Instruct: Identify the main category of Medrxiv papers based on the titles and abstracts
Query: A Scaling Law for PCR Positivity in the COVID Second Wave In this preliminary report, PCR positivity data in the second wave of the COVID pandemic (September-January 2020) are shown to obey a scaling law given by: O_FD O_INLINEFIG[Formula 1]C_INLINEFIGM_FD(1)C_FD where % P0 and {Sigma}0 are the y- and x-intercepts of a plot of positivity, %P, against the number of tests, {Sigma}. The law holds across international, regional and local boundaries, as demonstrated for Great Britain, Austria, Germany and Sweden, the nine English regions, London - Yorkshire & Humber, and various Local Health Authorities in England. One possible explanation for scaling might be Dorfman pooling.

The scaling law can be used to remove a systematic or false positive (FP) component from the daily number of positive tests, or cases, to yield the real number of cases. The results correlate strongly with the ZOE survey for London (R2=0.787) and Excess Deaths for England (R2=0.833). The cumulative total of FPs can be estimated as 1.4M by the beginning of 2021, in line with other estimates.
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The categories of this paper are: informatics
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The categories of this paper are: oncology
53
The categories of this paper are: pathology
2
The categories of this paper are: medicine
47
The categories of this paper are: care
73
The categories of this paper are: toxicology
57
The categories of this paper are: primary
12
The categories of this paper are: genomic
42
The categories of this paper are: occupational
32
The categories of this paper are: rehabilitation
60
The categories of this paper are: addiction
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The categories of this paper are: reproductive
48
The categories of this paper are: critical
62
The categories of this paper are: orthopedics
13
The categories of this paper are: genetic
67
The categories of this paper are: transplantation