ABSTRACT
Assessment of the prevalence of the disease or condition should consider the accuracy of the diagnostic tests. In the context of the new coronavirus infection (COVID-19) pandemic, laboratory testing has been one of the most important components of the overall strategy for the control and prevention of this infection. Seroprevalence studies have been used to assess and monitor the level of population immunity to the virus. In this paper we provide detailed description of the methods to calculate and interpret the accuracy of laboratory tests as well as their sensitivity, specificity, positive-and negative prognostic values of laboratory tests using seroprevalence of COVID-19 studies as an example for better understanding of the methodological issues. The use of the laboratory tests accuracy in prevalence studies has been demonstrated. A sample syntax to calculate confidence intervals for the prevalence estimates using the bootstrap procedure with known absolute values of true positive and true negative results, false positive and false negative results for R software is also provided. Presentation of the prevalence estimates adjusted for test performance indicators with confidence intervals improves comparability of the findings obtained using different serological tests. The article is intended for undergraduate-, postgraduate-, and doctoral students in health sciences working with the assessment of the prevalence (seroprevalence) of diseases or conditions through population-based serological surveys. © 2022, Northern State Medical University. All rights reserved.
ABSTRACT
The widespread availability of mobile phones, the development of their functions, and the availability of mobile internet are all con-tributing to the development of new tools for scientific research. Objective. To evaluate the feasibility of using a mobile app to collect health-related data and the impact of this data collection method on the results obtained, using the COVID-19 vaccination attitude assessment as an example. Material and methods. A survey was conducted on attitudes towards COVID-19 vaccination using the «Know Your Heart» mobile app. A total of 1,770 Arkhangelsk region residents aged 35—74 years who participated in the ЭССЕ-РФ3 survey conducted in the Arkhangelsk region in 2021 were invited to install the application and take part in the survey. Multiple logistic regression analysis was used to evaluate factors related to application installation and survey participation. Results. Of the total number of subjects invited to participate in the study, 611 (34.5%) installed the mobile app, and 150 (8.5%) participated in the survey. Subjects under 65 were more likely to install the application than those 65—74, as were subjects with a steady job versus those without one. Subjects under 65 years of age showed a higher responding rate to the invitation to participate in the mobile survey. Individuals who abused alcohol were less likely to agree to participate in the mobile survey. The major-ity of respondents are vaccinated against COVID-19 (81%). Vaccinated subjects and those confident in the effectiveness of non-specific preventive measures were more likely to have positive attitudes towards vaccination. Conclusion. The low response rate to the survey resulting in an unrepresentative sample determined the low effectiveness of the survey using the mobile app. When overcoming these obstacles, mobile applications have the potential to be used in scientific research due to their high speed, accessibility, and ease of data collection.