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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">JPH</journal-id>
      <journal-id journal-id-type="nlm-ta">JMIR Public Health Surveill</journal-id>
      <journal-title>JMIR Public Health and Surveillance</journal-title>
      <issn pub-type="epub">2369-2960</issn>
      <publisher>
        <publisher-name>JMIR Publications</publisher-name>
        <publisher-loc>Toronto, Canada</publisher-loc>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id">v2i1e7</article-id>
      <article-id pub-id-type="pmid">27227161</article-id>
      <article-id pub-id-type="doi">10.2196/publichealth.5298</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Original Paper</subject>
        </subj-group>
        <subj-group subj-group-type="article-type">
          <subject>Original Paper</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Factors Associated With Condom Breakage During Anal Intercourse: A Cross-Sectional Study of Men Who Have Sex With Men Recruited in an Online Survey</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="editor">
          <name>
            <surname>Eysenbach</surname>
            <given-names>Gunther</given-names>
          </name>
        </contrib>
      </contrib-group>
      <contrib-group>
        <contrib contrib-type="reviewer">
          <name>
            <surname>Milhausen</surname>
            <given-names>Robin</given-names>
          </name>
        </contrib>
        <contrib contrib-type="reviewer">
          <name>
            <surname>Prestage</surname>
            <given-names>Garrett</given-names>
          </name>
        </contrib>
        <contrib contrib-type="reviewer">
          <name>
            <surname>Gates</surname>
            <given-names>Madison</given-names>
          </name>
        </contrib>
      </contrib-group>
      <contrib-group>
        <contrib contrib-type="author" id="contrib1" equal-contrib="yes">
          <name name-style="western">
            <surname>Kim</surname>
            <given-names>Min</given-names>
          </name>
          <degrees>MPH</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-7575-0012</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib2" corresp="yes">
          <name name-style="western">
            <surname>McKenney</surname>
            <given-names>Jennie</given-names>
          </name>
          <degrees>MPH, PhD</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <address>
            <institution>Rollins School of Public Health</institution>
            <institution>Department of Epidemiology</institution>
            <institution>Emory University</institution>
            <addr-line>1518 Clifton Road 4th Floor</addr-line>
            <addr-line>Atlanta, GA,</addr-line>
            <country>United States</country>
            <phone>1 404 727 5294</phone>
            <fax>1 404 727 5294</fax>
            <email>jennie.l.mckenney@emory.edu</email>
          </address>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0003-1377-0445</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib3">
          <name name-style="western">
            <surname>Khosropour</surname>
            <given-names>Christine M</given-names>
          </name>
          <degrees>MPH, PhD</degrees>
          <xref rid="aff2" ref-type="aff">2</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-9743-0829</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib4">
          <name name-style="western">
            <surname>Prater</surname>
            <given-names>Adam B</given-names>
          </name>
          <degrees>MPH, MD</degrees>
          <xref rid="aff3" ref-type="aff">3</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0001-9334-1688</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib5">
          <name name-style="western">
            <surname>Rosenberg</surname>
            <given-names>Eli S</given-names>
          </name>
          <degrees>PhD</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-1695-8075</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib6">
          <name name-style="western">
            <surname>Siegler</surname>
            <given-names>Aaron J</given-names>
          </name>
          <degrees>MHS, PhD</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0001-5553-7540</ext-link>
        </contrib>
        <contrib contrib-type="author" id="contrib7">
          <name name-style="western">
            <surname>Sullivan</surname>
            <given-names>Patrick S</given-names>
          </name>
          <degrees>PhD, DVM</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-7728-0587</ext-link>
        </contrib>
      </contrib-group>
      <aff id="aff1">
        <sup>1</sup>
        <institution>Rollins School of Public Health</institution>
        <institution>Department of Epidemiology</institution>
        <institution>Emory University</institution>
        <addr-line>Atlanta, GA</addr-line>
        <country>United States</country>
      </aff>
      <aff id="aff2">
        <sup>2</sup>
        <institution>University of Washington</institution>
        <institution>Department of Medicine</institution>
        <institution>University of Washinton</institution>
        <addr-line>Seattle, WA</addr-line>
        <country>United States</country>
      </aff>
      <aff id="aff3">
        <sup>3</sup>
        <institution>Emory University</institution>
        <institution>Department of Radiology and Imaging Sciences</institution>
        <institution>University of Emory</institution>
        <addr-line>Atlanta, GA</addr-line>
        <country>United States</country>
      </aff>
      <author-notes>
        <corresp>Corresponding Author: Jennie McKenney 
        <email>jennie.l.mckenney@emory.edu</email></corresp>
      </author-notes>
      <pub-date pub-type="collection">
        <season>Jan-Jun</season>
        <year>2016</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>22</day>
        <month>02</month>
        <year>2016</year>
      </pub-date>
      <volume>2</volume>
