Diagnostic properties of case definitions of suspected COVID-19 in Chile, 2020/Propiedades diagnosticas de las definiciones de caso sospechoso de COVID-19 en Chile, 2020/Caracteristicas diagnosticas das definicoes de caso suspeito de COVID-19 no Chile, 2020

• Published in: Revista panamericana de salud pública 2021-01, Vol.45
• Main Authors: Aubert, Josefina, Duran, Doris, Monsalves, Maria Jose, Rodriguez, Maria Francisca, Rotarou, Elena S, Gajardo, Jean, Alfaro, Tania, Bertoglia, Maria Paz, Munoz, Sergio, Cuadrado, Cristobal
• Format: Article
• Language: Spanish
• ISSN: 1020-4989
• DOI: 10.26633/RPSP.2021.14

Objective. Compare the diagnostic properties of five case definitions of suspected COVID-19 that were used or proposed in Chile during the first eight months of the pandemic. Methods. An analysis was done of the diagnostic properties (sensitivity, specificity, and positive and negative predictive values) of three case definitions of suspected COVID-19 used in Chile between March and October 2020, as well as two alternative proposed definitions. The sample was 2,019 people with known results for the polymerase chain reaction (PCR) test for SARS-CoV-2. Stepwise logistic regression was used to develop criterion 5, optimizing sensitivity and specificity values. Multifactor logistic regression was used to explore the association between demographic variables, symptoms and signs, and PCR positivity. Different positivity scenarios were analyzed and ROC curves were compared. Results. The presence of anosmia (OR = 8.00; CI95%: 5.34-11.99), fever (OR = 2.15; CI95%: 1.28-3.59), and having been in close contact with a person sick with COVID-19 (OR = 2.89; CI95%: 2.16-3.87) were associated with a positive PCR result. According to the analysis of the ROC curve, criterion 5 had the highest capacity for discrimination, although there were no significant differences with the other four criteria. Conclusions. Criterion 5--based on anosmia, close contact with people with COVID-19, and fever as sufficient unique elements--was the most sensitive in identifying suspected cases of COVID- 19, a key aspect in controlling the spread of the pandemic. Keywords Coronavirus infections; SARS virus; molecular diagnostic techniques; Chile. Objetivo. Comparar las propiedades diagnosticas de cinco definiciones de caso sospechoso de COVID-19 utilizadas o propuestas en Chile durante los primeros ocho meses de la pandemia. Metodos. Se analizaron las propiedades diagnosticas (sensibilidad, especificidad, y valores predictivos positivo y negativo) de tres definiciones de caso sospechoso de COVID-19 utilizadas en Chile entre marzo y octubre del 2020, y dos propuestas de definicion alternativas. La muestra fue de 2 019 personas con resultados conocidos a la prueba de la reaccion en cadena de la polimerasa (PCR) para SARS- CoV-2. Para elaborar el criterio 5 se aplico una regresion logistica escalonada (stepwise) optimizando los valores de sensibilidad y especificidad. Se exploro la asociacion de variables demograficas, sintomas y signos con la positividad a la PCR mediante regresion logistica multi