Validación de test de flexión-relajación para definir un déficit lumbar con electrodos tetrapolares / Validation of the flexion-relaxation test to define a lumbar deficit with tetrapolar electrodes

Introducción y objetivo: Obtener un nuevo punto de corte (PC) para un test de flexión-relajación (FR) lumbar efectuado con electrodos (e.) tetrapolares, desde valores ya definidos con dispositivos bipolares.Materiales y métodosLa muestra del estudio consta de 47 pacientes en situación de incapacidad temporal por dolor lumbar (DL). Fueron evaluados mediante un test de dinamometría isométrica, una prueba cinemática y una valoración del fenómeno FR.Se plantean dos experimentos con curvas ROC. El primero, con 47 pacientes que efectuaron de modo consecutivo el test FR con ambos tipos de electrodos, utilizándose como variable de clasificación el punto de corte conocido para los e. bipolares (2,49uV). En el segundo, con los datos de la EMGs registrados con e. tetrapolares en 17 pacientes, se efectúa un test de DeLong que compara las 2 curvas ROC que construimos, por un lado, al clasificar la muestra desde pruebas de dinamometría y cinemática, y por el otro, al clasificarlos con los valores de la EMGs bipolar.ResultadosUn total de 34 pacientes completaron adecuadamente las valoraciones del primer experimento y 17 pacientes el segundo. El primer estudio arroja un punto de corte de 1,2uV, con un AUC del 87,7%; sensibilidad 84,2% y especificidad 80%. El segundo muestra un PC para los e. bipolares de 1,21uV (AUC 87,5%) y para los e. tetrapolares de 1,43 (AUC 82,5%) con un test de DeLong sin diferencias significativas entre ambas curvas (p>0,4065).ConclusionesLa metodología de validación con curvas ROC ha permitido obtener un nuevo PC para la prueba FR de modo práctico, simplemente simultaneando ambos test sobre el mismo grupo de pacientes hasta obtener una muestra significativa. (AU)

Introduction and objective: To obtain a new cut-off point (CP) for a lumbar flexion-relaxation (RF) test established with tetrapolar (e.) electrodes, from values already defined with bipolar devices.Materials and methodsThe study sample consists of 47 patients in a situation of temporary disability due to low back pain (DL). They were evaluated by means of an isometric dynamometry test, a kinematic test and an assessment of the FR phenomenon.Two experiments with ROC curves are proposed. The first, with 47 patients who consecutively performed the RF test with both types of electrodes, using the cut-off point (CP) known for the e. bipolar (2.49μV). In the second, with the EMG data recorded with e. tetrapolar in 17 patients, a DeLong test was performed that compares the 2 ROC curves that were constructed on the one hand, by classifying the sample from dynamometry and kinematic tests, and on the other, by classifying them with the bipolar EMG values.ResultsA total of 34 patients adequately completed the evaluations of the first experiment and 17 patients the second. The first study shows a cut-off point of 1.2μV, with an AUC of 87.7%; Sensitivity 84.2% and Specificity 80%. The second shows a PC for e. bipolars of 1.21μV (AUC 87.5%) and for e. tetrapolar values of 1.43 (AUC 82.5%) with a DeLong test without significant differences between both curves (p>0.4065).ConclusionsThe validation methodology with ROC curves has made it possible to obtain a new PC for the RF test in a practical way, simply by simultaneously performing both tests on the same group of patients until a significant sample is obtained. (AU)

[Validation of the flexion-relaxation test to define a lumbar deficit with tetrapolar electrodes]. / Validación de test de flexión-relajación para definir un déficit lumbar con electrodos tetrapolares.

INTRODUCTION AND OBJECTIVE: To obtain a new cut-off point (CP) for a lumbar flexion-relaxation (RF) test established with tetrapolar (e.) electrodes, from values already defined with bipolar devices. MATERIALS AND METHODS: The study sample consists of 47 patients in a situation of temporary disability due to low back pain (DL). They were evaluated by means of an isometric dynamometry test, a kinematic test and an assessment of the FR phenomenon. Two experiments with ROC curves are proposed. The first, with 47 patients who consecutively performed the RF test with both types of electrodes, using the cut-off point (CP) known for the e. bipolar (2.49µV). In the second, with the EMG data recorded with e. tetrapolar in 17 patients, a DeLong test was performed that compares the 2 ROC curves that were constructed on the one hand, by classifying the sample from dynamometry and kinematic tests, and on the other, by classifying them with the bipolar EMG values. RESULTS: A total of 34 patients adequately completed the evaluations of the first experiment and 17 patients the second. The first study shows a cut-off point of 1.2µV, with an AUC of 87.7%; Sensitivity 84.2% and Specificity 80%. The second shows a PC for e. bipolars of 1.21µV (AUC 87.5%) and for e. tetrapolar values of 1.43 (AUC 82.5%) with a DeLong test without significant differences between both curves (p>0.4065). CONCLUSIONS: The validation methodology with ROC curves has made it possible to obtain a new PC for the RF test in a practical way, simply by simultaneously performing both tests on the same group of patients until a significant sample is obtained.

[ROC curves: general characteristics and their usefulness in clinical practice]. / Curvas ROC: características generales y su uso en la práctica clínica.

The use of diagnostic tests to determine the presence or absence of a disease is essential in clinical practice. The results of a diagnostic test may correspond to numerical estimates that require quantitative reference parameters to be transferred to a dichotomous interpretation as normal or abnormal and thus implement actions for the care of a condition or disease. For example, in the diagnosis of anemia it is necessary to define a cut-off point for the hemoglobin variable and create two categories that distinguish the presence or absence of anemia. The method used for this process is the preparation of diagnostic performance curves, better known by their acronym in English as ROC (Receiver Operating Characteristic). The ROC curve is also useful as a prognostic marker, since it allows defining the cut-off point of a quantitative variable that is associated with greater mortality or risk of complications. They have been used in different prognostic markers in COVID-19, such as the neutrophil/lymphocyte ratio and D-dimer, in which cut-off points associated with mortality and/or risk of mechanical ventilation were identified. The ROC curve is used to evaluate the diagnostic performance of a test in isolation, but it can also be used to compare the performance of two or more diagnostic tests and define which one is more accurate. This article describes the basic concepts for the use and interpretation of the ROC curve, the interpretation of an area under the curve (AUC) and the comparison of two or more diagnostic tests.

