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<title>My RSS Feed</title><link>http://thesis.uib.no/index.php</link><description>Thesis blog</description><dc:language>en</dc:language><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:rights>Copyright 2008 Bernt Lindtjorn</dc:rights><dc:date>2009-04-23T17:59:57+03:00</dc:date><admin:generatorAgent rdf:resource="http://www.realmacsoftware.com/" />
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<lastBuildDate>Thu, 23 Apr 2009 18:46:29 +0300</lastBuildDate><item><title>What is a PhD?</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>About PhD degree</category><dc:date>2009-04-23T17:59:57+03:00</dc:date><link>http://thesis.uib.no/files/ef6674aa8a76b5429e273b39739bb0b0-37.php#unique-entry-id-37</link><guid isPermaLink="true">http://thesis.uib.no/files/ef6674aa8a76b5429e273b39739bb0b0-37.php#unique-entry-id-37</guid><content:encoded><![CDATA[Many ask me what a PhD is. From <a href="http://en.wikipedia.org" rel="self">Wikipedia</a>, the free encyclopedia, you can read about different types of <a href="http://en.wikipedia.org/wiki/Doctorate" rel="self">doctorate degrees.</a> Please see some citations from Wikipedia's writing about PhD. <span style="font-size:11px; color:#7D7D7D;"><br /></span><span style="font-size:11px; color:#7D7D7D;"><br /></span><span style="font-size:14px; ">The term </span><span style="font-size:14px; "><em>doctorate</em></span><span style="font-size:14px; "> comes from the </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Latin">Latin</a></span><span style="font-size:14px; "> </span><span style="font-size:14px; "><em>docere</em></span><span style="font-size:14px; ">, meaning "to teach", shortened from the full Latin title </span><span style="font-size:14px; "><em>licentia docendi</em></span><span style="font-size:14px; ">, meaning "license to teach."<br /><br />A </span><span style="font-size:14px; font-weight:bold; ">doctorate</span><span style="font-size:14px; "> is an </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Academic_degree">academic degree</a></span><span style="font-size:14px; "> that in most countries represents the highest level of formal study or research in a given field. <br /><br />Research doctorates are awarded in recognition of academic research that is publishable in a peer-refereed </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Academic_journal">academic journal</a></span><span style="font-size:14px; ">. The best-known degree of this type is that of </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Doctor_of_Philosophy">Doctor of Philosophy</a></span><span style="font-size:14px; "> (PhD, or sometimes DPhil) awarded in many countries throughout the world. In some countries it also refers to a class of degrees which qualify the holder to practice in a specific profession (such as law or medicine). The best-known example of the former is the Ph.D. (</span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Doctor_of_Philosophy">Doctor of Philosophy</a></span><span style="font-size:14px; ">), while examples of the latter include the U.S. degree of </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Doctor_of_Medicine">Doctor of Medicine</a></span><span style="font-size:14px; "> and the Dutch </span><span style="font-size:14px; color:#142EB3;"><a href="http://en.wikipedia.org/wiki/Professional_Doctorate_in_Engineering">Professional Doctorate in Engineering</a></span><span style="font-size:14px; ">. </span>]]></content:encoded></item><item><title>Some rules when reporting numbers:</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Publishing</category><dc:date>2009-04-13T14:53:55+03:00</dc:date><link>http://thesis.uib.no/files/a431b4221aad3dea5abb6f11d869c28b-35.php#unique-entry-id-35</link><guid isPermaLink="true">http://thesis.uib.no/files/a431b4221aad3dea5abb6f11d869c28b-35.php#unique-entry-id-35</guid><content:encoded><![CDATA[There are some general rules on how to report epidemiological and statistical results. Some of these rules are:<br /><ul class="disc"><li>Numbers less than 10 are words (In our study, seven men did not complete the treatment)</li><li>Numbers 10 or more are numbers	(There were 345 children in the study)</li><li>In a sentence, numbers below 10 that are listed with numbers 10 and above should be expressed in numbers ((In our study, 20 girls and 4 boys were anaemic).</li><li>Use words to express any number that begins a sentence, title or deading. Try to avoid starting a sentence with a number (Twenty four per cent of the patients were malnourished)</li><li>Numbers that represent mathematical or statistical functions should be written as numbers (We multiplied the scores with 3).