On April 10th the results of the representative study on COVID-19 prevalence in Austria were published. The aim of the study, in which the Complexity Science Hub Vienna was also involved, was to find out how many people in Austria were infected with corona (prevalence). This is the first study of its kind in the world.

From April 1 until 6 random samples from 1,544 Austrians were taken to find out what the number of unreported cases of coronavirus infections is. The proportion of those positively tested in the weighted sample is 0.33%. This proportion represents about 28,500 people among the population.

Confidence interval (95%)

If a sample survey draws a conclusion on a population, the confidence interval must always be observed. For this study, the generally accepted principle was applied that results should be within the stated interval with 95% certainty.

Applying the Clopper-Pearson interval method, we find that the prevalence of COVID-19 in Austrian households is 95% likely to be between 0.12 and 0.76%.

In absolute terms: In addition to the patients in hospitals, there were between 10,200 and 67,400 people acutely infected with COVID-19 in the period April 1- 6.

Net sample n=1,544

• For n = 1,541 persons, both a correct PCR test and a valid questionnaire are available.
• During recruiting, n = 3 people indicated that they had recently tested positive. These were not tested again but included in the sample as having tested positive. This allows the sample to be corrected for systematic error.
• The net sample used for the calculations therefore contains n = 1,544 cases.

For more information please check https://www.sora.at/nc/news-presse/news/news-einzelansicht/news/covid-19-praevalenz-1006.html