      <issue>1</issue>
      <elocation-id>e7</elocation-id>
      <!--history from ojs - api-xml-->
      <history>
        <date date-type="received">
          <day>29</day>
          <month>10</month>
          <year>2015</year>
        </date>
        <date date-type="rev-request">
          <day>19</day>
          <month>11</month>
          <year>2015</year>
        </date>
        <date date-type="accepted">
          <day>4</day>
          <month>12</month>
          <year>2015</year>
        </date>
      </history>
      <!--(c) the authors - correct author names and publication date here if necessary. Date in form ', dd.mm.yyyy' after jmir.org-->
      <copyright-statement>©Min Kim, Jennie McKenney, Christine M Khosropour, Adam B Prater, Eli S Rosenberg, Aaron J Siegler, Patrick S Sullivan. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 22.02.2016.</copyright-statement>
      <copyright-year>2016</copyright-year>
      <license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/2.0/">
        <p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Public Health and Surveillance, is properly cited. The complete bibliographic information, a link to the original publication on http://publichealth.jmir.org, as well as this copyright and license information must be included.</p>
      </license>
      <self-uri xlink:href="http://publichealth.jmir.org/2016/1/e7/" xlink:type="simple"/>
      <abstract>
        <sec sec-type="background">
          <title>Background</title>
          <p>Within the United States, HIV affects men who have sex with men (MSM) disproportionally compared to the general population. In 2011, MSM represented nearly two-thirds of all new HIV infections while representing less than 2% of the US male population. Condoms continue to be the foundation of many HIV prevention programs; however, the failure rate of condoms during anal intercourse among MSM is estimated to be 0.5% to 8%, and condom breakages leave those affected at high risk for HIV transmission.</p>
        </sec>
        <sec sec-type="objective">
          <title>Objective</title>
          <p>Estimate the frequency of condom breakage and associated demographic and behavioral factors during last act of anal intercourse using data from a national online HIV prevention survey of MSM.</p>
        </sec>
        <sec sec-type="methods">
          <title>Methods</title>
          <p>From March 19 to April 16, 2009, data were collected on 9005 MSM through an online survey of US MSM recruited through a social networking site. Using multivariable logistic regression and controlling for several demographic and sexual risk behaviors, we estimated odds ratios of the association between condom breakage and several risk factors.</p>
        </sec>
        <sec sec-type="results">
          <title>Results</title>
          <p>In the study, 8063 participants reported having at least one male sexual partner in the last 12 months. The median age of participants was 21 years (range 18-65). More than two-thirds (68.2%, 5498/8063) reported anal intercourse during last sex and 16.90% (927/5498) reported using a condom during last anal intercourse act. Condom breakage was reported by 4.4% (28/635) participants who engaged in receptive anal intercourse and 3.5% (16/459) participants who engaged in insertive anal intercourse, with an overall failure rate of 4.0% (95% CI 3.2%-6.0%). Age (adjusted odds ratio [aOR] per 5 years: 0.53 (95% CI 0.30-0.94), number of male sex partners (aOR per 5 sex partners: 1.03 (95% CI 1.00-1.08), and being high or buzzed during sex with a casual sex partner (aOR: 3.14, 95% CI 1.02-9.60) were associated with condom breakage.</p>
        </sec>
        <sec sec-type="conclusions">
          <title>Conclusions</title>
          <p>Our results indicate condom breakage is an important problem for MSM that may be more common for younger men, for men with more partners, and during sex with casual partners after alcohol consumption or drug use. A better understanding of why condom breakage occurs more often in these groups is needed to improve educational efforts. Further, during this time of expanded interest in new condom designs, consideration should be given to how condom design might minimize breakage during anal sex.</p>
        </sec>
      </abstract>
      <kwd-group>
        <kwd>MSM</kwd>
        <kwd>anal intercourse</kwd>
        <kwd>condoms</kwd>
        <kwd>condom failure</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec sec-type="introduction">
      <title>Introduction</title>
      <p>Men who have sex with men (MSM) continue to be disproportionately affected by HIV/AIDS in the United States. MSM represent less than 2% of the male population in the Unites States, but male-to-male sexual contact remains the predominant mode of HIV transmission, accounting for an estimated 65% of all new HIV diagnoses in 2011 [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>]. Further, since 2008, the proportion of HIV diagnoses attributable to male-to-male sexual contact and the rate of HIV transmission among MSM continued to increase while trends for other transmission categories and groups have remained the same or declined [<xref ref-type="bibr" rid="ref1">1</xref>-<xref ref-type="bibr" rid="ref3">3</xref>]. The high prevalence of condomless anal intercourse among MSM coupled with the fact that anal intercourse is associated with greater HIV transmission probabilities compared to vaginal intercourse provides some explanation of the large burden of disease experienced among MSM [<xref ref-type="bibr" rid="ref4">4</xref>-<xref ref-type="bibr" rid="ref9">9</xref>].</p>
      <p>Despite suboptimal utilization, male condoms have been and remain a constant in HIV prevention programs due to their effectiveness in reducing transmission of HIV/STIs when used correctly and consistently [<xref ref-type="bibr" rid="ref10">10</xref>-<xref ref-type="bibr" rid="ref17">17</xref>]. To date, however, the US Food and Drug Administration has only cleared condoms for use during vaginal intercourse and has warned against the use of condoms during anal intercourse [<xref ref-type="bibr" rid="ref18">18</xref>]. Because of the physiological differences between anal intercourse and vaginal intercourse, such as friction and compression, it is possible that condoms break differentially by application [<xref ref-type="bibr" rid="ref19">19</xref>-<xref ref-type="bibr" rid="ref20">20</xref>].</p>