</li><li>Use a zero before decimal points when numbers are less than 1. (The P value was 0.012)</li><li>Do not use space between a number and the percent sign (In total, 33% of the participants were obese)</li><li>Use one space between a number and its unit (The mean weight of women was 62.5 kg)</li><li>The P value is with capital P. (The P value was 0.012)</li><li>P values between 0.001 and 0.05 should be reported with three decimal points (More girls than boys were malnourshed (t=3.0, df 45, P = 0.004).</li><li>P values reported on a computer output as 0.000 should be reported as P < 0.001.</li></ul>]]></content:encoded></item><item><title>Data analysis</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2009-03-29T14:26:34+03:00</dc:date><link>http://thesis.uib.no/files/11c4c728cc5d50b7a1758c6585f0528d-34.php#unique-entry-id-34</link><guid isPermaLink="true">http://thesis.uib.no/files/11c4c728cc5d50b7a1758c6585f0528d-34.php#unique-entry-id-34</guid><content:encoded><![CDATA[Good data analysis consists of several important steps.<br />	<br /><ul class="disc"><li><em>Data editing</em> is when the researcher reviews the recorded data for accuracy, consistency and completeness</li><li>During<em> Data summarization</em>, the researcher summarizes the data. This consists of descriptive analysis such as tables that classify observations according to key factors</li><li>The last step is sometimes referred to as <em>estimation stage</em>. The researcher estimates the measures of occurrence or of effects, using confidence intervals. This final step involves interpreting the results. It also needs some consideration of factors that were not measured. <br /></li></ul>	<br /><p style="text-align:right;"><span style="font-size:10px; ">(Reference: Rothman KJ, Greenland S and Lash TL: 2008 Modern Epidemiology. Third Edition. Lippincott). </span><br /></p>]]></content:encoded></item><item><title>Data management</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2009-03-20T22:49:37+03:00</dc:date><link>http://thesis.uib.no/files/99f3860ca5803f757390e386503bc98a-30.php#unique-entry-id-30</link><guid isPermaLink="true">http://thesis.uib.no/files/99f3860ca5803f757390e386503bc98a-30.php#unique-entry-id-30</guid><content:encoded><![CDATA[<span style="font:13px Verdana, serif; color:#666666;">By data management, we mean how to prepare research data for analyses. <br /><br />It often consists of the following steps. First, we create a database, and enter the research data. When entering data, please remember:<br /></span><ol class="arabic-numbers"><li><span style="font:13px Verdana, serif; color:#666666;">Use number codes for categorical variables</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Choose suitable variable names, and label them to avoid confusion</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Check for double records, and for unlikely data values</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Make regular back-ups of the data set<br /></span></li></ol><span style="font:13px Verdana, serif; color:#666666;"><br />When analysing data, first remember to: <br /></span><ol class="arabic-numbers"><li><span style="font:13px Verdana, serif; color:#666666;">Do frequency analysis of all categorical variables</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Use box plots, histograms, and other tests to see if the continuous variables have a normal distribution</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Identify and deal with missing values</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Then redo the frequency and distribution checks<br /></span></li></ol><span style="font:13px Verdana, serif; color:#666666;"><br />It is important that you keep a logbook of the data management. Such a record should contain the following information:<br /></span><ol class="arabic-numbers"><li><span style="font:13px Verdana, serif; color:#666666;">Title of the proposed paper</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Author list, and identify who is responsible for data analysis and documentation</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Specific research questions to be answered</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Identify the outcome and explanatory variables to be used</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Statistical methods</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Information about the database location and file names</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Identify journals, and if suitable, scientific meetings, where you plan to present your results.