El uso de pruebas diagnósticas para determinar la presencia o ausencia de una enfermedad es esencial en la práctica clínica. Los resultados de una prueba diagnóstica pueden corresponder a estimaciones numéricas que requieren parámetros cuantitativos de referencia para trasladarse a una interpretación dicotómica como normal o anormal y así, implementar acciones para la atención de una condición o una enfermedad. Por ejemplo, en el diagnóstico de anemia es necesario definir un punto de corte para la variable hemoglobina y crear dos categorías que distingan la presencia o no de anemia. El método utilizado para este proceso es la elaboración de curvas de rendimiento diagnóstico, mejor conocidas por sus siglas en inglés como ROC (Receiver Operating Characteristic). La curva ROC además es útil como marcador pronóstico, ya que permite definir el punto de corte de una variable cuantitativa que se asocia a mayor mortalidad o riesgo de complicaciones. Se han usado en distintos marcadores pronósticos en COVID-19, como el índice neutrófilos/linfocitos y dímero D, en los que se identificaron puntos de corte asociados a mortalidad y/o riesgo de ventilación mecánica. La curva ROC se utiliza para evaluar el rendimiento diagnóstico de una prueba de forma aislada, pero también se puede usar para comparar el rendimiento de dos o más pruebas diagnósticas y definir aquella que es más precisa. En este artículo se describen los conceptos básicos para el uso e interpretación de la curva ROC, la interpretación de un área bajo la curva (ABC) y la comparación de dos o más pruebas diagnósticas.

Procalcitonin and C-reactive protein: markers in the early diagnosis of anastomotic leak.

OBJECTIVE: To determine the efficacy of serum procalcitonin (PCT) and C-reactive protein (CRP) in the early diagnosis of anastomotic leak (AL) in patients undergoing colorectal surgery. METHOD: Diagnostic test in a tertiary care hospital. Patients who did not have preoperative measurements of PCT and CRP were excluded. Those with postoperative infection not related to AL were eliminated. The diagnostic efficacy measures were sensitivity (Sn), specificity (Sp), positive (PPV) and negative (NPV) predictive values, positive (LR+) and negative (LR-) likelihood ratios, and area under the receiver operating characteristic curve (AUROC). RESULTS: Thirty-nine patients were analyzed; six had AL (15.4%). PCT and CRP increased on the second postoperative day, only in patients with AL. The cut-off points at the second postoperative day were 1.55 ng/mL for PCT and 11.25 mg/L for CRP. The most efficacious test was PCR at second postoperative day (AUROC: 1.00; Sn: 100%; Sp: 96.7%; PPV: 85.7%; NPV: 100%; LR+: 33.0). CONCLUSIONS: CRP at second postoperative day was the most effective test in the early diagnosis of AL in patients undergoing colorectal surgery, with a cut-off point lower than that reported in the international literature.

OBJETIVO: Determinar la eficacia de la procalcitonina (PCT) y la proteína C reactiva (PCR) séricas en el diagnóstico de fuga anastomótica (FA) en los pacientes sometidos a cirugía colorrectal. MÉTODO: Prueba diagnóstica en un hospital de tercer nivel. Se excluyeron los pacientes que no tuvieron mediciones preoperatorias de PCT y PCR. Se eliminaron los que cursaron con infección posoperatoria no relacionada con FA. Las medidas de eficacia diagnóstica fueron sensibilidad (S), especificidad (E), valores predictivos positivo (VPP) y negativo (VPN), razones de verosimilitud positiva (RV+) y negativa (RV−), y área bajo la curva característica operativa del receptor (AUROC). RESULTADOS: Se analizaron 39 pacientes, de los cuales 6 (15.4%) tuvieron FA. La PCT y la PCR aumentaron al segundo día posoperatorio solo en los pacientes con FA. Los puntos de corte al día 2 fueron 1.55 ng/ml para PCT y 11.25 mg/l para PCR. La prueba más eficaz fue la PCR al día 2 (AUROC: 1.00; S: 100%; E: 96.7%; VPP: 85.7%; VPN: 100%; RV+: 33.0). CONCLUSIONES: La PCR en el segundo día posoperatorio fue la prueba más eficaz en el diagnóstico temprano de FA en los pacientes sometidos a cirugía colorrectal, con un punto de corte inferior a lo reportado en la literatura internacional.

Clinimetric properties of the Perme Intensive Care Unit Mobility Score -a multicenter study for minimum important difference and responsiveness analysis

Background: The use of instruments in clinical practice with measurement properties tested is highly recommended, in order to provide adequate assessment and measurement of outcomes. Objective: To calculate the minimum clinically important difference (MCID) and responsiveness of the Perme Intensive Care Unit Mobility Score (Perme Score). Methods: This retrospective, multicentric study investigated the clinimetric properties of MCID, estimated by constructing the Receiver Operating Characteristic (ROC). Maximizing sensitivity and specificity by Youden's, the ROC curve calibration was performed by the Hosmer and Lemeshow goodness-of-fit test. Additionally, we established the responsiveness, floor and ceiling effects, internal consistency, and predictive validity of the Perme Score. Results: A total of 1.200 adult patients records from four mixed general intensive care units (ICUs) were included. To analyze which difference clinically reflects a relevant evolution we calculated the area under the curve (AUC) of 0.96 (95% CI: 0.95-0.98), and the optimal cut-off value of 7.0 points was established. No substantial floor (8.8%) or ceiling effects (4.9%) were observed at ICU discharge. However, a moderate floor effect was observed at ICU admission (19.3%), in contrast to a very low incidence of ceiling effect (0.6%). The Perme Score at ICU admission was associated with hospital mortality, OR 0.86 (95% CI: 0.82-0.91), and the predictive validity for ICU stay presented a mean ratio of 0.97 (95% CI: 0.96-0.98). Conclusion: Our findings support the establishment of the minimum clinically important difference and responsiveness of the Perme Score as a measure of mobility status in the ICU.