      <p>Condom failure, defined as breakage or slippage of a condom during intercourse, can obviate the prevention benefit of condom usage, but data on condom failure rates and condom failure during specific sex acts have produced a wide range of failure rates [<xref ref-type="bibr" rid="ref10">10</xref>,<xref ref-type="bibr" rid="ref21">21</xref>-<xref ref-type="bibr" rid="ref28">28</xref>]. In two separate studies, D’Anna et al reported higher rates of condom breakage or slippage during vaginal intercourse among heterosexual couples (6%) compared to anal intercourse among MSM couples (3%) [<xref ref-type="bibr" rid="ref22">22</xref>,<xref ref-type="bibr" rid="ref23">23</xref>]. Other studies have shown similarly low rates of condom failure (per condom use) among those engaging in anal intercourse (2%-3%), compared to vaginal intercourse [<xref ref-type="bibr" rid="ref10">10</xref>,<xref ref-type="bibr" rid="ref24">24</xref>-<xref ref-type="bibr" rid="ref26">26</xref>].</p>
      <p>Data on predictors of condom failure among MSM is limited. Penile length and circumference, absence of lubricants, race, and lower socioeconomic status have all been associated with higher rates of condom failure [<xref ref-type="bibr" rid="ref29">29</xref>,<xref ref-type="bibr" rid="ref30">30</xref>]. Further identification of behaviors associated with condom failure is key in order to identify high-risk groups and behaviors that would benefit from targeted condom education. Using data from a national online HIV prevention survey of MSM, we aimed to document how often condom breakage was reported to occur during anal intercourse between MSM and to identify demographic and behavioral characteristics associated with condom breakage during an act of anal intercourse.</p>
    </sec>
    <sec sec-type="methods">
      <title>Methods</title>
      <sec>
        <title>Recruitment and Ethics</title>
        <p>We utilized data from the Barriers to Online Prevention Research survey of US MSM collected between March 19, 2009 and April 16, 2009. The methods have been previously reported [<xref ref-type="bibr" rid="ref31">31</xref>]. Briefly, participants were recruited from MySpace, a large social networking site, using banner advertisements. Advertisements were directed at male users of MySpace18 years or older who resided within the United States. Once the banner advertisement was clicked, individuals were screened for eligibility and provided informed consent. Eligible participants included men 18 years or older who had at least one male sex partner in the past year and were residents of the United States. Eligible men were then asked to complete a Health Insurance Portability and Accountability Act-compliant online survey on SurveyGizmo (Boulder, CO). The survey took approximately 30 to 45 minutes to complete, and no compensation was provided to participants. The study protocol was approved by the Emory University Institutional Review Board.</p>
      </sec>
      <sec>
        <title>Data Collection</title>
        <p>Participants were asked a series of questions regarding demographics, sexual history, most recent sex act, and most recent sexual partner. Specifically, participants were asked to report the number of male sexual partners in the last 12 months and if they were high or buzzed during last act sex act. Participants were also asked questions pertaining to their most recent sex partner, such as if he was a main or casual partner. A main partner was defined as someone that the participant felt committed to above all others, and a casual partner was defined as one whom the participant did not feel committed to above all others. With regard to their last sexual partner, participants were asked whether they engaged in anal and/or oral sex with him, if a condom was used, and if the condom broke during last anal intercourse. A copy of the survey items relevant to the present study can be seen in <xref ref-type="app" rid="app1">Multimedia Appendix 1</xref>.</p>
        <p>Our outcome measure, condom breakage, was assessed via a categorical response to two separate questions designed to capture both receptive and anal insertive sex acts. Men were first asked if they had receptive anal intercourse, insertive anal intercourse, or both during their last sex episode. Based on their responses, men were asked separately about condom use when they were the receptive and/or insertive partner. Questions were: “Did [your last sexual partner] use a condom the last time you had <italic>receptive</italic> anal sex?” and “Did you use a condom the last time you had <italic>insertive</italic> anal sex?” Responses for both questions included “He (I) did not use a condom,” “He (I) used a condom part of the time,” “He (I) used a condom the whole time,” “He (I) used a condom but it broke,” “Don’t know,” or “Prefer not to answer.” Condom breakage was defined as answering “He (I) used a condom but it broke” for either insertive or receptive anal sex acts with the last male sex partner of the participant.</p>
      </sec>
      <sec>
        <title>Data Analysis</title>
        <p>Data were analyzed using SAS version 9.4 (SAS Institute). Participants included in the final analysis reported engaging in receptive or insertive anal intercourse with their last male partner in the past 12 months and using a condom during last anal intercourse. Bivariate analyses were conducted to examine unadjusted correlates of condom breakage. For continuous variables, a Wilcoxon rank-sum <italic>z</italic> test (two-sided) was used due to the nonnormally distributed nature of the variables. Statistically significant covariates (<italic>P</italic> value ≤.05) were included in the final model, as were variables found to be associated with condom breakage in previous studies [<xref ref-type="bibr" rid="ref20">20</xref>-<xref ref-type="bibr" rid="ref22">22</xref>,<xref ref-type="bibr" rid="ref25">25</xref>,<xref ref-type="bibr" rid="ref32">32</xref>,<xref ref-type="bibr" rid="ref33">33</xref>].</p>
