I’ve seen several posts on Facebook claiming that deaths of relatives or friends have been falsely attributed to covid-19 when in fact they were due to some other cause. These anecdotes represent a misunderstanding of the way statistics work and how data for statistics is collected. Of course, researchers want as accurate a count as possible for the number of deaths caused by Covid-19. But that kind of accuracy is harder than it sounds.
At first researchers were counting only deaths where the person who died had tested positive for Covid-19. They soon realized however, that they were under-counting the number of Covid-19 deaths. How did they realize that? They knew what the death rate in a particular place was prior to the pandemic. For example, if a city typically had 1,000 deaths in 30 days, and suddenly the number jumps to 3,000 but only 1,500 of those were due to patients who tested positive for Covid-19, then that left 500 deaths unaccounted for. So researchers decided to broaden the criteria for recording deaths as attributable to Covid-19. They decided to included deaths where symptoms were similar to those caused by Covid-19. They also included deaths even when the patient tested negative.
Why would someone who tested negative for covid-19 still be listed as a victim of it? Testing is not 100% accurate. Data on accuracy of the most widely used Covid-19 test is not publicly available, but some estimates range as high as 30% for false negatives, meaning that 3 out of 10 people who test negative for the disease actually have it. Even with a test that is 100% accurate under ideal conditions, real-world conditions can skew results. Many conditions can affect the amount of virus in a specimen collected by a swab. The most widely used test has close to a 100% accuracy for positive results, the the accuracy for negative results is uncertain and can vary depending on many factors. This is why some people who have died after testing negative for covid-19 are nevertheless listed as victims of covid-19. As long as they had symptoms consistent with the infection, they might very well have covid-19 listed on their death certificate. Of course, casting a broader net for data also means that there will be instances of people being listed as having died from covid-19 who actually died of other causes. Researchers make every effort to ensure this does not happen, but no procedure is foolproof. However, if the number of deaths identified as having been caused by Covid-19 matches the uptick in deaths overall, then it’s a pretty safe assumption that the data is pretty clean.
Because many people are suspicious of our government or the media or liberal elites—none of which are actually sufficiently monolithic to carry off a genuine conspiracy—and of expert authority in general, these types of stories gain currency on social media. Some may be true, but they usually do not contain sufficient detail to validate them. Even if they are true, they are generally offered by people who are not experts in determining cause of death.
So before you share one of these anecdotes about a suspicious Covid-19 death, consider not just whether it is true, but also whether it undermines the very institutions we have put in place to help us deal with infectious disease epidemics. While there are plenty of politicians ready to make hay out of crisis events, the experts and researchers who do the actual work genuinely care about producing good quality studies that advance our understanding of the virus and how it spreads. They are not out to get you.