<br /></span></li></ol><span style="font:13px Verdana, serif; color:#666666;"> <br />See also </span><span style="font:13px Verdana, serif; color:#666666;"><a href="http://thesis.uib.no/page3/page16/page16.php" rel="self" title="Statistical notes">Statistical notes</a></span>]]></content:encoded></item><item><title>Important reminder</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Guides</category><dc:date>2009-03-03T10:02:56+03:00</dc:date><link>http://thesis.uib.no/files/4d69fbb7919e83a861060a1fb5eeb296-29.php#unique-entry-id-29</link><guid isPermaLink="true">http://thesis.uib.no/files/4d69fbb7919e83a861060a1fb5eeb296-29.php#unique-entry-id-29</guid><content:encoded><![CDATA[Recently, Gavin Yamey, one of the <a href="http://medicine.plosjournals.org/perlserv/?request=index-html&issn=1549-1676" rel="self">Editors in PLoS Medicine</a> reported the journal PLoS Neglected Tropical Diseases editors rejected to review a clinical trial. They did not even send it for peer review, because the trial started after July 1 2005, and yet the authors had failed to prospectively register it in a clinical trials registry.<br /><br />Lesson: <a href="http://thesis.uib.no/files/cf99b4758fc45e7da8e1c106022daa4a-11.php" rel="self" title="Thesis writing blog:Reporting clinical trials">Register your trial in a clinical trials registry!</a>]]></content:encoded></item><item><title>Ten Simple Rules for Getting Published</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2009-03-11T09:46:14+03:00</dc:date><link>http://thesis.uib.no/files/758b9a0b8186b2c49d77c0c5a9513f44-28.php#unique-entry-id-28</link><guid isPermaLink="true">http://thesis.uib.no/files/758b9a0b8186b2c49d77c0c5a9513f44-28.php#unique-entry-id-28</guid><content:encoded><![CDATA[<span style="font:13px Verdana, serif; color:#666666;">Philip E. Bourne, the Editor in Chief of </span><span style="font:13px Verdana, serif; color:#666666;"><a href="http://www.ploscompbiol.org/home.action" rel="self">PLoS Computational Biology,</a></span><span style="font:13px Verdana, serif; color:#666666;"> recently wrote &ldquo;</span><span style="font:13px Verdana, serif; color:#3580F9;"><u><a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.0010057">Ten Simple Rules for Getting Published</a></u></span><span style="font:13px Verdana, serif; color:#666666;">&rdquo;: <br /></span><ul class="disc"><li><span style="font:13px Verdana, serif; color:#666666;">Rule 1: Read many papers, and learn from both the good and the bad work of others.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 2: The more objective you can be about your work, the better that work will ultimately become.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 3: Good editors and reviewers will be objective about your work.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 4: If you do not write well in the English language, take lessons early; it will be invaluable later.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 5: Learn to live with rejection.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 6: The ingredients of good science are obvious&mdash;novelty of research topic, comprehensive coverage of the relevant literature, good data, good analysis including strong statistical support, and a thought-provoking discussion.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 7: Start writing the paper the day you have the idea of what questions to pursue.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 8: Become a reviewer early in your career.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 9: Decide early on where to try to publish your paper.</span></li><li><span style="font:13px Verdana, serif; color:#666666;">Rule 10: Quality is everything.</span></li></ul>]]></content:encoded></item><item><title>Bias in scientific writing</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2009-03-02T08:51:34+03:00</dc:date><link>http://thesis.uib.no/files/5016069ed96ae124e809f74b7baec5ca-27.php#unique-entry-id-27</link><guid isPermaLink="true">http://thesis.uib.no/files/5016069ed96ae124e809f74b7baec5ca-27.php#unique-entry-id-27</guid><content:encoded><![CDATA[<a href="http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.1000038" rel="self">This month's PLoS Medicine editorial </a>discusses how various forms of bias and the effects of competing interests can influence scientific research. <br /><br />The article proposes five ways to reduce bias and the effects of competing interests: <br /><br /><ol class="arabic-numbers"><li>Recognize and declare editorial interests</li><li>Be aware of interests beyond the commercial: Most researchers are aware of the damaging nature of commercial competing interests. However, be also aware that your research can be influenced by the wish to promote an idea, or a research programme, rather than a commercial product. </li><li>Consider whether there is a ghost in the machine: Ghostwriting occurs when individuals who have made a large contribution to the research project, or to writing of the article, are not named as authors.  All authors should be named, and their names, and their roles and competing interests made clear in the publication.</li><li>Remember the protocol</li><li>Consider whether the data are important even if the results are not exciting</li></ol>]]></content:encoded></item><item><title>Research hierarchy?