        <p>The dependent variable, condom breakage, was calculated as a proportion and modeled the event level for both receptive and insertive anal intercourse at last sex. Thus, one participant could contribute two observations (one for receptive and one for insertive sex) from his last sexual episode. Multivariable analysis was conducted using multivariable logistic regression controlling for repeated observations. Odds ratios and 95% confidence intervals were calculated for categorical variables. For continuous variables, odds ratios and confidence intervals per unit of 5 were calculated.</p>
      </sec>
    </sec>
    <sec sec-type="results">
      <title>Results</title>
      <p>A total of 9005 participants completed the initial screening questions and gave consent; 133 surveys were linked to duplicate IP addresses and were therefore excluded. Of the 8872 unique surveys completed, 62.0% (5498/8872) were completed by men who reported anal intercourse at last sex; 44.0% (3875/8872) did not know if they used a condom at last anal intercourse. A total of 10.4% (927/8872 of the surveys were completed by participants who reported condom use at last sex and thus were eligible for multivariable analysis. <xref ref-type="fig" rid="figure1">Figure 1</xref> describes how participants were classified and identified for inclusion in the analysis.</p>
      <p>Demographic information on the 927 participants who reported using a condom at last anal intercourse and the 3052 participants who reported not using a condom at last anal intercourse is provided in <xref ref-type="table" rid="table1">Table 1</xref>.</p>
      <fig id="figure1" position="float">
        <label>Figure 1</label>
        <caption>
          <p>Inclusion criteria flowchart.</p>
        </caption>
        <graphic xlink:href="publichealth_v2i1e7_fig1.png" alt-version="no" mimetype="image" position="float" xlink:type="simple"/>
      </fig>
      <table-wrap position="float" id="table1">
        <label>Table 1</label>
        <caption>
          <p>Demographic and behavioral characteristics of men at last act of anal intercourse with a male sexual partner, stratified by condom use, among participants of an online HIV prevention survey, United States, March-April 2009.</p>
        </caption>
        <table width="548" border="1" cellpadding="8" cellspacing="0" frame="void" rules="groups">
          <col width="112"/>
          <col width="146"/>
          <col width="68"/>
          <col width="74"/>
          <col width="68"/>
          <thead>
            <tr valign="top">
              <td>Characteristics</td>
              <td><break/></td>
              <td>Used condoms<sup>a</sup> <break/>(N=927) <break/>n (%)</td>
              <td>Did not use condoms<sup>a</sup> <break/>(N=3052) <break/>n (%)</td>
              <td>Total(N=3979) <break/>n (%)</td>
            </tr>
          </thead>
          <tbody>
            <tr valign="top">
              <td><bold>Race/ethnicity</bold><sup>b</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Black/African-American</td>
              <td>150 (16.3)</td>
              <td>354 (11.7)</td>
              <td>504 (12.8)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Latino/Hispanic</td>
              <td>365 (39.8)</td>
              <td>962 (31.8)</td>
              <td>1327 (33.7)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>White/Caucasian</td>
              <td>281 (30.6</td>
              <td>1375 (45.5)</td>
              <td>1656 (42.0)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Other<sup>c</sup></td>
              <td>122 (13.3)</td>
              <td>331 (11.0)</td>
              <td>453 (11.5)</td>
            </tr>
            <tr valign="top">
              <td><bold>Education</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>≤ High school diploma/GED</td>
              <td>394 (43.4)</td>
              <td>1269 (42.0)</td>
              <td>1663 (42.3)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>&gt; High school diploma/GED</td>
              <td>516 (56.7)</td>
              <td>1752 (58.0)</td>
              <td>2268 (57.7)</td>
            </tr>
            <tr valign="top">
              <td>Age (years), median (range)<sup>b</sup></td>
              <td><break/></td>
              <td>21.0 (18-65)</td>
              <td>22.0 (18-65)</td>
              <td>21.0 (18-65)</td>
            </tr>
            <tr valign="top">
              <td><bold>Sexual identity</bold><sup>b</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Heterosexual/straight</td>
              <td>669 (72.6)</td>
              <td>2366 (78.2)</td>
              <td>3035 (76.9)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Homosexual/gay</td>
              <td>236 (25.6)</td>
              <td>628 (20.8)</td>
              <td>864 (21.9)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Other<sup>d</sup></td>
              <td>17 (1.8)</td>
              <td>32 (1.1)</td>
              <td>49 (1.2)</td>
            </tr>
            <tr valign="top">
              <td>Number of male sex partners in last 12 months, median (range)<sup>b</sup></td>
              <td><break/></td>
              <td>5.0 (1-365)</td>
              <td>3.0 (1-365)</td>
              <td>4 (1-365)</td>
            </tr>
            <tr valign="top">
              <td><bold>Type of MRMSP</bold><sup>b</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Main</td>
              <td>448 (52.1)</td>
              <td>2039 (71.1)</td>
              <td>2487 (66.7)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Casual</td>
              <td>412 (47.9)</td>
              <td>829 (28.9)</td>
              <td>1241 (33.3)</td>
            </tr>
            <tr valign="top">
