Comparación de los resultados de pruebas de laboratorio seleccionadas de un estudio poblacional de adultos mayores de Costa Rica

Abstract

Este artículo valora las diferencias en la medición entre laboratorios de siete biomarcadores de un estudio poblacional de adultos mayores en Costa Rica, denominado CRELES. Usa los datos de ensayos replicados en varios laboratorios para la misma muestra biológica. Encuentra una alta estabilidad (medida por el coeficiente de correlación) para casi todas las pruebas, sin embargo se observan diferencias significativas en los promedios entre laboratorios, es decir existen sesgos en la medición de los biomarcadores. Los sesgos son especialmente grandes para creatinina y hemoglobina glicosilada. Las diferencias observadas entre los distintos laboratorios refuerzan el concepto de la variabilidad dependiente tanto del analito como del paciente y del método de análisis. Dadas las diferencias encontradas se definieron ecuaciones para ajustar los datos emitidos por dos laboratorios con el fin de que sean comparables con un tercer laboratorio usado como referencia. Las dicotomías en riesgo o no derivadas de los resultados de laboratorio luego del ajuste, no presentan diferencias entre laboratorios.

Metabolic control in a nationally representative diabetic elderly sample in Costa Rica: patients at community health centers vs. patients at other health care settings

“…of serum). Specimens were analyzed in several laboratories according to the methods described elsewhere [ 18 ]. Linear adjustments were performed to have comparable measurements across laboratories; technical support for the adequacy of these linear adjustments was provided by microbiologists.…”

Surprising SES Gradients in Mortality, Health, and Biomarkers in a Latin American Population of Adults

“…In addition to the internal reliability tests that these laboratories must conduct as part of their quality control procedures, we conducted reliability analyses in subsamples of 20–40 specimens that were reanalyzed for each biomarker in a different laboratory. We report elsewhere the results of these reliability analyses, as well as some adjustments introduced to standardize measures across laboratories ( Méndez-Chacón, Rosero-Bixby, Fernández-Rojas, & Barrantes-Jiménez, 2007 ).…”

Altitude and regional gradients in chronic kidney disease prevalence in Costa Rica: Data from the Costa Rican Longevity and Healthy Aging Study

“…During a second visit early the next day, fasting blood samples were collected by venipuncture: 1 EDTA purple top tube (for 3–4 ml of whole blood) and 2 serum‐separating tubes with a clot activator (for 10–12 ml of blood, to obtain 4–6 ml of serum). Specimens were analysed in several laboratories (three laboratories for serum creatinine) according to the methods described elsewhere, which include linear adjustments to have comparable measurements across laboratories . Serum creatinine measurements were calibrated using the Roche method for isotope dilution‐mass spectrometry .…”