</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><category>Design</category><dc:date>2009-02-09T21:47:05+03:00</dc:date><link>http://thesis.uib.no/files/fc4a8fa72d4e0101d213bbf80ded71e0-21.php#unique-entry-id-21</link><guid isPermaLink="true">http://thesis.uib.no/files/fc4a8fa72d4e0101d213bbf80ded71e0-21.php#unique-entry-id-21</guid><content:encoded><![CDATA[<div class="image-right"><img class="imageStyle" alt="Bilde 2009-01-18 21-20-08" src="http://thesis.uib.no/files/bilde-2009-01-18-21-20-08.jpg" width="280" height="162"/></div>Two views exist of medical science: one underlines discovery and explanation, the other <a href="http://thesis.uib.no/files/727c6427ec62c6006ae3009675682371-18.php" rel="self" title="Thesis writing blog:Evaluating clinical studies">evaluation of interventions</a>. <br /><br />If the aim of the research is discovery and explanation, the following hierarchy shown in this figure may apply.<br /><br />A thorough discussion about this topic is presented by Vandenbroucke JP. Observational research, randomised trials, and two views of medical Science. PLoS Med 5(3): e67. doi:10.1371/journal pmed.0050067<br /><br />In an earlier blog entry, I wrote about two <a href="http://thesis.uib.no/files/f51e2e10d59cd9e8d5f5b3c0440a87a5-15.php" rel="self" title="Thesis writing blog:Understanding study design">research designs (types)</a>, experimental and descriptive. If the aim of the study is to evaluate interventions, most agree about the following hierarchy of study designs (<a href="http://thesis.uib.no/files/727c6427ec62c6006ae3009675682371-18.php" rel="self" title="Thesis writing blog:Evaluating clinical studies">see link</a>). ]]></content:encoded></item><item><title>Calculators for epidemiological statistics</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2009-01-25T13:24:06+03:00</dc:date><link>http://thesis.uib.no/files/92b0e011f81e3bd095f529642cadb801-20.php#unique-entry-id-20</link><guid isPermaLink="true">http://thesis.uib.no/files/92b0e011f81e3bd095f529642cadb801-20.php#unique-entry-id-20</guid><content:encoded><![CDATA[<span style="font:13px Verdana, serif; ">In the latest addition to </span><span style="font:13px Verdana, serif; "><a href="http://thesis.uib.no/page15/page15.php" rel="self" title="Research tools">Research tools</a></span><span style="font:13px Verdana, serif; ">, we refer to some </span><span style="font:13px Verdana, serif; "><a href="http://thesis.uib.no/page15/files/7193c7cb86b8817ba9e770dee4c7417b-2.php" rel="self" title="Research tools:Calculators for epidemiological statistics">Calculators for epidemiological statistics</a></span><span style="font:13px Verdana, serif; ">. </span>]]></content:encoded></item><item><title>Research tools</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2009-01-12T20:38:49+03:00</dc:date><link>http://thesis.uib.no/files/ab154fec6f2d4f2b508b317303a9eae6-19.php#unique-entry-id-19</link><guid isPermaLink="true">http://thesis.uib.no/files/ab154fec6f2d4f2b508b317303a9eae6-19.php#unique-entry-id-19</guid><content:encoded><![CDATA[This week we start presenting some <a href="http://thesis.uib.no/page15/page15.php" rel="self" title="Research tools">research tools</a> that PhD students need. I shall present topics as reference managers and different statistical software and tools. ]]></content:encoded></item><item><title>Evaluating clinical studies</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><category>Design</category><dc:date>2009-02-04T17:41:40+03:00</dc:date><link>http://thesis.uib.no/files/727c6427ec62c6006ae3009675682371-18.php#unique-entry-id-18</link><guid isPermaLink="true">http://thesis.uib.no/files/727c6427ec62c6006ae3009675682371-18.php#unique-entry-id-18</guid><content:encoded><![CDATA[How should we best be able to establish scientific knowledge? This question is often raised when evaluating therapeutic interventions. During the last 30 years, researchers and policy makers set up several levels or hierarchies of evidence. <br /><br /><div class="image-left"><img class="imageStyle" alt="Bilde 2009-01-18 21-25-41" src="http://thesis.uib.no/files/bilde-2009-01-18-21-25-41.jpg" width="311" height="376"/></div>Such levels (se figure) puts randomized controlled trials (RCT) at the top (best evidence), and observational studies (cohort, case-control and cross-sectional studies) at the bottom. Therefore, conventional wisdom is that to evaluate interventions, the RCT is the most appropriate research design. (See also <a href="http://thesis.uib.no/page5/page11/page11.html" rel="self" title="Guidelines">CONSORT</a> statement).<br /><br />The figure (from US Preventive Services Task Force. Guide to clinical preventive services, 2nd edn. Baltimore, MD: Williams & Wilkins, 1996) presents  how a researcher should rate clinical evidence. It is widely used as a design hierarchy when  assessing clinical interventions.