Citation: Preskorn SH. COVID-19: Why Has the Mortality Rate Declined? J Psychiatr Pract. 2020 Sep;26(5):394-399. doi: 10.1097/PRA.0000000000000494. PMID: 32865940. https://pubmed.ncbi.nlm.nih.gov/32865940/ and https://journals.lww.com/practicalpsychiatry/Abstract/2020/09000/COVID_19__Why_Has_the_Mortality_Rate_Declined_.6.aspx (only abstract available, not details.)
One key factor that was not known in the earliest days of the pandemic was that many patients are either asymptomatic or have symptoms so mild that they may not seek medical attention and hence these patients would not be identified as a “case” if that term is defined as being sufficiently symptomatic to be seeking medical attention. Cases in the earliest days of the pandemic were defined as based on having symptoms (eg, fever, cough, respiratory distress) after ruling out other possible causes.
I.e. Early on in the pandemic, doctors used their discretion, not a standardized procedure, nor a lab test, to rule out other cases and decide whether the person had COVID-19 or not.
