Concordance between self-reported SARS-CoV-2 positivity and laboratory-confirmed positivity

Area of Science:

• Epidemiology
• Public Health Surveillance
• Infectious Disease Research

Background:

• Increased use of at-home SARS-CoV-2 antigen tests has led to decreased reporting to state surveillance systems.
• Accurate self-reported infection dates are crucial for tracking COVID-19 incidence, outbreaks, and illness progression.
• The reliability of self-reported SARS-CoV-2 test dates has not been previously established.

Purpose of the Study:

• To assess the accuracy of self-reported SARS-CoV-2 test dates compared to laboratory-confirmed dates.
• To identify participant characteristics associated with inaccurate self-reporting of test dates.

Main Methods:

• Utilized self-reported testing data from the Arizona CoVHORT Study and laboratory-confirmed data from the Arizona Department of Health Services.
• Calculated the difference in days between self-reported and laboratory-confirmed test dates.
• Employed logistic regression to analyze factors associated with reporting a test date >7 days different from the confirmed date.

Main Results:

• 82.5% of participants reported a test date within 7 days of the laboratory-confirmed date.
• Increasing age (≥55 years) and longer time between positive test and self-report were associated with greater discrepancies.
• Participants aged 55+ had an 84% increased likelihood of inaccurate reporting; each week delay increased inaccuracy by 2%.

Conclusions:

• Self-reported SARS-CoV-2 test dates demonstrate 82% agreement with laboratory-confirmed dates, suggesting sufficiency for Long COVID/Post-COVID Conditions surveillance when lab data is unavailable.
• Accuracy decreases with increasing age and longer delays in self-reporting.
• Public health initiatives should consider these factors when utilizing self-reported data for surveillance.