<br /><br />However, as we shall discuss in the next blog entries, the <a href="http://thesis.uib.no/files/f51e2e10d59cd9e8d5f5b3c0440a87a5-15.php" rel="self" title="Thesis writing blog:Understanding study design">research design</a> depends on which question you ask. Are you comparing two or more treatments, or do you aim to discover the cause of a disease, or to find side effects of drugs? Such questions may demand different research designs.  ]]></content:encoded></item><item><title>The Vancouver Statement</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Guides</category><dc:date>2009-01-06T21:54:59+03:00</dc:date><link>http://thesis.uib.no/files/e94548743db976426e19c9fc72d04097-16.php#unique-entry-id-16</link><guid isPermaLink="true">http://thesis.uib.no/files/e94548743db976426e19c9fc72d04097-16.php#unique-entry-id-16</guid><content:encoded><![CDATA[The name of <a href="http://www.icmje.org/" rel="external">The Vancouver Guidelines </a>is &ldquo;Uniform Requirements for Manuscripts Submitted to Biomedical Journals: Writing and Editing for Biomedical Publication&rdquo;. A group of editors of medical journals made these guidelines some years ago. Most medical journals use them. <br /><br />The Uniform Requirements helps you to write accurate, clear, easily accessible reports of biomedical studies. The guidelines address the technical issues of preparing and submitting manuscripts. <br /><br />The Uniform Requirements state the ethical principles in the conduct and reporting of research, and provide recommendations about editing and writing. <br /><br />You will find it helpful to follow the recommendations because by doing so you improve the quality and clarity of manuscripts. <br /><br />Authors also need to become familiar with the Instructions to Authors specific to the journal you choose for the manuscript. <br /><br />Other  Guidelines<br /><br /><a href="http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371%2Fjournal.pmed.0040297" rel="external">The STROBE Guidelines</a><br /><br /><a href="http://www.consort-statement.org/" rel="external">The CONSORT Guildelines</a>]]></content:encoded></item><item><title>Understanding study design</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><category>Design</category><dc:date>2009-01-17T21:27:36+03:00</dc:date><link>http://thesis.uib.no/files/f51e2e10d59cd9e8d5f5b3c0440a87a5-15.php#unique-entry-id-15</link><guid isPermaLink="true">http://thesis.uib.no/files/f51e2e10d59cd9e8d5f5b3c0440a87a5-15.php#unique-entry-id-15</guid><content:encoded><![CDATA[<div class="image-left"><img class="imageStyle" alt="research design_2" src="http://thesis.uib.no/files/research-design_2.jpg" width="284" height="394"/></div><a href="http://thesis.uib.no/page3/page14/files/2431b0f208f6c0e20218642ef1837816-0.php" rel="self" title="Methods:Research design: an overview">It is important that researchers understand what studies</a> they do. And, when doing research, it is important that you describe which design you use. <br /><br />There are two types of clinical and epidemiological research: experimental and observational studies. If the investigator assigns the exposure, it is an experimental study. If the researcher does not assign the exposure, it is an observational study. (The figure on the left is copied from <span style="font:12px Trebuchet, Verdana, serif; ">Grimes DA, Schulz KF. An overview of clinical research: the lay of the land. </span><span style="font:12px Trebuchet, Verdana, serif; "><em>Lancet </em></span><span style="font:12px Trebuchet, Verdana, serif; ">2002;359:57-61).</span> <br /><br />We group experimental trials into randomised and non-randomised trials. <br /><br />Observational studies can be analytical or descriptive. Analytical studies use a comparison (control) group, whereas descriptive studies do not. <br /><br />Types of analytical studies include:<br /><ul class="disc"><li>Cohort studies track people forward in time from exposure to outcome. </li><li>Case-control studies work in reverse, tracing back from outcome to exposure. </li><li>Cross-sectional studies measures both exposure and outcome at one time point. <br /></li></ul><br />As descriptive studies, such as case-reports do not have a comparison group, investigators cannot examine associations. ]]></content:encoded></item><item><title>CONSORT Statement</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><category>Guides</category><dc:date>2008-12-26T21:08:49+03:00</dc:date><link>http://thesis.uib.no/files/bbc6bbfe1e950958c1d0b1fcf289aed9-14.php#unique-entry-id-14</link><guid isPermaLink="true">http://thesis.uib.no/files/bbc6bbfe1e950958c1d0b1fcf289aed9-14.php#unique-entry-id-14</guid><content:encoded><![CDATA[If you wish to publish a randomized controlled trial (RCT), you need to use the CONSORT Statement. It is backed by prominent general medical journals. In addition, these same journals demand that you register the trial before publication. <br /><br />CONSORT stands for Consolidated Standards