Death Rate Math
Today a post about the Math of CoViD-19 Death Rate appears on my news feed. Seems like people not interested in working numbers.
A week ago, Elon Musk wrote an email about car crashes and coronavirus. A month ago, someone traveling Vietnam tried to lecture me how to do math with random American Disease Statistics and Chinese CoViD-19 Data. “It is like a flu”. “Death rate is low”. The narrative is nothing to worry, just keep enjoying life as it is. So, I finally decided to list here a few common questions:
How do you calculate death rate? Is it the [ Total of deaths / Total positive cases ] ?
- Wrong if you calculate it by Total Deaths/ Total Confirmed Cases.
- Several ways in different studies. For example:
- It is frequently changed and different from countries.
How do you understand the death rate?
- Math formulation comes up with key assumptions to build models and collect data. For example: the first method comes up with an assumption of 7 days hospitalization on average.
Could you compare it with the death rate of other diseases?
- CoViD-19 is a new disease. We are still collecting data by testing suspicious cases. It is very incompatible to claim any stable numbers and/or compare those with others, especially in seasonal diseases like Influenza or random events like car crashes.
- We lack independent studies to be strongly confident in making a conclusion. It needs time and effort to design experiments, statistical testing, literature review. And this process needed to conduct independently, peer-review and exchange information to form new ideas and hypotheses. And re-iterate this process a couple of times. It takes up to years to refine a statement. There is no magic here. It is a painstaking process with a huge sacrifice.
How do you apply a death rate to learn about your situation?
- Right now it is hard to use science to tell about a situation if you get infected. We lack evidence and time to test hypotheses. The best knowledge comes from certainty about what we know about the healthcare system.
- So let’s forget a story about the death rate of CoViD-19, let’s talk about the death rate in general. Whatever a calculation is, it could not be a comparison. It is a sum of conditional probabilities of all possibilities.
- In other words, It does not matter about CoViD-19, but other diseases as well. Any people with serious health and emergent issues will need to go to hospital.
- That could be your grandmother with a chronic disease, your careless child, your pregnant wife, your husband with heart disease or a young person with lung problems. And regardless of the situation, you will be likely to come to the hospital by using an ambulance for the emergency room or intensive care units. In such a situation, CoViD-19 created surging demand in the healthcare system whereas there is a constraint about beds, ventilators, doctors and nurses. Those are numbers that we should pay attention to. People don’t just die because of CoViD-19, but lack of proper care for their health issues.