              <td><bold>Race/ethnicity of MRMSP</bold><sup>b</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Black/African-American</td>
              <td>157 (17.2)</td>
              <td>360 (12.0)</td>
              <td>517 (13.2)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Latino/Hispanic</td>
              <td>298 (32.7)</td>
              <td>793 (26.4)</td>
              <td>1091 (27.9)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>White/Caucasian</td>
              <td>366 (40.2)</td>
              <td>1592 (53.1)</td>
              <td>1958 (50.1)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Other<sup>c</sup></td>
              <td>90 (9.9)</td>
              <td>256 (8.5)</td>
              <td>346 (8.8)</td>
            </tr>
            <tr valign="top">
              <td><bold>Racial concordance with MRMSP</bold><sup>e</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Yes</td>
              <td>500 (55.4)</td>
              <td>1695 (56.9)</td>
              <td>2195 (56.5)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>No</td>
              <td>403 (44.6)</td>
              <td>1286 (43.1)</td>
              <td>1689 (43.5)</td>
            </tr>
            <tr valign="top">
              <td>Age of MRMSP, median (range)<sup>b</sup></td>
              <td><break/></td>
              <td>23 (18-70)</td>
              <td>24 (18-70)</td>
              <td>23 (18-70)</td>
            </tr>
            <tr valign="top">
              <td><bold>Age discrepancy with MRMSP</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Participant is at least 5 years younger</td>
              <td>232 (25.0)</td>
              <td>740 (24.3)</td>
              <td>972 (24.4)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Participant is within 5 years in age</td>
              <td>612 (66.0)</td>
              <td>2045 (67.0)</td>
              <td>2657 (66.8)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Participant is at least 5 years older</td>
              <td>83 (9.0)</td>
              <td>267 (8.8)</td>
              <td>350 (8.8)</td>
            </tr>
            <tr valign="top">
              <td><bold>MRMSP is an exchange partner</bold><sup>f</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Yes</td>
              <td>28 (3.1)</td>
              <td>64 (2.1)</td>
              <td>92 (2.3)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>No</td>
              <td>888 (96.9)</td>
              <td>2977 (97.9)</td>
              <td>3865 (97.7)</td>
            </tr>
            <tr valign="top">
              <td><bold>High or buzzed during sex</bold><sup>g</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Yes</td>
              <td>225 (25.3)</td>
              <td>681 (23.2)</td>
              <td>906 (23.7)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>No</td>
              <td>665 (74.7)</td>
              <td>2259 (76.8)</td>
              <td>2924 (76.3)</td>
            </tr>
            <tr valign="top">
              <td><bold>HIV status of MRMSP</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>HIV positive</td>
              <td>32 (5.3)</td>
              <td>116 (5.0)</td>
              <td>148 (5.1)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>HIV negative</td>
              <td>577 (94.8)</td>
              <td>2186 (95.0)</td>
              <td>2763 (94.9)</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="table1fn1">
            <p><sup>a</sup>Column percentages may not add up to 100% due to rounding; missing values were not included.</p>
          </fn>
          <fn id="table1fn2">
            <p><sup>b</sup> <italic>P</italic> value ≤.05.</p>
          </fn>
          <fn id="table1fn3">
            <p><sup>c</sup>Other races include Asian/Pacific Islander, Native American/Alaskan Native, multiple, and other races.</p>
          </fn>
          <fn id="table1fn4">
            <p><sup>d</sup>Other sexual identities include bisexual and other.</p>
          </fn>
          <fn id="table1fn5">
            <p><sup>e</sup>A participant is racially concordant with MRMSP if he/she reports the same race/ethnicity as the MRMSP.</p>
          </fn>
          <fn id="table1fn6">
            <p><sup>f</sup>Exchange partner is defined as a partner with whom the participant had sex in exchange for things they needed (eg, money, drugs, food, shelter, or transportation).</p>
          </fn>
          <fn id="table1fn7">
            <p><sup>g</sup>Includes being high or buzzed with alcohol, drugs not prescribed by a doctor, or both during sex.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <p>Most participants were members of a racial or ethnic minority: 33.7% (1327/3979) were Hispanic, 12.8% (504/3979) were black non-Hispanic, and 11.5% (453/3979) were multiracial. Most reported having attended some college, and three-quarters of all participants were aged 18 to 26 years. The median number of male sex partners in the past 12 months was 3, and over half of participants’ last male sex partners were casual partners. Nearly 20% (906/3979) of participants had used drugs or alcohol prior to engaging in sex at last sexual episode, and almost 2% (92/3979) of participants reported exchange sex with their most recent male sex partner.</p>
      <p>Of the 927 participants included in the final analysis, 69.0% (635/927) reported using a condom during receptive anal intercourse and 50.0% (459/927) reported using a condom during insertive anal intercourse. Overall, condom breakage was reported in 4.0% (44/1094 , 95% CI 3.2%-6.0%) of the total distinct episodes of anal intercourse. Condom breakage was reported by 4.4% (28/635) participants who engaged in receptive anal intercourse and 3.5% (16/459) participants who engaged in insertive anal intercourse.</p>