of Reporting Trials. The main document is the CONSORT Statement, which is an evidence-based, minimum set of recommendations for reporting RCTs. It offers a standard way to prepare reports of trial findings. <br /><br />The CONSORT Statement contains a checklist of 22 items, and a flow diagram. The checklist items focus on how the trial was designed, analysed, and interpreted. The flow diagram displays the progress of all participants through the trial. <br /><br />Other Guidelines<br /><a href="http://www.icmje.org/" rel="external">The Vancouver Guidelines</a><br /><br /><a href="http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371%2Fjournal.pmed.0040297" rel="external">The STROBE Guidelines</a><br />]]></content:encoded></item><item><title>STROBE Statement</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><category>Guides</category><dc:date>2008-12-19T20:44:10+03:00</dc:date><link>http://thesis.uib.no/files/5db74d6ebd60d2b5d46b8724c4f28338-13.php#unique-entry-id-13</link><guid isPermaLink="true">http://thesis.uib.no/files/5db74d6ebd60d2b5d46b8724c4f28338-13.php#unique-entry-id-13</guid><content:encoded><![CDATA[Most of clinical and epidemiological research is observational. This includes cohort, case-control and cross-sectional studies. <br /><br />Reporting such research is often inadequate, and it makes it difficult for the reader to assess the strengths and weaknesses and of a study&rsquo;s generalisability. <br /><br /><a href="http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371%2Fjournal.pmed.0040297" rel="external">The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative</a> recommends what should be included in an observational study. It consists of 22 items on the title, abstract, introduction, methods, results, and discussion sections of articles. 18 items are common to all three study designs, and four are specific for cohort, case-control, or cross-sectional studies. <br /><br />You can find the STROBE statement here. <br /><a href="http://thesis.uib.no/files/page1_blog_entry13_1.pdf">STROBE Guildeines</a><br /><br />I suggest that you use the STROBE checklist when you write articles on your observational studies. <br /><br />Similar Guidelines (<a href="http://www.consort-statement.org/" rel="external">CONSORT</a>) exsist for clinical and field trials.<br /><br />Other Guidelines<br /><br /><a href="http://www.icmje.org/" rel="external">The Vancouver Guidelines</a><br /><br />]]></content:encoded></item><item><title>Reporting clinical trials</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2009-01-07T21:58:29+03:00</dc:date><link>http://thesis.uib.no/files/cf99b4758fc45e7da8e1c106022daa4a-11.php#unique-entry-id-11</link><guid isPermaLink="true">http://thesis.uib.no/files/cf99b4758fc45e7da8e1c106022daa4a-11.php#unique-entry-id-11</guid><content:encoded><![CDATA[Journals now demand that you report the Clinical Trials number when submitting the paper. Please see <a href="http://content.nejm.org/cgi/content/full/NEJMe048225" rel="external">Clinical Trial Registration: A Statement from the International Committee of Medical Journal Editors</a> for more information. <br /><br />Therefore, remember two things when reporting a clinical or field trial:<br /><ul class="disc"><li>Register the trial before you start the clinical or field trial. Information on how to register a trial is found <a href="http://www.who.int/ictrp/en/" rel="external">here</a>. </li><li>Use the <a href="page5/page11/page11.html" rel="self" title="Guidelines">CONSORT Guidelines</a> and the Flow diagram<br /></li></ul><br />These requirements are not only for drug trials, but also for other types of interventions. For example, trying new a new intervention such as active versus passive case finding in tuberculosis control.]]></content:encoded></item><item><title>Gateway Global Health</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2008-11-29T21:45:28+03:00</dc:date><link>http://thesis.uib.no/files/7d384c5ddd70b79bfaf32573f862b11c-9.php#unique-entry-id-9</link><guid isPermaLink="true">http://thesis.uib.no/files/7d384c5ddd70b79bfaf32573f862b11c-9.php#unique-entry-id-9</guid><content:encoded><![CDATA[<a href="http://www.biomedcentral.com/" rel="self"><img class="imageStyle" alt="headsquare" src="http://thesis.uib.no/files/page1_blog_entry9_1.jpg" width="260" height="60"/></a><br /><br /><span style="font:13px Verdana, serif; ">If you visit the site </span><span style="font:13px Verdana, serif; "><a href="http://www.biomedcentral.com/gateways/globalhealth" rel="external">Gateway Global Health</a></span><span style="font:13px Verdana, serif; "> at BioMedCentral (BMC) you will find a collection of journal at  BMC that dealts with global health or international health. </span>]]></content:encoded></item><item><title>Discussion: a good example</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Discussion</category><dc:date>2008-12-12T21:21:32+03:00</dc:date><link>http://thesis.uib.no/files/286db075e250e83856b67f7d23806d21-8.php#unique-entry-id-8</link><guid isPermaLink="true">http://thesis.uib.no/files/286db075e250e83856b67f7d23806d21-8.php#unique-entry-id-8</guid><content:encoded><![CDATA[<p>During the past weeks we have discussed the &ldquo;Discussion&rdquo; of a Thesis, or of a  scientific article. 	