<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD Journal Publishing DTD v2.0 20040830//EN" "http://dtd.nlm.nih.gov/publishing/2.0/journalpublishing.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink" article-type="letter" dtd-version="2.0">
  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">JMIR</journal-id>
      <journal-id journal-id-type="nlm-ta">J Med Internet Res</journal-id>
      <journal-title>Journal of Medical Internet Research</journal-title>
      <issn pub-type="epub">1438-8871</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">v22i10e21505</article-id>
      <article-id pub-id-type="pmid">33124985</article-id>
      <article-id pub-id-type="doi">10.2196/21505</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Letter to the Editor</subject>
        </subj-group>
        <subj-group subj-group-type="article-type">
          <subject>Letter to the Editor</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Comment on “Facebook as a Novel Tool for Continuous Professional Education on Dementia: Pilot Randomized Controlled Trial”</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="editor">
          <name>
            <surname>Derrick</surname>
            <given-names>Thomas</given-names>
          </name>
        </contrib>
        <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>Chan</surname>
            <given-names>Windy SY</given-names>
          </name>
        </contrib>
      </contrib-group>
      <contrib-group>
        <contrib id="contrib1" contrib-type="author" corresp="yes">
          <name name-style="western">
            <surname>Saishoji</surname>
            <given-names>Yusuke</given-names>
          </name>
          <degrees>MD</degrees>
          <xref rid="aff1" ref-type="aff">1</xref>
          <address>
            <institution>Department of General Internal Medicine</institution>
            <institution>National Hospital Organization Nagasaki Medical Center</institution>
            <addr-line>Kubara 1001-1</addr-line>
            <addr-line>Omura, 856-8562</addr-line>
            <country>Japan</country>
            <phone>81 957 52 3121</phone>
            <email>yusukesaishoji@gmail.com</email>
          </address>
          <ext-link ext-link-type="orcid">https://orcid.org/0000-0001-7163-8229</ext-link>
        </contrib>
        <contrib id="contrib2" contrib-type="author">
          <name name-style="western">
            <surname>Shiroshita</surname>
            <given-names>Akihiro</given-names>
          </name>
          <degrees>MD</degrees>
          <xref rid="aff2" ref-type="aff">2</xref>
          <ext-link ext-link-type="orcid">https://orcid.org/0000-0003-0262-459X</ext-link>
        </contrib>
        <contrib id="contrib3" contrib-type="author">
          <name name-style="western">
            <surname>Tsujimoto</surname>
            <given-names>Yasushi</given-names>
          </name>
          <degrees>MD, MPH</degrees>
          <xref rid="aff3" ref-type="aff">3</xref>
          <xref rid="aff4" ref-type="aff">4</xref>
          <ext-link ext-link-type="orcid">https://orcid.org/0000-0002-7214-5589</ext-link>
        </contrib>
      </contrib-group>
      <aff id="aff1">
        <label>1</label>
        <institution>Department of General Internal Medicine</institution>
        <institution>National Hospital Organization Nagasaki Medical Center</institution>
        <addr-line>Omura</addr-line>
        <country>Japan</country>
      </aff>
      <aff id="aff2">
        <label>2</label>
        <institution>Department of Pulmonology</institution>
        <institution>Kameda Medical Center</institution>
        <addr-line>Kamogawa</addr-line>
        <country>Japan</country>
      </aff>
      <aff id="aff3">
        <label>3</label>
        <institution>Department of Nephrology and Dialysis</institution>
        <institution>Kyoritsu Hospital</institution>
        <addr-line>Kawanishi</addr-line>
        <country>Japan</country>
      </aff>
      <aff id="aff4">
        <label>4</label>
        <institution>Healthcare Epidemiology</institution>
        <institution>School of Public Health, Graduate School of Medicine</institution>
        <institution>Kyoto University</institution>
        <addr-line>Kyoto</addr-line>
        <country>Japan</country>
      </aff>
      <author-notes>
        <corresp>Corresponding Author: Yusuke Saishoji <email>yusukesaishoji@gmail.com</email></corresp>
      </author-notes>
      <pub-date pub-type="collection">
        <month>10</month>
        <year>2020</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>30</day>
        <month>10</month>
        <year>2020</year>
      </pub-date>
      <volume>22</volume>
      <issue>10</issue>
