<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>2448-9190</journal-id>
<journal-title><![CDATA[Revista alergia México]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. alerg. Méx.]]></abbrev-journal-title>
<issn>2448-9190</issn>
<publisher>
<publisher-name><![CDATA[Colegio Mexicano de Inmunología Clínica y Alergia A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2448-91902021000400291</article-id>
<article-id pub-id-type="doi">10.29262/ram.v68i4.1003</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Principales sesgos en la investigación clínica]]></article-title>
<article-title xml:lang="en"><![CDATA[Main biases in clinical research]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zurita-Cruz]]></surname>
<given-names><![CDATA[Jessie Nallely]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Villasís-Keever]]></surname>
<given-names><![CDATA[Miguel Ángel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Facultad de Medicina ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Instituto Mexicano del Seguro Social Centro Médico Nacional Siglo XXI Hospital de Pediatría]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<volume>68</volume>
<numero>4</numero>
<fpage>291</fpage>
<lpage>299</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2448-91902021000400291&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2448-91902021000400291&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2448-91902021000400291&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen En la elaboración de un protocolo de investigación, los autores deben tomar en cuenta los posibles errores que puedan ocurrir a lo largo del estudio. En la investigación clínica se reconocen dos tipos: los errores aleatorios y los errores sistemáticos, estos últimos se denominan sesgos. A la fecha se han descrito decenas de sesgos, por lo que este artículo tiene como objetivo describir los principales sesgos que pueden ocurrir en los estudios de investigación clínica, así como la forma para evitarlos o minimizar sus efectos. En virtud de que existen varias clasificaciones, en la presente revisión y, a fin de disponer un panorama más práctico, los sesgos se agrupan en tres: sesgos de selección, sesgos de información (o ejecución) y sesgos de confusión. Además, para una descripción más específica, se toma en cuenta el propósito del estudio: pronóstico, terapéutica, causalidad y la evaluación de una prueba diagnóstica.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In developing a research protocol, authors must consider the possible errors that may occur throughout the study. In clinical research, two types of biases are recognized: random errors and systematic errors; the latter are called biases. To date, dozens of biases have been described, which is why the purpose of this article is to describe the main biases that can occur in clinical research studies, as well as strategies to avoid them or to minimize their effects. Since there are several classifications, in order to provide a more practical overview in this review, the biases are grouped into three types: selection biases, information (or performance) biases, and confounding biases. In addition, to make it even more specific, we describe the biases considering the purpose of the research: prognosis, therapeutics, causality, and diagnostic test studies.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Errores aleatorios]]></kwd>
<kwd lng="es"><![CDATA[Errores sistemáticos]]></kwd>
<kwd lng="es"><![CDATA[Sesgos]]></kwd>
<kwd lng="es"><![CDATA[Investigación clínica]]></kwd>
<kwd lng="es"><![CDATA[Revisión]]></kwd>
<kwd lng="en"><![CDATA[Random errors]]></kwd>
<kwd lng="en"><![CDATA[Systematic errors]]></kwd>
<kwd lng="en"><![CDATA[Biases]]></kwd>
<kwd lng="en"><![CDATA[Clinical research]]></kwd>
<kwd lng="en"><![CDATA[Review]]></kwd>
</kwd-group>
</article-meta>
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