyond Covid
Covid offered researchers an unusual opportunity: governments around the world confronted a broadly comparable crisis at roughly the same time.
But the implications extend beyond public health.
Governments routinely produce statistics that influence decisions about economic growth, unemployment, public health, international aid and other major policy issues. During Covid, reported figures also influenced international decisions, including travel restrictions.
The study argues that inaccurate official information can therefore have consequences far beyond the country producing it, complicating international efforts in areas such as foreign aid, climate action and vaccination campaigns .
This question has become even more relevant in today's fast-moving information environment, where misleading claims can spread rapidly through digital platforms and AI-generated content.
Looking Beyond the Headline Number
One of the study's key contributions is its use of excess mortality as an independent benchmark.
Official Covid deaths depended on identifying Covid as a specific cause of death, which could be affected by testing and reporting practices. Excess mortality instead asks a simpler question: How many people died compared with how many would normally have been expected?
Comparing the two allowed the researchers to identify reporting gaps that could not easily be explained by differences in countries' statistical capacity alone.
The principle extends beyond Covid: important official claims become more reliable when they can be tested against independent evidence.
Trust Depends on Verification
The findings do not suggest that official statistics should automatically be distrusted. Rather, they demonstrate why systems capable of independently verifying, challenging and correcting information matter.
Karlinsky and Shayo find that governments facing stronger institutional and social constraints generally report more accurately, while those facing fewer constraints show larger discrepancies.
Covid therefore provides more than a case study in pandemic mortality. It offers a window into a much broader question: What makes official information trustworthy?
The research suggests that part of the answer lies not only in governments' ability to produce good data, but also in the strength of the institutions and societies capable of holding those governments to account.
Journal of Economic Growth
Data/statistical analysis
Not applicable
Manipulation of information in times of crisis: Evidence from Covid excess mortality
25-Apr-2026