      <elocation-id>e21505</elocation-id>
      <history>
        <date date-type="received">
          <day>30</day>
          <month>6</month>
          <year>2020</year>
        </date>
        <date date-type="accepted">
          <day>1</day>
          <month>10</month>
          <year>2020</year>
        </date>
      </history>
      <copyright-statement>©Yusuke Saishoji, Akihiro Shiroshita, Yasushi Tsujimoto. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 30.10.2020.</copyright-statement>
      <copyright-year>2020</copyright-year>
      <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
        <p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited. The complete bibliographic information, a link to the original publication on http://www.jmir.org/, as well as this copyright and license information must be included.</p>
      </license>
      <self-uri xlink:href="http://www.jmir.org/2020/10/e21505/" xlink:type="simple"/>
      <related-article related-article-type="commentary-article" id="v22i6e16772" ext-link-type="doi" xlink:href="10.2196/16772" vol="22" page="e16772" xlink:type="simple">https://www.jmir.org/2020/6/e16772/</related-article>
      <related-article related-article-type="commentary" id="v22i10e24084" ext-link-type="doi" xlink:href="10.2196/24084" vol="22" page="e24084" xlink:type="simple">https://www.jmir.org/2020/10/e24084</related-article>
      <kwd-group>
        <kwd>internet-based intervention</kwd>
        <kwd>education</kwd>
        <kwd>spin bias</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <p>We read the article “Facebook as a Novel Tool for Continuous Professional Education on Dementia: Pilot Randomized Controlled Trial” by Chan et al [<xref ref-type="bibr" rid="ref1">1</xref>] with great interest. The idea that face to face education is difficult and education via the internet or social networking systems is necessary is intriguing; this is an important perspective in the midst of the COVID-19 pandemic. In the article, the editor wrote, “readers are advised to carefully assess the validity of any potential explicit or implicit claims related to primary outcomes or effectiveness”; hence, we would like to discuss some perspectives.</p>
    <p>First, the primary outcome was measured using the differences in the scores of the pre- and postintervention knowledge assessments, which comprised the 25-item Dementia Knowledge Assessment Scale (DKAS) and a formative evaluation of 20 multiple-choice questions. However, the authors’ conclusion is focused on the outcome of improving participants’ knowledge concerning a single subscale in DKAS. This interpretation might be a spin that could warp the interpretation of results and mislead readers [<xref ref-type="bibr" rid="ref2">2</xref>].</p>
    <p>Second, the article has issues with multiple testing. When tests are divided into subscales, some of them may have significant differences. To show a significant difference in the effect, corrections to the multiple tests are required [<xref ref-type="bibr" rid="ref3">3</xref>].</p>
    <p>Finally, this study is a pre and post study; therefore, a paired <italic>t</italic> test should be used instead of a two-sample <italic>t</italic> test. The two-sample <italic>t</italic> test estimates the treatment effect using only the responses at follow-up, and it does not use any information at baseline, which may be useful for increasing efficiency if the baseline and follow-up outcomes are correlated [<xref ref-type="bibr" rid="ref4">4</xref>].</p>
  </body>
  <back>
    <glossary>
      <title>Abbreviations</title>
      <def-list>
        <def-item>
          <term id="abb1">DKAS</term>
          <def>
            <p>Dementia Knowledge Assessment Scale</p>
          </def>
        </def-item>
      </def-list>
    </glossary>
    <fn-group>
      <fn fn-type="conflict">
        <p>None declared.</p>
      </fn>
    </fn-group>
    <ref-list>
      <ref id="ref1">
        <label>1</label>
        <nlm-citation citation-type="journal">
          <person-group person-group-type="author">
            <name name-style="western">
              <surname>Chan</surname>
              <given-names>Windy Sy</given-names>
            </name>
            <name name-style="western">
              <surname>Leung</surname>
              <given-names>Angela Ym</given-names>
            </name>
          </person-group>
          <article-title>Facebook as a Novel Tool for Continuous Professional Education on Dementia: Pilot Randomized Controlled Trial</article-title>
          <source>J Med Internet Res</source>
          <year>2020</year>
          <month>06</month>
          <day>02</day>
          <volume>22</volume>
          <issue>6</issue>