Please read the following article from <a href="http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(08)61483-X/fulltext" rel="external">The Lancet, 2008, 372; 1151 - 1162</a> to see how the authors in details discuss the methods they use. Even if they have described this in detail in their methods, they analyse the validity of their results. </p>]]></content:encoded></item><item><title>Discussion: in an article</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Discussion</category><dc:date>2008-11-29T20:32:00+03:00</dc:date><link>http://thesis.uib.no/files/f58d3c2223e17affbb63796ab140ddc5-7.php#unique-entry-id-7</link><guid isPermaLink="true">http://thesis.uib.no/files/f58d3c2223e17affbb63796ab140ddc5-7.php#unique-entry-id-7</guid><content:encoded><![CDATA[The <a href="http://thesis.uib.no/page3/page2/files/2021e8c0544826a94a2c0634817512d1-1.html" rel="self" title="Discussing methods:Discussion (scientific article)">discussion</a> is an exercise in logic and discipline. Usually is has the following parts:<br /><ol class="arabic-numbers"><li>It should state the main findings of the study in one or two sentences</li><li>The discussion should consider the methods, and address possible shortcomings</li><li>It should compare the results with other published findings</li><li>It should discuss the implications of the results. Sometimes you need to answer the questions &laquo;What does this mean for practice of policy&raquo; and &laquo;Are there any needs for further studies&raquo;.<br /></li></ol>]]></content:encoded></item><item><title>Discussion: in a Thesis</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Discussion</category><dc:date>2008-11-22T09:22:00+03:00</dc:date><link>http://thesis.uib.no/files/81bdaf22f8e0484a3daee5718e17c4e6-6.php#unique-entry-id-6</link><guid isPermaLink="true">http://thesis.uib.no/files/81bdaf22f8e0484a3daee5718e17c4e6-6.php#unique-entry-id-6</guid><content:encoded><![CDATA[One of the expected learning outcomes of a PhD work is &ldquo;The ability to critically analyse and evaluate one&rsquo;s findings and those of others&rdquo;. This is often done under the Literature review, and under Discussion. <br /><br />The overall view of epidemiologic studies can be seen as accuracy in estimation. Therefore, a PhD thesis should critically address the process that leads to an estimate (result). In addition to discussing the main results, validity should be addressed. <br /><br />In your thesis, use some pages to discuss the validity (are the results believable, credible, or sound?).  You need to systematically adress both <em>internal</em> and <em>external</em> validity. For more details on how to structure the Methodological considerations , please read more <a href="http://thesis.uib.no/page3/page2/page2.html" rel="self" title="The Discussion: Validity">here</a>. <br /><br />Next week we shall present some thoughts about the Discussion in a scientific article. <br />]]></content:encoded></item><item><title>&#x22;Statistically significant&#x22; or &#x22;Statistically detectable&#x22;?</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2008-11-16T07:54:33+03:00</dc:date><link>http://thesis.uib.no/files/7bc7eee247c113da4d428a7e731dd6d5-5.php#unique-entry-id-5</link><guid isPermaLink="true">http://thesis.uib.no/files/7bc7eee247c113da4d428a7e731dd6d5-5.php#unique-entry-id-5</guid><content:encoded><![CDATA[<a href="http://www.nature.com/nature/journal/v455/n7216/index.html" rel="external">The October 24 (2008) issue of </a><em><a href="http://www.nature.com/nature/journal/v455/n7216/index.html" rel="external">Nature</a></em><a href="http://www.nature.com/nature/journal/v455/n7216/index.html" rel="external">,</a> contains an interesting discussion about "<a href="http://www.nature.com/news/2008/081022/full/4551023a.html" rel="external">Disputed Definitions</a>". The words statistical significance is often misused and misunderstood by researchers and research students. <br /><br />I have copied the<a href="http://thesis.uib.no/URL" rel="external"> </a>Nature text.The author is Geoff Brumfiel.  <br /><br /><div class="image-left"><img class="imageStyle" alt="4551023a-i12.0" src="http://thesis.uib.no/files/page1_blog_entry5_1.jpg" width="240" height="114"/></div><em>" Few words in the scientific lexicon are as confusing, or as loaded, as 'significant'. Statisticians wring their hands over its cavalier use to describe scientific validity. And backed by statistics or not, researchers commonly employ the word to illustrate the importance of their latest finding.