      <p>Results from the multivariable analysis are presented in <xref ref-type="table" rid="table2">Table 2</xref>. Younger age and being buzzed or high before or during sex with a casual partner were associated with condom breakage during last anal intercourse, while number of male sexual partners in the past year was marginally significant. Participants’ odds of condom breakage increased 3% for every 5 male sex partners reported in the past year (adjusted odds ratio 1.03, 95% CI 1.00-1.08). Participants who reported being high or buzzed at last sex with a casual sex partner had 3 times the odds of condom breakage compared to participants who reported being high or buzzed at last sex with a main partner (95% CI 1.02-9.6). The odds of condom breakage were 0.53 for every 5-year increase in age of a participant (95% CI 0.30-0.94).</p>
      <table-wrap position="float" id="table2">
        <label>Table 2</label>
        <caption>
          <p>Associations between demographic and behavioral factors and condom breakage among men who had anal intercourse with their last male sex partner, in an online HIV prevention survey, United States, March-April 2009.</p>
        </caption>
        <table width="591" border="0" cellpadding="8" cellspacing="0" rules="groups" frame="hsides">
          <col width="121"/>
          <col width="96"/>
          <col width="69"/>
          <col width="63"/>
          <col width="69"/>
          <col width="77"/>
          <thead>
            <tr valign="top">
              <td>Characteristics</td>
              <td><break/></td>
              <td>Broken condom<sup>ab</sup> <break/>(N=41) <break/>n (%)</td>
              <td>No broken<sup>ab</sup>condom <break/>(N=881) <break/>n (%)</td>
              <td>Crude odds ratio (95% CI)</td>
              <td>Adjusted odds ratio (95% CI)</td>
            </tr>
          </thead>
          <tbody>
            <tr valign="top">
              <td><bold>Race/ethnicity</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Black/African-American</td>
              <td>10 (7)</td>
              <td>139 (93)</td>
              <td>1.95 (0.79-4.80)</td>
              <td>2.13 (0.79-5.77)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Latino/Hispanic</td>
              <td>13 (4)</td>
              <td>349 (96)</td>
              <td>1.01 (0.4-2.34)</td>
              <td>0.78 (0.29-2.08)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Other<sup>c</sup></td>
              <td>8 (7)</td>
              <td>113 (93)</td>
              <td>1.92 (0.74-4.99)</td>
              <td>1.98 (0.6-5.76)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>White/Caucasian</td>
              <td>10 (4)</td>
              <td>271 (96)</td>
              <td>Referent</td>
              <td>Referent</td>
            </tr>
            <tr valign="top">
              <td><bold>Education</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>≤ High school diploma/GED</td>
              <td>19 (5)</td>
              <td>374 (95)</td>
              <td>1.32 (0.69–2.53)</td>
              <td>0.84 (0.39-1.81)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>&gt; High school diploma/GED</td>
              <td>19 (4)</td>
              <td>493 (96)</td>
              <td>Referent</td>
              <td>Referent</td>
            </tr>
            <tr valign="top">
              <td>Age (year), median (range)<sup>d</sup></td>
              <td><break/></td>
              <td>20 (18-47)</td>
              <td>21 (18-65)</td>
              <td>0.69 (0.48-1.01)</td>
              <td>0.53 (0.30-0.94)</td>
            </tr>
            <tr valign="top">
              <td><bold>Number of male sex partners in last 12 months</bold><sup>d</sup></td>
              <td><break/></td>
              <td>6 (1-364)</td>
              <td>4 (1-87)</td>
              <td>1.05 (1.02-1.07)</td>
              <td>1.03 (1.00-1.08)</td>
            </tr>
            <tr valign="top">
              <td><bold>MRMSP is an exchange partner</bold><sup>e</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Yes</td>
              <td>4 (14)</td>
              <td>24 (86)</td>
              <td>3.93 (1.29-11.91)</td>
              <td>0.63 (0.06-6.31)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>No</td>
              <td>36 (4)</td>
              <td>848 (96)</td>
              <td>Referent</td>
              <td>Referent</td>
            </tr>
            <tr valign="top">
              <td><bold>Type of MRMSP</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Main</td>
              <td>23 (5)</td>
              <td>421 (92)</td>
              <td>1.45 (0.74-2.81)</td>
              <td>See interaction</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Casual</td>
              <td>15 (4)</td>
              <td>397 (96)</td>
              <td>Referent</td>
              <td>See interaction</td>
            </tr>
            <tr valign="top">
              <td><bold>High or buzzed during sex</bold><sup>f</sup></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Yes</td>
              <td>16 (7)</td>
              <td>209 (93)</td>
              <td>2.33 (1.20-4.56)</td>
              <td>See interaction</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>No</td>
              <td>21 (3)</td>
              <td>640 (96)</td>
              <td>Referent</td>
              <td>See interaction</td>
            </tr>
            <tr valign="top">
              <td><bold>Interaction, high or buzzed during sex</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Casual partner</td>
              <td>10 (9)</td>
              <td>107 (91)</td>
              <td>―</td>
              <td>3.14 (1.02-9.60)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Main partner</td>
              <td>4 (5)</td>
              <td>82 (95)</td>
              <td>―</td>
              <td>Referent</td>
            </tr>
            <tr valign="top">
              <td><bold>Interaction, not high or buzzed during sex</bold></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
              <td><break/></td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Casual partner</td>
              <td>4 (1)</td>
              <td>274 (99)</td>
              <td>―</td>
              <td>0.31 (0.08-1.27)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>Main partner</td>