          <fpage>e16772</fpage>
          <comment>
            <ext-link ext-link-type="uri" xlink:type="simple" xlink:href="https://www.jmir.org/2020/6/e16772/"/>
          </comment>
          <pub-id pub-id-type="doi">10.2196/16772</pub-id>
          <pub-id pub-id-type="medline">32484441</pub-id>
          <pub-id pub-id-type="pii">v22i6e16772</pub-id>
          <pub-id pub-id-type="pmcid">PMC7298630</pub-id>
        </nlm-citation>
      </ref>
      <ref id="ref2">
        <label>2</label>
        <nlm-citation citation-type="journal">
          <person-group person-group-type="author">
            <name name-style="western">
              <surname>Boutron</surname>
              <given-names>Isabelle</given-names>
            </name>
            <name name-style="western">
              <surname>Dutton</surname>
              <given-names>Susan</given-names>
            </name>
            <name name-style="western">
              <surname>Ravaud</surname>
              <given-names>Philippe</given-names>
            </name>
            <name name-style="western">
              <surname>Altman</surname>
              <given-names>Douglas G</given-names>
            </name>
          </person-group>
          <article-title>Reporting and interpretation of randomized controlled trials with statistically nonsignificant results for primary outcomes</article-title>
          <source>JAMA</source>
          <year>2010</year>
          <month>05</month>
          <day>26</day>
          <volume>303</volume>
          <issue>20</issue>
          <fpage>2058</fpage>
          <lpage>64</lpage>
          <pub-id pub-id-type="doi">10.1001/jama.2010.651</pub-id>
          <pub-id pub-id-type="medline">20501928</pub-id>
          <pub-id pub-id-type="pii">303/20/2058</pub-id>
        </nlm-citation>
      </ref>
      <ref id="ref3">
        <label>3</label>
        <nlm-citation citation-type="journal">
          <person-group person-group-type="author">
            <name name-style="western">
              <surname>Li</surname>
              <given-names>Guowei</given-names>
            </name>
            <name name-style="western">
              <surname>Taljaard</surname>
              <given-names>Monica</given-names>
            </name>
            <name name-style="western">
              <surname>Van den Heuvel</surname>
              <given-names>Edwin R</given-names>
            </name>
            <name name-style="western">
              <surname>Levine</surname>
              <given-names>Mitchell Ah</given-names>
            </name>
            <name name-style="western">
              <surname>Cook</surname>
              <given-names>Deborah J</given-names>
            </name>
            <name name-style="western">
              <surname>Wells</surname>
              <given-names>George A</given-names>
            </name>
            <name name-style="western">
              <surname>Devereaux</surname>
              <given-names>Philip J</given-names>
            </name>
            <name name-style="western">
              <surname>Thabane</surname>
              <given-names>Lehana</given-names>
            </name>
          </person-group>
          <article-title>An introduction to multiplicity issues in clinical trials: the what, why, when and how</article-title>
          <source>Int J Epidemiol</source>
          <year>2017</year>
          <month>04</month>
          <day>01</day>
          <volume>46</volume>
          <issue>2</issue>
          <fpage>746</fpage>
          <lpage>755</lpage>
          <pub-id pub-id-type="doi">10.1093/ije/dyw320</pub-id>
          <pub-id pub-id-type="medline">28025257</pub-id>
          <pub-id pub-id-type="pii">dyw320</pub-id>
        </nlm-citation>
      </ref>
      <ref id="ref4">
        <label>4</label>
        <nlm-citation citation-type="journal">
          <person-group person-group-type="author">
            <name name-style="western">
              <surname>Yang</surname>
              <given-names>L</given-names>
            </name>
            <name name-style="western">
              <surname>Tsiatis</surname>
              <given-names>AA</given-names>
            </name>
          </person-group>
          <article-title>Efficiency Study of Estimators for a Treatment Effect in a Pretest–Posttest Trial</article-title>
          <source>The American Statistician</source>
          <year>2001</year>
          <month>11</month>
          <volume>55</volume>
          <issue>4</issue>
          <fpage>314</fpage>
          <lpage>321</lpage>
          <pub-id pub-id-type="doi">10.1198/000313001753272466</pub-id>
        </nlm-citation>
      </ref>
    </ref-list>
  </back>
</article>
