Diagnostic performance of RT-PCR-based sample pooling strategy for the detection of SARS-CoV-2.

BACKGROUND: The rapid spread of SARS-CoV-2 has created a shortage of supplies of reagents for its detection throughout the world, especially in Latin America. The pooling of samples consists of combining individual patient samples in a block and analyzing the group as a particular sample. This strategy has been shown to reduce the burden of laboratory material and logistical resources by up to 80%. Therefore, we aimed to evaluate the diagnostic performance of the pool of samples analyzed by RT-PCR to detect SARS-CoV-2. METHODS: A cross-sectional study of diagnostic tests was carried out. We individually evaluated 420 samples, and 42 clusters were formed, each one with ten samples. These clusters could contain 0, 1 or 2 positive samples to simulate a positivity of 0, 10 and 20%, respectively. RT-PCR analyzed the groups for the detection of SARS-CoV-2. The area under the ROC curve (AUC), the Youden index, the global and subgroup sensitivity and specificity were calculated according to their Ct values that were classified as high (H: ≤ 25), moderate (M: 26-30) and low (L: 31-35) concentration of viral RNA. RESULTS: From a total of 42 pools, 41 (97.6%) obtained the same result as the samples they contained (positive or negative). The AUC for pooling, Youden index, sensitivity, and specificity were 0.98 (95% CI, 0.95-1); 0.97 (95% CI, 0.90-1.03); 96.67% (95% CI; 88.58-100%) and 100% (95% CI; 95.83-100%) respectively. In the stratified analysis of the pools containing samples with Ct ≤ 25, the sensitivity was 100% (95% CI; 90-100%), while with the pools containing samples with Ct ≥ 31, the sensitivity was 80% (95% CI, 34.94-100%). Finally, a higher median was observed in the Ct of the clusters, with respect to the individual samples (p < 0.001). CONCLUSIONS: The strategy of pooling nasopharyngeal swab samples for analysis by SARS-CoV-2 RT-PCR showed high diagnostic performance.

Prevalencia, características y factores asociados del Síndrome de Burnout o agotamiento estudiantil en los alumnos de la Escuela de Medicina Humana de la Universidad Privada de Tacna en el año 2006 / Prevalence, characteristics and factors associated Burnout Syndrome or student burnout in students of the College of Human Medicine, Private University of Tacna in 2006

El presente trabajo de investigación, comprende el estudio de la prevalencia, caracteristicas y factores asociados del Síndrome de Burnout o Agotamiento Estudiantil en los alumnos de la Escuela de Medicina Humana de la Facultad de Medicina de la Universidad Privada de Tacna en el año 2006-II. Es un estudio observacional, prospectivo, transversal y correlacional. Se utilizó el Cuestionario de Maslach Burnout Inventory (MBI), en su versión española. Se encuestaron 201 alumnos pertenecientes al II, IV, VI, VIII y X ciclo académico. Para el análisis descriptivo se utilizó los paquetes SPSS-PC, W5.0 y Epiinfo 6.0; y para el estadístico, pruebas de regresión logística y riesgo con cálculo de OR e intervalos de riesgo con un valor p aceptable menor a 0.05. La prevalencia obtenida para el Síndrome de Burnout o Agotamiento estudiantil fue del 17.9%, presentándose con mayor frecuencia en el sexo masculino, entre 20 a 25 años, solteros, que estudian 1 a 2 horas diarias fuera de la carga académica correspondiente a cada ciclo, que han rendido por lo menos una vez examen de aplazados y que han desaprobado por lo menos un curso. Los factores asociados estadisticamente significativos más frecuentes son: distribución de la carga lectiva a lo largo de la carrera, falta de concordancia entre la amplitud de los temarios y los créditos reconocidos, preocupación por conducta incorrecta de familiares, problemas relacionados con la vida sexual y dependencia económica.