<?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>2011-0839</journal-id>
<journal-title><![CDATA[Universitas Medica]]></journal-title>
<abbrev-journal-title><![CDATA[Univ. Med.]]></abbrev-journal-title>
<issn>2011-0839</issn>
<publisher>
<publisher-name><![CDATA[Pontificia Universidad Javeriana]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2011-08392021000200005</article-id>
<article-id pub-id-type="doi">10.11144/javeriana.umed62-2.nnnt</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Número necesario a tratar y número necesario para producir daño: su importancia]]></article-title>
<article-title xml:lang="en"><![CDATA[Number Needed to Treat and Number Needed to Harm: Its Importance]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jassir Acosta]]></surname>
<given-names><![CDATA[María Paula]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gómez-Restrepo MSc, PhD]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Pontificia Universidad Javeriana Facultad de Medicina Departamento de Epidemiología Clínica y Bioestadística]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Pontificia Universidad Javeriana Facultad de Medicina ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2021</year>
</pub-date>
<volume>62</volume>
<numero>2</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S2011-08392021000200005&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S2011-08392021000200005&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S2011-08392021000200005&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Para lograr una adecuada comprensión de los resultados de un estudio de investigación en salud es importante tener claros ciertos conceptos epidemiológicos y estadísticos. El objetivo de este artículo es abordar, de manera sencilla y clara, los conceptos de número necesario a tratar y número necesario para producir daño, explicar cómo se calculan, aclarar la importancia de su interpretación y aplicación en contextos clínicos a partir de ejemplos, al igual que algunas de las limitaciones de su uso que han sido frecuentemente discutidas en la literatura.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In order to comprehend the results of research studies in health it is important to have clarity about certain epidemiologic and statistical concepts. The objective of this article is to explain, in a clear and simple manner, the concepts of the number needed to treat and number needed to harm, how to calculate these measures, the importance of the interpretations of their values and its application in clinical contexts with examples. We will also talk about the limitations of their use that have been frequently discussed in the literature.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[número necesario a tratar]]></kwd>
<kwd lng="es"><![CDATA[epidemiología]]></kwd>
<kwd lng="es"><![CDATA[bioestadística]]></kwd>
<kwd lng="en"><![CDATA[number needed to treat]]></kwd>
<kwd lng="en"><![CDATA[epidemiology]]></kwd>
<kwd lng="en"><![CDATA[biostatistics]]></kwd>
</kwd-group>
</article-meta>
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