Nick if you could get past your jingoistic xenophobia and actually looked at the research you would find it was done by a prestigious University:
Institute of Social and Preventive Medicine
University of Bern
Bern, Switzerland
Clearly there is the possibility and potential for "less than factual" data reporting, however this is a well respected academic institute, their reputation is at stake.
The data was extracted from the CCDC report . We assumed that all deaths were reported and that
all symptomatic cases among people of aged 80 years and older were also reported. For the other age classes, we modelled the underreporting of symptomatic cases by an age-dependent reporting rate. We used negative binomial distributions to describe the number of reported cases and deaths and multinomial distributions to describe the distribution of cases and deaths over age classes. We implemented the model in a Bayesian framework using Stan[15]. All code and data are available from
https://github.com/jriou/covid_adjusted_cfr.