Antecedentes: Se recomienda encarecidamente el uso de instrumentos en la práctica clínica con propiedades de medición probadas, con el fin de proporcionar una evaluación y medición adecuada de los resultados. Objetivo: Calcular la diferencia mínima clínicamente importante (MCID) y la capacidad de respuesta de la puntuación de movilidad de la unidad de cuidados intensivos de Perme (Perme Score). Métodos: Este estudio multicéntrico retrospectivo investigó las propiedades clinimétricas de MCID, estimadas mediante la construcción de la característica operativa del receptor (ROC). Maximizando la sensibilidad y especificidad mediante la prueba de Youden, la calibración de la curva ROC se realizó mediante la prueba de bondad de ajuste de Hosmer y Lemeshow. Además, establecimos la capacidad de respuesta, los efectos suelo y techo, la consistencia interna y la validez predictiva del Perme Score. Resultados: Se incluyeron un total de 1,200 registros de pacientes adultos de cuatro unidades de cuidados intensivos (UCI) generales mixtas. Para analizar qué diferencia refleja clínicamente una evolución relevante calculamos el área bajo la curva (AUC) de 0.96 (95% CI: 0.95-0.98); y se estableció el valor de corte óptimo de 7.0 puntos. No se observaron efectos suelo (8.8%) o techo (4.9%) sustanciales al alta de la UCI. Sin embargo, se observó un efecto suelo moderado al ingreso en la UCI (19.3%), en contraste con una incidencia muy baja del efecto techo (0.6%). El Perme Score al ingreso en UCI se asoció con la mortalidad hospitalaria, OR 0.86 (95% CI: 0.82-0.91), y la validez predictiva de estancia en UCI presentó una relación media de 0.97 (95% CI: 0.96-0.98). Conclusiones: Nuestros hallazgos respaldan el establecimiento de la diferencia mínima clínicamente importante y la capacidad de respuesta de el Perme Score como medida del estado de movilidad en la UCI.

Validación de test diagnósticos (segunda parte). Test cuantitativos / Validation of diagnostic tests (part II). Quantitative tests

En esta segunda parte sobre la validación de los test diagnósticos vamos a estudiar cómo analizar la bondad delos test diagnósticos cuantitativos. El análisis de estos test se realiza a partir de las curvas ROC (Receiver Operatingcharacteristic Curve). Constituye un método para determinar la exactitud diagnóstica de test que utilizan escalascontinuas. A partir de estas curvas analizaremos dos conceptos: la AUC (Area Under Curve) y el índice de Youden,que nos ayudará a una mejor interpretación de la validez de una prueba diagnóstica y su punto de corte.(AU)

In this second part on the validation of diagnostic tests we are going to study how to analyze the goodness ofquantitative diagnostic tests. The analysis of these tests is performed from the ROC curves (Receiver Operatingcharacteristic Curve). It constitutes a method to determine the diagnostic accuracy of tests that use continuousscales. From these curves we will analyze two concepts: the AUC (Area Under Curve) and the Youden index, whichwill help us to better interpret the validity of a diagnostic test and its cut-off point.(AU)

Precisión diagnóstica de una versión abreviada de las pruebas de patrones de frecuencia y patrones de duración para la evaluación del ordenamiento auditivo temporal / Diagnostic accuracy of an abbreviated version of the frequency pattern and duration pattern tests for the evaluation of auditory temporal ordering

Introducción: Las pruebas de patrones de frecuencia y patrones de duración son consideradas los gold standard de evaluación del ordenamiento auditivo temporal. A pesar de su amplia difusión, la extensión y duración de estas pruebas dificultan su utilización dentro de baterías de evaluación del procesamiento auditivo. Sin embargo, dadas sus características estructurales, pareciera ser posible reducirlas sin perder su precisión diagnóstica. Objetivo: Determinar las propiedades diagnósticas de versiones abreviadas de las pruebas de patrones de frecuencia y patrones de duración. Material y Método: Se realizó un estudio transversal de diseño observacional analítico. Se evaluaron 166 oídos de 88 sujetos con edades entre 18 y 33 años, los cuales fueron clasificados con normalidad o alteración del ordenamiento auditivo temporal. Se utilizaron las pruebas originales de Auditec de 30 ítems por oído como referencia y los primeros 10 ítems de cada oído como versión abreviada. Resultados: La versión abreviada de la prueba de patrones de frecuencia obtuvo una sensibilidad de un 94,33%, una especificidad del 94,29% y un área bajo la curva ROC de 0,980. La versión abreviada de la prueba de patrones de duración obtuvo una sensibilidad de un 89,58%, especificidad del 71,88% y un área bajo la curva ROC de 0,916. Ambas versiones tuvieron un índice de concordancia adecuado. Conclusiones: Las versiones abreviadas de la prueba de patrones de frecuencia y patrones de duración cuentan con excelentes propiedades diagnósticas para la evaluación del ordenamiento auditivo temporal y pueden ser utilizadas de manera intercambiable con las versiones originales.

Introduction: The frequency and duration pattern tests are considered the gold standard for assessing auditory temporal ordering. Despite their wide dissemination, the length and duration of these tests make it difficult to use them within auditory processing assessment batteries. However, given their structural characteristics, reducing them without losing their diagnostic accuracy seems possible. Aim: Determine the diagnostic properties of abbreviated versions of the Frequency Patterns and Duration Patterns tests. Material and Method: A cross-sectional study with an analytical observational design was carried out. 166 ears of 88 subjects aged between 18 and 33 years were evaluated, classified as normal or altered in temporal auditory order. The original Auditec tests of 30 items per ear were used as a reference, and the first 10 items of each ear as an abbreviated version. Results: The abbreviated version of the frequency patterns test obtained a sensitivity of 94.33%, a specificity of 94.29%, and an area under the ROC curve of 0.980. The abbreviated version of the duration pattern test obtained a sensitivity of 89.58%, a specificity of 71.88%, and an area under the ROC curve of 0.916. Both versions had an adequate concordance index. Conclusion: The abbreviated versions of the frequency patterns and duration patterns test have excellent diagnostic properties for assessing auditory temporal ordering and can be used interchangeably with the original versions.

La curva ROC / ROC curve

La curva ROC es una herramienta estadística que se utiliza para evaluar la capacidad discriminativa de una prueba diagnóstica dicotómica. Se trata de curvas en las que se presenta la sensibilidad en función de los falsos positivos (complementario de la especificidad) para distintos puntos de corte. Son útiles para elegir el punto de corte más adecuado de una prueba, conocer el rendimiento global de esta y comparar la capacidad discriminativa de 2 o más pruebas diagnósticas. (AU)

The ROC curve is a statistical tool used to evaluate the discriminative capacity of a dichotomous diagnostic test. These are curves in which sensitivity is presented as a function of false positives (complementary to specificity) for different cut-off points. They are useful for choosing the most appropriate cut-off point for a test, knowing its overall performance and comparing the discriminative capacity of 2 or more diagnostic tests. (AU)

[ROC curve]. / La curva ROC.

The ROC curve is a statistical tool used to evaluate the discriminative capacity of a dichotomous diagnostic test. These are curves in which sensitivity is presented as a function of false positives (complementary to specificity) for different cut-off points. They are useful for choosing the most appropriate cut-off point for a test, knowing its overall performance and comparing the discriminative capacity of 2 or more diagnostic tests.

