key: cord-0926710-jj0dy2l8 authors: Ahmed, A. title: Does COVID-19 Testing Create More Cases? An Empirical Evidence on the Importance of Mass Testing During a Pandemic date: 2020-12-26 journal: nan DOI: 10.1101/2020.12.23.20248740 sha: c42a755e66b649a060e6f6500622d14ea510c6a3 doc_id: 926710 cord_uid: jj0dy2l8 The importance of testing and surveillance of an infectious disease cannot be underestimated. The testing is the first step to detect an infectious disease, and mass testing can slow or mitigate the spread of an infectious disease. Despite overwhelming evidence and the importance of testing discussed in the literature, there have been claims that "more COVID-19 testing creates more cases". Therefore, there is a need to study whether massive testing is the reason for detecting more positive COVID-19 cases. In this research, we used a dataset from the U.S. Department of Health & Human Services and empirically showed that by increasing the COVID-19 testing in the U.S., the spread of the COVID-19 decreased significantly. Our results indicate a negative relationship between the number of positive cases and the number of tests performed in the past months. The large-scale testing may have helped identify positive and asymptomatic cases early in the course of illness, which enabled individuals to isolate themselves, thus reducing the chances of spreading the diseases and slowing the spread of the pandemic. Detection and surveillance of an infectious disease is the first step in controlling a pandemic 1 . However, not much attention has been given to understand the role of testing in mitigating an infectious disease's spread 2 . In this research, we present empirical evidence of how testing effects the spread of the disease and the number of positive cases in the future. We propose increasing the COVID-19 testing capacity in a given population may help identify asymptomatic and early cases, resulting in deterrence and decreased positive cases in the future. Specifically, we have analyzed a relationship between the number of positive cases reported in a month and the number of tests performed in the past months. We used a publicly available dataset released by the U.S. Department of Health & Human . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the idiosyncratic error of the models. Our results suggest a negative relationship between the number of positive cases and the number of tests performed in the past months. In Table 1 , Column 1 and 2 shows the estimated models is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 26, 2020. ; https://doi.org/10.1101/2020.12.23.20248740 doi: medRxiv preprint the number of tests performed in all the previous months (i.e. , −1 ). The overall relationship suggests that having more tests in previous months reduces the number of positive cases in the coming months. Figure 1 shows the predicted relationship for both the models. Our research explains the relationship between COVID-19 testing and positive cases. We provide empirical evidence on the importance of mass testing and its effects on controlling the . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint The copyright holder for this this version posted December 26, 2020. ; https://doi.org/10.1101/2020.12.23.20248740 doi: medRxiv preprint pandemic. These analyses also refute the misperception that more tests yield more positive cases. We have shown that increasing the number of the tests yield fewer cases in the future-testing and surveillance help identify asymptomatic cases, which create deterrence and decrease the disease's spread 2 . In short, mass testing mitigates the spread and yields less positive cases in the coming months. . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint The copyright holder for this this version posted December 26, 2020. ; https://doi.org/10.1101/2020.12.23.20248740 doi: medRxiv preprint The Need for More and Better Testing for COVID-19 Rapid Antibody-Based COVID-19 Mass Surveillance: Relevance, Challenges, and Prospects in a Pandemic and Post-Pandemic World Department of Health & Human Services. COVID-19 Diagnostic Laboratory Testing (PCR Testing) Time Series