              <td>17 (5)</td>
              <td>324 (95)</td>
              <td>―</td>
              <td>Referent</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="table2fn1">
            <p><sup>a</sup>Column percentages may not add up to 100% due to rounding; missing values were not included.</p>
          </fn>
          <fn id="table2fn2">
            <p><sup>b</sup>Condom break is defined as a break in the condom during either insertive or receptive anal intercourse (or both) during last sexual activity with a male partner. No condom breakage is defined as no break in the condom at last sexual activity (with both insertive and receptive anal intercourse) with a male partner.</p>
          </fn>
          <fn id="table2fn3">
            <p><sup>c</sup>Other races include Asian/Pacific Islander, Native American/Alaskan Native, multiple, and other races.</p>
          </fn>
          <fn id="table2fn4">
            <p><sup>d</sup>Per 5-unit increase.</p>
          </fn>
          <fn id="table2fn5">
            <p><sup>e</sup>Exchange partner is defined as a partner with whom the participant had sex in exchange for things they needed (eg, money, drugs, food, shelter, or transportation).</p>
          </fn>
          <fn id="table2fn6">
            <p><sup>f</sup>Includes being high or buzzed with alcohol, drugs not prescribed by a doctor, or both during sex.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
    </sec>
    <sec sec-type="discussion">
      <title>Discussion</title>
      <sec>
        <title>Principal Findings</title>
        <p>Results from our multivariable analysis of condom breakage among US MSM revealed an overall condom breakage rate of 4%. Condom breakage rates did not differ between participants who reported receptive and insertive anal intercourse. Younger age, a greater number of sexual partners reported in the last 12 months, and being buzzed or high at last sex with a casual partner were associated with condom breakage.</p>
        <p>The overall condom breakage rate of 4% is in line with previous studies [<xref ref-type="bibr" rid="ref10">10</xref>,<xref ref-type="bibr" rid="ref14">14</xref>-<xref ref-type="bibr" rid="ref18">18</xref>], but there is considerable variability among breakage rates from prior studies [<xref ref-type="bibr" rid="ref33">33</xref>-<xref ref-type="bibr" rid="ref40">40</xref>]. Golombok et al found a condom failure rate of 2% in a group of 283 homosexual couples in the United Kingdom, but the study focused on sexual activity among long-term couples, which does not represent the MSM population [<xref ref-type="bibr" rid="ref19">19</xref>]. Our sample was younger, and more than half of sex partners were reported to be casual partners. A 6-month condom breakage risk of 31% was found in a cohort study of MSM in Atlanta, GA [<xref ref-type="bibr" rid="ref35">35</xref>]. The high frequency of condom breakage found in the aforementioned Atlanta cohort study compared to other studies is likely due to the longer recall period (6 months), allowing for a higher number of sex acts to occur. Further, the study revealed 40% of black MSM reported breakage or incomplete use; the population was twice as likely to report condom breakage as white MSM. Similar point estimates were seen from our analysis; however, our sample size was not sufficient to assess the relationship. The wide variability of condom failure rates among these studies is most likely a reflection of the diverse population of MSM and sample sizes under study [<xref ref-type="bibr" rid="ref36">36</xref>-<xref ref-type="bibr" rid="ref40">40</xref>].</p>
        <p>For every 5 male sexual partners, we found that the odds of condom breakage increased by 3%. There are likely user characteristics of participants with large numbers of sexual partners not captured by our survey that explain the statistical association with condom breakage. Participants with a larger number of male sexual partners might have engaged in more aggressive coital behaviors than those with fewer sexual partners, leading to greater stress on the condom [<xref ref-type="bibr" rid="ref41">41</xref>,<xref ref-type="bibr" rid="ref42">42</xref>]. Further, participants with a large number of male sexual partners may have a predisposition to inappropriately use lubricant, resulting in condom failure [<xref ref-type="bibr" rid="ref43">43</xref>]. MSM who report high numbers of sexual partners represent a risk group commonly targeted for behavioral interventions, as having multiple sexual partners is an established risk factor for HIV acquisition [<xref ref-type="bibr" rid="ref38">38</xref>]. Results from our study suggest that behavioral prevention interventions targeted to this high-risk group should also include more thorough condom education.</p>
        <p>Several studies demonstrated that drug and alcohol use is associated with an increased risk of HIV acquisition among heterosexual men engaging in vaginal intercourse and MSM engaging in anal intercourse [<xref ref-type="bibr" rid="ref44">44</xref>,<xref ref-type="bibr" rid="ref45">45</xref>]. Alcohol use during sex is higher among casual partners compared to main partners; however, few studies have assessed the association between condom failure and partner type, modified by alcohol and drug use before or during sex [<xref ref-type="bibr" rid="ref46">46</xref>,<xref ref-type="bibr" rid="ref47">47</xref>]. Results from our study suggest that being high or buzzed during sex with a casual partner was associated with increased odds of condom breakage compared to being high or buzzed with a main partner. Alcohol and drug use may prolong ejaculation and thereby prolong sex, increasing the risk of condom failure [<xref ref-type="bibr" rid="ref27">27</xref>]. Moreover, alcohol and drug use may impede the proper application and usage of condoms, increasing condom failure rates [<xref ref-type="bibr" rid="ref27">27</xref>]. These results suggest that public health prevention interventions need to increase awareness of the effects of drug and alcohol use during sex, specifically targeting MSM who engage in sex with casual partners.</p>