Timed Up and Go na avaliação da fragilidade de pessoas idosas agricultoras do Rio Grande do Sul: estudo transversal / Timed Up and Go in assessing the frailty of older farmers in Rio Grande do Sul: cross-sectional study

Resumo Objetivos Avaliar a sensibilidade do teste Timed Up and Go test (TUG) como preditor da síndrome da fragilidade do idoso (SFI) da população rural idosa do Rio Grande do Sul (RS) e identificar a prevalência de SFI nessa população. Método Estudo transversal, realizado com 604 agricultores com mais de 60 anos de idade (321 homens e 283 mulheres) identificados por meio de conglomerados estruturados a partir das regionais da Federação dos Trabalhadores da Agricultura do Rio Grande do Sul (FETAG-RS) e respectivos sindicatos. Além de variáveis demográficas (sexo, idade), foi avaliada a mobilidade funcional mediante a realização do TUG e a fragilidade referida. A curva Receiver-Operating Characteristic (ROC) foi construída para avaliar um ponto de corte do teste TUG para fragilidade. Resultados A SFI ou fragilidade foi identificada em 52,5% (n=317) da população pesquisada; 35,1% (n=212) pré-frageis e 12,4% (n=75) não-frágeis. E o tempo médio de realização do TUG em relação ao sexo foi de 11,6 segundos para mulheres e 10,8 segundos para homens (p=0,0001). A progressão da idade esteve relacionada com maior tempo de realização do teste (idosos jovens - 60-64 anos; idosos mais velhos -75-79 e longevos - 80+ - p=0,0001). A curva ROC indicou 10 segundos na execução do teste TUG como melhor ponto de corte para diagnóstico da SF em idosos rurais. Conclusão A frequência de fragilidade e pré-fragilidade nesta pesquisa, indicam uma condição de vulnerabilidade do trabalhador rural do RS no seu processo de envelhecimento. Demonstrando, a partir do teste TUG, características de mobilidade funcional e risco de fragilidade dos agricultores mais velhos, importantes para considerações futuras sobre as singularidades da saúde dessa população e intervenções profissionais necessárias.

Abstract Objectives To evaluate the sensitivity of the Timed Up and Go test (TUG) as a predictor of frailty syndrome in the elderly (IFS) in the elderly rural population of Rio Grande do Sul (RS) and to identify the prevalence of IFS in this population. Method Cross-sectional study, carried out with 604 farmers over 60 years of age (321 men and 283 women) identified through clusters structured from the regions of the Federation of Agricultural Workers of Rio Grande do Sul (FETAG-RS) and respective unions. In addition to demographic variables (gender, age), functional mobility was assessed by performing the TUG and reported frailty. The Receiver-Operating Characteristic (ROC) curve was constructed to assess a TUG test cutoff point for frailty. Results IFS or frailty was identified in 52.5% (n=317) of the surveyed population; 35.1% (n=212) pre-frail and 12.4% (n=75) non-frail. And the mean time to perform the TUG varied according to gender was 11.6 seconds for women and 10.8 seconds for men - (p=0.0001). The progression of age was related to longer time spent on the age test (young elderly - 60-64 years old; older elderly -75-79 and oldest old - 80+ - p=0.0001). The ROC curve indicated 10 seconds in the execution of the TUG test as the best cutoff point for diagnosing the SF frailty syndrome in rural elderly. Conclusion The frequency of frailty and pre-frailty in this research indicates a condition of vulnerability of rural workers in RS in their aging process. Demonstrating, from the TUG test, characteristics of functional mobility and risk of frailty of older farmers, important for future considerations on the singularities of the health of this population and necessary professional interventions.

Teste de força máxima de preensão palmar em pessoas idosas longevas do sudeste brasileiro: definição de pontos de corte / Maximum handgrip strength test in long-lived elderly people from southeastern Brazil: definition of cutoff points

Resumo Objetivo Definir pontos de corte para os valores do teste de força máxima de preensão palmar (FMPP) em pessoas idosas longevas. Método Estudo transversal com amostra de pessoas idosas longevas, octogenárias e nonagenárias, saudáveis e independentes funcionais (grupo robusto) e frágeis (grupo frágil). O teste de FMPP foi realizado em triplicata, sendo considerado o maior valor obtido. Os valores de sensibilidade, especificidade e os pontos de corte foram calculados por meio da Curva Característica de Operação do Receptor (ROC). Foram utilizados os pontos de corte brasileiros e os do Consenso Europeu de Sarcopenia para estudo da comparação. Resultados Foram avaliadas 121 pessoas idosas, com idade média de 84,5±5,3 anos, 65 (53,7%) do sexo feminino, sendo 46 (38%) do grupo frágil e 75 (62%) do grupo robusto. Foram encontrados os pontos de corte para FMPP de 27 kgf para homens e 19 kgf para mulheres. Os valores de sensibilidade e especificidade para os pontos de corte masculinos foram 94,44 e 65,79, respectivamente. Para o sexo feminino foram de 85,71 e 67,57. A partir desses pontos de corte, 23 (38,3%) pessoas idosas do grupo robusto foram classificadas com força inadequada, e, portanto, com provável sarcopenia, ao passo que, de acordo com os pontos de corte brasileiros e europeus, o número é de 35 (44,3%) e 14 (33,3%), respectivamente. Conclusão O estudo definiu pontos de corte para a população longeva e mostrou que os pontos de corte definidos até o momento para a população idosa brasileira não se mostraram adequados para longevos.

Abstract Objective To define cut-off points for the values ​​of the Maximum Handgrip Strength (MGS) test in long-lived elderly people. Method Cross-sectional study with a sample of long-lived elderly people, octogenarians and nonagenarians, healthy and functionally independent (robust group) and frail (fragile group). The MHS test was performed in triplicate, with the highest value obtained being considered. Sensitivity, specificity and cut-off values ​​were calculated using the Receiver Operating Characteristic Curve (ROC). The Brazilian cut-off points and those of the European Consensus on Sarcopenia were used for the comparison study. Results 121 elderly people were evaluated, with a mean age of 84.5±5.3 years, 65 (53.7%) female, 46 (38%) from the frail group and 75 (62%) from the robust group. Cut-off points for MHS of 27 kgf for men and 19 kgf for women were found. Sensitivity and specificity values ​​for men's cutoffs were 94.44 and 65.79, respectively. For woman, they were 85.71 and 67.57. Based on these cutoff points, 23 (38.3%) individuals from the robust group were classified as having competitive strength, and therefore with probable sarcopenia, while according to the Brazilian and European cutoff points, the number is 35 (44.3%) and 14 (33.3%). Conclusion The study defined cut-off points for the oldest-old population and showed that the cut-off points defined so far for the Brazilian elderly population were not adequate for the oldest-old.

