The number of new confirmed cases of Covid-19 in Singapore has gone up in recent days, with most of them involving foreign workers who stay in dormitories.

While it's true that Singapore is ramping up testing of these workers, and finding more confirmed cases, it does not mean that countries reporting fewer cases are testing fewer people.

Donald Low, former associate dean of the Lee Kuan Yew School of Public Policy, shared a Facebook post on Apr. 17 pointing out this fallacy.

While thankfully, the mortality rate in Singapore from Covid-19 remains relatively low, Low said:

"I also see some people using this argument to say that Taiwan and Hong Kong’s numbers are low because they aren’t testing widely. This is not just denial and defensiveness, it is also factually incorrect."

Easy to get a test in Hong Kong

Low, who is in Hong Kong, said that he could go to a General Practitioner (GP) and ask for a test, or get himself tested at a local public hospital.

Low, who is a Senior Lecturer and Professor of Practice at the Institute of Public Policy of the Hong Kong University of Science & Technology, pointed out there was no way to hide a rising number of Covid-19 by intentionally testing fewer people.

This is due to the fact that if Covid-19 is widespread, hospital admission rates and occupancy of Intensive Care Unit beds would quickly rise, even if the majority of cases are mild or asymptomatic.

As Hong Kong has reported 50 per cent fewer cases of deaths and ICU admissions due to respiratory illness during this flu season as compared to last year, then Hong Kong can't be under-testing the population.

On Apr. 6, the Ministry of Health's Director of Medical Services Kenneth Mak said that the focus was on testing people with symptoms, and not community-based testing, although this was "under review."

On Apr. 4, Mak also mentioned about the active testing of potential Covid-19 cases in dormitories, adding that the testing could lead to a spike in daily reports of unlinked cases.

Cognitive dissonance

Low also pointed out that in his view, the belief that places with lower infection rates must be performing fewer tests reflects a "deep-seated self-superiority and a refusal to acknowledge that in handling this pandemic, others seem to have done a better job than us (so far)."

Low said that such people may already hold negative views of places like Hong Kong and Taiwan, and the possibility that they have done better than Singapore in containing the Covid-19 outbreak could have caused "cognitive dissonance."

When this happens, Low explained how people react to cognitive dissonance:

"And we deal with cognitive dissonance not by adjusting our mental models or world views, but by denial (“there’s something wrong about the data”, “we’re not comparing apples to apples”) and ex post rationalisation (“the number of confirmed cases is not a meaningful statistic”)."

How to recognise if your argument is suffering from outcome bias

Low explained that ex post rationalisation or outcome bias is a common trait in people, but there were ways to recognise if you were making such an error.

Ask yourself:

1. In the early stage of the pandemic, did you already believe that the number of confirmed cases was not a significant statistic, and that countries with more tests and low mortality rates were doing a good job?
2. Did you entertain the possibility that Singapore's low numbers back then might have been the result of inadequate testing? (Even though Singapore was actually testing aggressively from the beginning.)

If you answered yes to both questions, then your argument "does not suffer from outcome bias."

On the other hand, if someone initially held up Singapore's low number of cases as an example of success, and today is saying that the high numbers now are a result of aggressive testing, then their argument may be biased.

You can read the full post here.

Top image from Donald Low's Facebook page and Pixabay.