      </sec>
      <sec>
        <title>Limitations</title>
        <p>There are several limitations to this study. Most notably, our respondents are not representative of all MSM in the United States. Due to the nature of the survey, participants had to be proficient with computers, making them more likely to have a higher education and income than the general population of MSM. Our study used a cross-sectional study design to evaluate condom breakage at last intercourse and therefore did not capture condom use or breakage over time. Safe sex behaviors fluctuate over time [<xref ref-type="bibr" rid="ref31">31</xref>], making a prospective study more appropriate to capture the time-dependent nature of condom use and failure. We did not ascertain a history of lubrication use or lubrication use during last sex act. Therefore, our sample may represent men who were less likely to use lubrication, and thus, factors associated with condom breakage may actually be factors associated with lubrication use. The majority of studies that have evaluated condom failure define it as condom breakage or slippage during sex [<xref ref-type="bibr" rid="ref36">36</xref>-<xref ref-type="bibr" rid="ref39">39</xref>]. Our study only used condom breakage as a measurement of condom failure. Omission of condom slippage data resulted in our inability to report condom failure more generally. Our study uses older data; however, our finding of a condom breakage rate of 4% is in line with previous and more recent studies [<xref ref-type="bibr" rid="ref10">10</xref>,<xref ref-type="bibr" rid="ref14">14</xref>-<xref ref-type="bibr" rid="ref18">18</xref>]. Finally, responses may have been affected by social desirability bias and recall bias, resulting in misclassification of outcomes [<xref ref-type="bibr" rid="ref48">48</xref>].</p>
      </sec>
      <sec>
        <title>Conclusion</title>
        <p>Results from our study highlight condom breakage rates among a diverse sample of MSM from the United States. While condoms remain a strong component of prevention policy, our findings indicate condoms may not suffice as a sole means of reducing HIV transmission risk within the context of a high per-act transmission risk of anal sex [<xref ref-type="bibr" rid="ref6">6</xref>]. Combining condoms with other prevention modalities such as preexposure prophylaxis can help mitigate risk that occurs after condom breakage [<xref ref-type="bibr" rid="ref49">49</xref>]. Even in the context of preexposure prophylaxis, more efforts should be made to improve condom use practices that might lead to condom failure [<xref ref-type="bibr" rid="ref49">49</xref>]. MSM who report a high number of sexual partners as well as those who use drugs and/or alcohol before or during sex with a casual partner are at an increased risk for condom failure and would benefit from targeted condom education programs to help mitigate their risks. As innovation continues to occur in the design of condoms, it will be important to consider if there are new types or designs of condoms that might decrease condom breakage during anal intercourse [<xref ref-type="bibr" rid="ref49">49</xref>]. To best understand when, why, and how condom failures occur, further studies are needed to capture the time-dependent nature of condom use; these should include high-risk sexual behaviors; precoital factors, such as condom storage; and coital factors, such as duration of sex act and use of lubricants. As HIV continues to disproportionately affect United States MSM and anal intercourse remains a significant mode of HIV transmission, condom failure among this population needs to be addressed through multiple approaches.</p>
      </sec>
    </sec>
  </body>
  <back>
    <app-group>
      <app id="app1">
        <title>Multimedia Appendix 1</title>
        <p>Barriers to Online Prevention Survey.</p>
        <media xlink:href="publichealth_v2i1e7_app1.pdf" xlink:title="PDF File (Adobe PDF File), 231KB"/>
      </app>
    </app-group>
    <glossary>
      <title>Abbreviations</title>
      <def-list>
        <def-item>
          <term id="abb1">MSM</term>
          <def>
            <p>men who have sex with men</p>
          </def>
        </def-item>
      </def-list>
    </glossary>
    <ack>
      <p>This work was facilitated by the Center for AIDS Research at Emory University (P30AI050409) and funded through a CFAR-03 grant.</p>
    </ack>
    <fn-group>
      <fn fn-type="conflict">
        <p>PS is editor-in-chief of JMIR Public Health and Surveillance. This paper was handled independently by an associate editor, with PS not involved in any decision-making. Other authors have nothing to declare.</p>
      </fn>
    </fn-group>
    <ref-list>
      <ref id="ref1">
        <label>1</label>
        <nlm-citation citation-type="web">
          <source>HIV Surveillance Report, 2011</source>
          <access-date>2016-01-24</access-date>
          <publisher-name>Centers for Disease Control and Prevention</publisher-name>
          <comment>
            <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.cdc.gov/hiv/pdf/statistics_2011_hiv_surveillance_report_vol_23.pdf">http://www.cdc.gov/hiv/pdf/statistics_2011_hiv_surveillance_report_vol_23.pdf</ext-link>
            <ext-link ext-link-type="webcite" xlink:href="6emmEQSUy"/>
          </comment>
        </nlm-citation>
      </ref>
      <ref id="ref2">
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          <month>12</month>
          <day>30</day>
          <volume>363</volume>
          <issue>27</issue>
          <fpage>2587</fpage>
          <lpage>2599</lpage>
          <comment>
            <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://europepmc.org/abstract/MED/21091279"/>
          </comment>
          <pub-id pub-id-type="doi">10.1056/NEJMoa1011205</pub-id>
          <pub-id pub-id-type="medline">21091279</pub-id>
          <pub-id pub-id-type="pmcid">PMC3079639</pub-id>
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      </ref>
    </ref-list>
  </back>
</article>