Risk of sarcopenia in older adults with type 2 diabetes mellitus: evaluation of the SARC-F and SARC-CalF as screening tools / Risco de sarcopenia em idosos com diabetes mellitus tipo 2: avaliação do SARC-F e SARC-CalF como ferramentas para rastreamento

Objective: To evaluate the diagnostic power of SARC-F and SARC-CalF as screening tools for sarcopenia risk in older adults with type 2 diabetes mellitus. Methods: This cross-sectional study of 128 patients was conducted at the endocrinology outpatient clinic of a hospital in Recife, Brazil between July 2022 and February 2023. Sarcopenia was diagnosed according to original and updated European Consensus criteria for older adults. Muscle mass was assessed with electrical bioimpedance, muscle strength was assessed with a handgrip test, and physical performance was assessed with gait speed. Sarcopenia risk was assessed using the SARC-F and SARC-CalF instruments. The sensitivity, specificity, positive and negative predictive values, receiver operating characteristic curve, and area under the curve were analyzed to determine the best diagnostic performance. Results: According to the original and updated versions of the European Consensus criteria, the prevalence of sarcopenia was 25.00% and 10.90%, respectively. Sarcopenia risk was 17.20% according to the SARC-F and 23.40% according to the SARC-CalF. The sensitivity and specificity of the SARC-F ranged from 12.55% to 36.11% and 71.87% to 92.39%, respectively, while those of the SARC-CalF ranged from 47.22% to 85.71% and 82.46% to 88.89%, respectively. The area under the curve for the SARC-F and SARC-CalF varied between 0.51 and 0.71 and 0.67 and 0.86, respectively. Conclusions: The SARC-CalF had better diagnostic performance for all analyzed diagnostic criteria. Adding calf circumference to the SARC-F was an effective screening method for sarcopenia risk in the study population

Objetivo: Avaliar o poder diagnóstico do SARC-F e SARC-CalF como ferramentas de rastreamento para o risco de sarcopenia em idosos com diabetes mellitus tipo 2. Metodologia: Estudo transversal com 128 pacientes desenvolvido no ambulatório de endocrinologia de um hospital do Recife entre julho de 2022 e fevereiro de 2023. A sarcopenia foi diagnosticada de acordo com os critérios do Consenso Europeu para sarcopenia em pessoas idosas e sua versão atualizada. Foi realizada bioimpedância elétrica para avaliar a massa muscular, teste de preensão palmar para a força muscular e teste de velocidade de marcha para a performance física. O risco para sarcopenia foi avaliado por meio do SARC-F e SARC-CalF. Realizou-se análise de sensibilidade, especificidade, valores preditivos positivos e negativos, curva Característica de Operação do Receptor (ROC) e área sob a curva (AUC) para determinar a melhor performance diagnóstica. Resultados: A prevalência de sarcopenia foi de 25,00% de acordo com a primeira versão do Consenso Europeu e 10,90% considerando a versão atualizada. O risco para sarcopenia foi de 17,20% (SARC-F) e 23,40% (SARC-CalF). A sensibilidade do SARC-F variou entre 12,55 e 36,11%, e a espec ificidade entre 71,87 e 92,39%, enquanto o SARC-CalF apresentou sensibilidade entre 47,22 e 85,71% e especificidade entre 82,46 e 88,89%. A AUC do SARC-F variou entre 0,51 e 0,71, enquanto o SARC-CalF ficou entre 0,67 e 0,86. Conclusões: O SARC-CalF apresentou melhor performance diagnóstica quando comparado a todos os critérios diagnósticos analisados. A adição da circunferência da panturrilha é um método eficaz para o rastreamento do risco de sarcopenia na população do estudo

Diffusion tensor imaging-derived biomarkers performance in glioblastoma tumor regions: exploratory data analysis using zombie plots and diagnostic tests.

INTRODUCTION: Using diffusion tensor imaging (DTI), 11 biomarkers have been reported in different glioblastoma (GB) regions. OBJECTIVE: To compare the efficacy of GB biomarkers using "zombie plots". METHODS: Retrospective cohort of 29 subjects with GB who underwent 3-Tesla brain magnetic resonance imaging. DTI major, intermediate and minor eigenvalues were used to calculate biomarkers at five tumor regions: normal-appearing white matter (NAWM), proximal and distal edema, tumor tissue and necrosis. Contingency tables with true and false positive and negative results allowed the calculation of zombie plots based on the Bayes factor and previously unreported diagnostic tests. RESULTS: The MD, FA, q, L, Cl, Cp and RA biomarkers had a good performance at the optimal zone for NAWM diagnosis. The proximal and distal edema, enhancing rim and necrosis regions do not have biomarkers that identify them with an optimal performance level. CONCLUSIONS: Zombie plots allow simultaneous comparison of biomarkers based on likelihood ratios. MD, FA, q, L, Cl, Cp, RA discriminated NAWM normal brain tissue at the optimal zone, but performance for other regions was at the mediocre, diagnostic inclusion and diagnostic exclusion zones.

INTRODUCCIÓN: Han sido reportados 11 biomarcadores de imágenes con tensor de difusión (DTI) en las regiones tumorales del glioblastoma. OBJETIVO: Comparar la eficacia de biomarcadores de glioblastoma mediante gráficos de zombie, que permiten la comparación simultánea en función de razones de verosimilitud. MÉTODOS: Cohorte retrospectiva de 29 sujetos con glioblastoma a quienes se efectuó resonancia magnética cerebral de 3 T. Los eigenvalores mayor, intermedio y menor de ITD se utilizaron para calcular 11 biomarcadores en cinco regiones tumorales: sustancia blanca de apariencia normal (NAWM), edema proximal y distal, tumoral viable y necrosis. Las tablas de contingencia con resultados verdaderos y falsos positivos y negativos permitieron calcular gráficos de zombie basados en el factor de Bayes y pruebas diagnósticas previamente no reportadas. RESULTADOS: Los biomarcadores DM, AF, q, L, Cl, Cp, AR actúan en la zona óptima para el diagnóstico de NAWM. Las regiones de edema proximal y distal, tejido tumoral que se realza con contraste y necrosis no poseen biomarcadores que las identifiquen en un nivel de rendimiento óptimo. CONCLUSIONES: Los biomarcadores DM, AF, q, L, Cl, Cp, AR discriminan el tejido cerebral normal en la zona óptima, pero el rendimiento de otras regiones tumorales se ubica en las zonas de inclusión diagnóstica, exclusión diagnóstica y mediocre.

