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Variability in Long COVID Definitions and Validation of Published Prevalence Rates
Lauren E Wisk1, Michelle L'Hommedieu1, Kate Diaz Roldan1
1Division of General Internal Medicine and Health Services Research, David Geffen School of Medicine at the University of California, Los Angeles.
Prevalence of long COVID varied significantly based on different definitions used in a large US cohort study. This highlights the urgent need for a standardized definition for accurate diagnosis and research.
Area of Science:
- Epidemiology
- Infectious Diseases
- Public Health
Background:
- Long COVID definitions lack consensus, complicating accurate prevalence measurement and research efforts.
- Clinical care and research are hindered by the wide variation in how long COVID is defined.
Purpose of the Study:
- To assess the prevalence of long COVID using multiple definitions from published literature.
- To evaluate the sensitivity and specificity of existing long COVID definitions against self-reported cases.
Main Methods:
- Prospective, multicenter cohort study (INSPIRE registry) of 4575 participants aged 18+ with SARS-CoV-2 infection.
- Utilized various published long COVID definitions to calculate prevalence at 3 and 6 months post-infection.
- Compared published definitions against self-reported long COVID for sensitivity and specificity analysis.
Main Results:
- Long COVID prevalence varied widely, ranging from 30.84% to 42.01% at 3 months and 14.23% to 21.94% at 6 months post-infection.
- Published definitions showed low-to-moderate sensitivity (up to 66.32% at 3 months) but high specificity (up to 94.26% at 6 months) compared to self-reporting.
- Significant discrepancies in prevalence estimates were observed across different definitions and time points.
Conclusions:
- The wide variability in long COVID prevalence underscores the critical need for a standardized, validated definition.
- A standardized definition is essential for improving clinical recognition, research comparability, and guiding accurate diagnosis and treatment.
- Further research is required to establish a universally accepted definition for long COVID.
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