Anthropometric indicators of obesity for the prediction of metabolic syndrome in the older adults / Indicadores antropométricos de obesidade na predição de síndrome metabólica em idosos

INTRODUCTION: The anthropometric indicators of obesity may be important in predicting metabolic syndrome (MS). OBJECTIVE: To evaluate the anthropometric indicators as predictors of MS and verify the association of these indicators with MS in older adult individuals of both sexes. METHODS: Cross-sectional epidemiological study was carried out with 222 individuals aged 60 years or older residents in the urban area of Aiquara, Bahia state, Brazil. Older adults were measured for anthropometric indicators: body mass index (BMI), waist-to-height ratio (WHtR), waist circumference, conicity index, the sum of skinfolds; blood pressure; biochemical variables: fasting glucose, triglycerides, total cholesterol, and fractions. For the diagnosis of MS, the definition of the International Diabetes Federation was used. Descriptive and inferential data analysis was tested using correlation, the Poisson regression technique, and the Receiver Operating Characteristic (ROC) curve. RESULTS: The prevalence of MS was 62.3%. There was a correlation of all anthropometric indicators with MS in both sexes. The indicators of visceral fat had a strong association in that these indicators had an area under the ROC curve higher than 0.76 (CI95% 0.66­0.85). Thus, most results showed a weak correlation. CONCLUSION: All anthropometric indicators can be used to predict MS in older adults for both sexes, however, BMI and WHtR showed the best predictions.

INTRODUÇÃO: Os indicadores antropométricos de obesidade podem ser importantes na predição da síndrome metabólica (SM). OBJETIVO: Avaliar os indicadores antropométricos como preditores da SM, bem como verificar a associação desses indicadores com a SM em idosos de ambos os sexos. MÉTODOS: Estudo epidemiológico transversal realizado com 222 indivíduos com 60 anos ou mais residentes na zona urbana de Aiquara-BA, Brasil. Os idosos foram avaliados quanto aos indicadores antropométricos: índice de massa corporal (IMC), razão cintura-estatura (RCEst), circunferência da cintura, índice de conicidade, soma de dobras cutâneas; pressão sanguínea; bioquímicos: glicemia em jejum, triglicérides, colesterol total e frações. Foram classificados quanto à presença de SM de acordo com a Federação Internacional de Diabetes. A análise descritiva e inferencial dos dados foi testada utilizando correlação, a técnica de regressão de Poisson e a curva Receiver Operating Characteristic (ROC). RESULTADOS: A prevalência de SM foi de 62,3%. Houve correlação de todos os indicadores antropométricos com a SM em ambos os sexos. Os indicadores de gordura visceral apresentaram forte associação, pois possuem área abaixo da curva ROC superior a 0,76 (IC95% 0,66-0,85). Assim, a maioria dos resultados apresentou correlação fraca. CONCLUSÃO: Todos os indicadores antropométricos podem ser usados para rastrear a SM em idosos de ambos os sexos, no entanto, o IMC e a RCEst apresentaram as melhores previsões.

Análisis de la curva ROC en la evaluación de indicadores antropométricos / Analysis of the ROC curve in the evaluation ofanthropometric indicators

Evaluación del Índice Peso-Circunferencia de Cintura (IPCC) mediante Regresión Logística. Estudio descriptivo, prospectivo y transversal, muestra 1095 adultos y adultos mayores, edad entre 20 y 96 años. Métodos: variables: edad, peso, talla, Circunferencia de Cintura (CC), IMC, Índice Cintura-Talla (ICT). Resultados: IMC similar en los dos sexos; promedios de CC e ICT mayor en grupo ≥ 65 años; IPCC mayor en grupo 20-59 años; porcentaje de riesgo del IPCC(54,1%) mayor en CC (44,7%) menor en ICT (78,2%). IPCC significativamente asociado al IMC, CC e ICT (p<0,000); valor predictivo positivo 0,92 y valor predictivo negativo 0,70, indican capacidad discriminativa; Riesgo Relativo, 1,92; el estadístico de prueba Wald indica significancia estadística para los coeficientes de ecuaciones de probabilidad de riesgo; área bajo la curva ROC es 0,803 y 0,903 (P<0,000), alta sensibilidad y especificidad. Conclusión: el IPCC puede considerarse para evaluar sobrepeso y obesidad en adultos, dada su alta capacidad discriminativa(AU)

Evaluation of the Waist Weight-CircumferenceIndex (WWCI) using Logistic Regression. Descriptive, prospective and cross-sectional study shows 1095 adults andolder adults, aged between 20 and 96 years. Methods: variables: age, weight, size, Waist Circumference (WC), BMI, Waist-SizeIndex (WSI). Results: Similar BMI in both sexes; higher WCand WSI averages in a ≥ age of 65; major WWCI in group20-59 years; WWCI risk rate (54.1%) higher in WC (44.7%)WSI (78.2%). WWSI significantly associated with BMI, WCand WSI (p<0.000); positive predictive value 0.92 and negative predictive value 0.70, indicate discriminatory capacity; RelativeRisk, 1.92; Wald test statistic indicates statistical significance for the coefficients of risk probability equations; area under theROC curve is 0.803 and 0.903 (P<0.000), high sensitivity and specificity. Conclusion: WWCI can be considered to evaluate overweight and obesity in adults, given its high discriminatory capacity(AU)

Nueva propuesta de score para el diagnóstico de apendicitis aguda en adultos / A New Score Proposal for Diagnosing Acute Appendicitis in Adults

Introducción: La apendicitis aguda es una de las causas más comunes de abdomen agudo quirúrgico y dado que sigue siendo un reto diagnóstico, dispone de diversas escalas diagnósticas. Objetivo: Determinar la superioridad del nuevo score resultante frente al score de Alvarado en el diagnóstico de apendicitis aguda. Métodos: Se realizó un estudio de pruebas diagnósticas con el uso de la base de datos del Servicio de Cirugía del Hospital Regional Docente de Trujillo, entre febrero y diciembre del año 2015. Con los datos extraídos se elaboró un nuevo score diagnóstico que fue evaluado con el informe histopatológico y luego comparado con el score de Alvarado para evaluar su aplicación. Se calculó la sensibilidad, especificidad y los valores predictivos de ambos scores. Resultados: Se incluyeron en el estudio 312 pacientes, 177 fueron hombres (56,73 por ciento) y 135 mujeres (43,27 por ciento), con edad media de 31 años (±11,3). Con un total de 267 (85,58 por ciento) pacientes con apendicitis aguda confirmada por estudio histopatológico. El nuevo score clínico resultante de una regresión logística según la prueba de Wald, estuvo compuesto por 4 variables: sexo masculino, vómitos, automedicación previa y signo de Blumberg. Los resultados del área bajo la curva para el nuevo score clínico y el score de Alvarado fueron 0,711 y 0,707, respectivamente. Conclusiones: El nuevo score clínico es superior al score de Alvarado según el área bajo la curva, pero no en un valor significativo(AU)

Introduction: Acute appendicitis is one of the most common causes of acute surgical abdomen. Since it remains a diagnostic challenge, it has several diagnostic scales available. Objective: To determine the superiority of a new resulting score versus the Alvarado score in the diagnosis of acute appendicitis. Methods: A study of diagnostic tests was carried out using the database of the surgery service of the Regional Teaching Hospital of Trujillo, between February and December 2015. With the data collected, a new diagnostic score was elaborated and assessed with the histopathological report; and then, to assess its application, it was compared with the Alvarado score. Sensitivity, specificity and predictive values of both scores were calculated. Results: 312 patients were included in the study, 177 were male (56.73 percent) and 135 were female (43.27 percent), with a mean age of 31 years (±11.3). A total of 267 (85.58 percent) patients had acute appendicitis confirmed by histopathological study. The new clinical score resulting from a logistic regression according to the Wald test was made up of four variables: male sex, vomiting, previous self-medication and Blumberg's sign. The results of the area under curve for the new clinical score and the Alvarado score were 0.711 and 0.707, respectively. Conclusions: The new clinical score is better than the Alvarado score, according to the area under curve, but not by a significant value(AU)

Desempeño de biomarcadores de las imágenes con tensor de difusión en regiones tumorales del glioblastoma. Análisis exploratorio de datos mediante gráficos de zombie y pruebas de diagnóstico / Diffusion tensor imaging-derived biomarkers performance in glioblastoma tumor regions: exploratory data analysis using zombie plots and diagnostic tests

Resumen Introducción: Han sido reportados 11 biomarcadores de imágenes con tensor de difusión (DTI) en las regiones tumorales del glioblastoma. Objetivo: Comparar la eficacia de biomarcadores de glioblastoma mediante gráficos de zombie, que permiten la comparación simultánea en función de razones de verosimilitud. Métodos: Cohorte retrospectiva de 29 sujetos con glioblastoma a quienes se efectuó resonancia magnética cerebral de 3 T. Los eigenvalores mayor, intermedio y menor de ITD se utilizaron para calcular 11 biomarcadores en cinco regiones tumorales: sustancia blanca de apariencia normal (NAWM), edema proximal y distal, tumoral viable y necrosis. Las tablas de contingencia con resultados verdaderos y falsos positivos y negativos permitieron calcular gráficos de zombie basados en el factor de Bayes y pruebas diagnósticas previamente no reportadas. Resultados: Los biomarcadores DM, AF, q, L, Cl, Cp, AR actúan en la zona óptima para el diagnóstico de NAWM. Las regiones de edema proximal y distal, tejido tumoral que se realza con contraste y necrosis no poseen biomarcadores que las identifiquen en un nivel de rendimiento óptimo. Conclusiones: Los biomarcadores DM, AF, q, L, Cl, Cp, AR discriminan el tejido cerebral normal en la zona óptima, pero el rendimiento de otras regiones tumorales se ubica en las zonas de inclusión diagnóstica, exclusión diagnóstica y mediocre.

Abstract Introduction: Using diffusion tensor imaging (DTI), 11 biomarkers have been reported in different glioblastoma regions. Objective: To compare the efficacy of glioblastoma biomarkers using "zombie plots". Methods: Retrospective cohort of 29 subjects with glioblastoma who underwent 3-Tesla brain magnetic resonance imaging. DTI major, intermediate and minor eigenvalues were used to calculate biomarkers at five tumor regions: normal-appearing white matter (NAWM), proximal and distal edema, tumor tissue and necrosis. Contingency tables with true and false positive and negative results allowed the calculation of zombie plots based on the Bayes factor and previously unreported diagnostic tests. Results: The MD, FA, q, L, Cl, Cp and RA biomarkers had a good performance at the optimal zone for NAWM diagnosis. The proximal and distal edema, enhancing rim and necrosis regions do not have biomarkers that identify them with an optimal performance level. Conclusions: Zombie plots allow simultaneous comparison of biomarkers based on likelihood ratios. MD, FA, q, L, Cl, Cp, RA discriminated NAWM normal brain tissue at the optimal zone, but performance for other regions was at the mediocre, diagnostic inclusion and diagnostic exclusion zones.

Comparación del rendimiento diagnóstico de cuatro índices de riesgo de malignidad para cáncer de ovario / Comparison of the diagnostic performance of four malignancy risk indices for ovarian cancer

Resumen OBJETIVO: Evaluar el rendimiento diagnóstico de cuatro índices de riesgo de malignidad (IRM) en la predicción de riesgo de cáncer de ovario. MATERIALES Y MÉTODOS: Estudio comparativo y retrospectivo efectuado en pacientes mayores de 18 años con tumor anexial atendidas en el Hospital Christus Muguerza Conchita y Alta Especialidad del 2016 al 2021. Para evaluar el rendimiento diagnóstico de cada índice se utilizó la curva ROC y el índice de Youden para la obtención de sensibilidad y especificidad. RESULTADOS: Se incluyeron 330 pacientes con media de edad de 38 años. Para el IRM1 una S 73.9% y E de 85.3% con punto de corte en 126; IRM2 el mejor punto de corte se estableció en 210, con una S 72.5% y E de 89.3%; IRM3 el mejor punto de corte se estableció en 125, con una S 73.9% y E 85.8%; y para el IRM4 el punto de corte fue 436, con una S 68.1% y E 89.7%. CONCLUSIONES: El IRM es un método fácil, de bajo costo y accesible para la discriminación de pacientes con probable masa anexial maligna. En la población mexicana del noreste de México puede recomendarse la aplicación de cualquiera de los índices.

Abstract OBJECTIVE: Compare the diagnostic performance of four malignancy risk indices in predicting ovarian risk at Hospital Christus Muguerza Conchita and Alta Especialidad. MATERIALS AND METHODS: Retrospective study including clinical records of patients older than 18 years with adnexal tumor treated at the Christus Muguerza Conchita and Alta Especialidad Hospital from 2016 to 2021. The ROC curve was used to evaluate the diagnostic performance of each index, through the obtaining the best cut-off point with the highest sensitivity and specificity from the Youden index. RESULTS: A total of 330 patients were included for the adnexal tumor assessment approach. The mean age of the patients was 38.8 years. For IRM1 an S 81.2% and E of 69.3% with a cut-off point at 126; IRM2 the best cut-off point was established at 210, with an S 72.5% and E of 89.3%; IRM3 the best cut-off point was established at 125, with an S 73.9% and E 85.8%; and for IRM4 the cut-off point was 436, with an S 68.1% and E 89.7%. CONCLUSIONS: MRI is an easy, low-cost and accessible method for the discrimination of patients with probable malignant adnexal mass. The use of any of the indices can be recommended in the Mexican population of northeastern Mexico.

Indicadores de aterogenicidad en la predicción del síndrome metabólico en adultos, Trujillo-Perú

RESUMEN Objetivo: Evaluar los indicadores de aterogenicidad en la predicción del síndrome metabólico. Métodos: Se realizó un estudio descriptivo, transversal en adultos de la ciudad de Trujillo en 321 personas de 25 a 65 años que acudieron a cuatro centros de salud, de julio a diciembre de 2019. El síndrome metabólico se determinó mediante criterios de la Asociación Latinoamericana de Diabetes (ALAD) 2018 y del Adult Treatment Panel III (ATP III). Resultados: La presencia de síndrome metabólico según los criterios del ALAD y ATPIII fue de 46,1% y 48,6% respectivamente. Los índices aterogénicos con valores de riesgo más prevalentes correspondieron al Colesterol No HDL 72%; Índice de Castelli 68,2% y el índice TG/HDL en 58,3% de los participantes. Tanto para el criterio ALAD como ATPIII, el índice aterogénico que mostró la mejor predicción fue el TG/HDL seguido del índice de Castelli en el caso del ATP III. Conclusión: El índice de TG/HDL es el indicador con mejor predicción del síndrome metabólico.

ABSTRACT Objective: To evaluate atherogenicity indicators in the prediction of metabolic syndrome. Methods: A descriptive, cross-sectional study was conducted in adults from the city of Trujillo in 321 people aged 25 to 65 years who accessed care at four health centers, between July-December 2019. Metabolic syndrome was determined by using criteria of the Latin American Diabetes Association (LADA) 2018 and the Adult Treatment Panel III (ATP III). Results: The presence of metabolic syndrome according to LADA and ATP III criteria was 46.1% and 48.6%, respectively. The atherogenic indexes with the most prevalent risk values corresponded to non HDL cholesterol 72%; Castelli index 68.2% and TG/HDL index in 58.3% of the participants. For both LADA and ATP III criteria, the atherogenic index that showed the best prediction was TG/HDL followed by the Castelli index in the case of ATP III. Conclusion: The TG/HDL index is the indicator with the best prediction of metabolic syndrome.

Estandarización y validación de una prueba molecular RT-LAMP in house para el diagnóstico de SARS-CoV-2 / Standardization and validation of an in house RT-LAMP molecular test for the diagnosis of SARS-CoV-2

RESUMEN Objetivos: Estandarizar una prueba RT-LAMP in house para la detección de SARS-CoV-2 y validarla con muestras de laboratorio y de campo en pacientes con sospecha clínica de COVID-19. Materiales y métodos: Se estandarizó una prueba molecular RT-LAMP in house para la detección de SARS-CoV-2 estableciéndose el límite de detección con células Vero de cepas peruanas aisladas de SARS-CoV-2. Se validó la prueba en laboratorio con 384 muestras de hisopado nasal y faríngeo (HNF) obtenidas entre marzo y julio de 2020. Para la validación de campo se obtuvieron muestras de HNF de 383 casos sintomáticos sospechosos de COVID-19. Todas las muestras fueron evaluadas por RT-LAMP y RT-qPCR. Para la validación de laboratorio y de campo se consideró como estándar de referencia al RT-qPCR, se calcularon medidas de concordancia y rendimiento diagnóstico. Resultados: El límite de detección fue consistente en los casos con umbral de ciclo (Ct) Ct < 30 en ambas pruebas, mostrando eficiencia para detectar hasta 1000 copias/µL del gen diana. Se evidenció robustez con la mitad de las concentraciones de cebadores y 20 µL de volumen final. Se identificó ausencia de amplificación para otros coronavirus humanos. La concordancia en laboratorio obtuvo un Kappa de 0,88 (IC 95%: 0,83-0,93) y en campo fue de 0,89 (IC 95%: 0,84−0,94); la sensibilidad en laboratorio fue de 87,4% (IC 95%: 80,8−92,4) y en campo fue de 88,1% (IC 95%: 81,6−92,9), la especificidad en ambos escenarios fue de 98,8% (IC 95%: 96,4−99,7). Conclusiones: La prueba RT-LAMP in house fue validada por presentar una adecuada robustez, sin reacciones cruzadas, buena concordancia y rendimiento diagnóstico comparado con el RT-qPCR.

ABSTRACT Objectives: To standardize and validate an in-house RT-LAMP test for the detection of SARS-CoV-2, based on laboratory and field assays using samples from COVID-19 suspected patients. Materials and methods: An in-house SARS-CoV-2 RT-LAMP molecular test was standardized, establishing the detection limit with Vero cells of isolated Peruvian strains of SARS-CoV-2, and the robustness to various concentrations of primers. The laboratory validation was performed with 384 nasal and pharyngeal swab samples (UFH) obtained between March and July 2020. The field validation was performed with 383 UFH obtained from COVID-19 suspected symptomatic cases. All samples were tested by RT-LAMP and RT-qPCR. The RT-qPCR was considered as the reference standard test. The concordance measures and diagnostic performance were calculated. Results: The detection limit was consistent in cases with Ct <30 in both tests, showing efficiency to detect up to 1000 copies/μL of the target gene. Robustness was evidenced with half of the primer concentrations and 20 μL of final volume. Absence of amplification was identified for other HCoVs. Concordance showed a kappa index of 0.88 (95% CI: 0.83-0.93) and 0.89 (95% CI: 0.84 - 0.94) in laboratory and field settings, respectively. The sensitivity value in the laboratory was 87.4% (95% CI: 80.8 - 92.4) and 88.1% in the field (95% CI: 81.6 - 92.9). The specificity value in both settings was 98.8% (95% CI: 96.4-99.7). Conclusions: The in-house SARS-CoV-2 RT-LAMP test was successfully validated based on its adequate robustness, no cross-reactions, good concordance, and diagnostic performance compared to RT-qPCR.