<br /><br />The very definition of statistical significance is misunderstood by most scientists, says Steven Goodman, a biostatistician at the Johns Hopkins School of Medicine in Baltimore, Maryland, and associate editor on Annals of Internal Medicine. Typically, researchers take a result to be statistically significant based on 'p-values'. This parameter is used, for example, to reveal whether a drug lowers cholesterol based on promising data collected in a clinical trial.<br /><br />According to the common interpretation, a 'significant' result with a p-value of 0.05 or less means that there is a 5% or less chance that the drug is ineffective. According to the statistically accurate definition, there is a 5% or less chance of seeing the observed data even though the drug is, indeed, ineffective. Rhetorically, the difference may seem imperceptible; mathematically, say statisticians, it is crucial. In situations in which the data is somewhat ambiguous, there is a chance that results can be misinterpreted. "It's diabolically tricky," Goodman says.<br /><br />Most statisticians resign themselves to abuse of the term's strict definition. But more grievous trespasses abound. "Statistical significance is neither a necessary nor a sufficient condition for proving a scientific result," says Stephen Ziliak, an economist at Roosevelt University in Chicago, Illinois, and co-author of The Cult of Statistical Significance. P-values are often used to emphasize the certainty of data, but they are only a passive read-out of a statistical test and do not take into account how well an experiment was designed. A p-value would not reveal, for example, that everyone was taking different doses of that cholesterol drug. In many experiments, Ziliak says, "there are so many different errors that they tend to swamp the p-value errors".<br /><br />Even if a result is a genuinely statistically significant one, it can be virtually meaningless in the real world. A new cancer treatment may 'significantly' extend life by a month, but many terminally ill patients would not consider that outcome significant. A scientific finding may be 'significant' without having any major impact on a field; conversely, the significance of a discovery might not become apparent until years after it is made. "One has to reserve for history the judgement of whether something is significant with a capital S," says Steven Block, a biophysicist at Stanford University in California.<br /><br />In some situations other statistical methods can substitute, but Goodman believes that trying to use them in the scientific literature would be like "talking Swahili in Louisiana". He says he and other editors do their best to keep the term out of Annals though. "We ask them to use words like 'statistically detectable' or 'statistically discernable,'" he says".</em><br />]]></content:encoded></item><item><title>Thesis writing</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2008-11-14T22:05:37+03:00</dc:date><link>http://thesis.uib.no/files/bbccb6ddd62afb025090b32fa39bab6d-4.php#unique-entry-id-4</link><guid isPermaLink="true">http://thesis.uib.no/files/bbccb6ddd62afb025090b32fa39bab6d-4.php#unique-entry-id-4</guid><content:encoded><![CDATA[<span style="font-size:14px; color:#444444;">Writing your </span><span style="font-size:14px; color:#444444;"><a href="http://thesis.uib.no/page3/page7/page7.html" rel="self" title="PhD structure at the UoB">PhD dissertation</a></span><span style="font-size:14px; color:#444444;"> is an exciting time in your life.  After all, once you get your PhD, you will be called &ldquo;Doctor So-and-So,&rdquo; and you are recognized as someone who makes a serious contribution to your field of study.  Many, doors open to you, and some get the possibility to obtain a tenure track (permanent employment) teaching and research job at a college or university.  <br /><br />What is a PhD thesis all about? The dissertation should be the thorough result of your original research. At UoB, the research papers are the most important part of the PhD &ndash; or Doctor of Philosophy &ndash; degree. And, the research should be original and thought-provoking.  <br /><br />The thesis contains </span><span style="font-size:14px; color:#444444;"><a href="http://thesis.uib.no/page3/page3.html" rel="self" title="Main parts of PhD thesis">several chapters</a></span><span style="font-size:14px; color:#444444;">.  The main differences between, a PhD dissertation and a Master dissertation are the degree you are trying to obtain and the length.  The PhD dissertation is much more thorough and in detail than other dissertations.</span><span style="font:13px Arial, Verdana, Helvetica, sans-serif; color:#444444;"><br /></span>]]></content:encoded></item><item><title>Statistical notes</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Methods</category><dc:date>2008-06-30T22:40:00+03:00</dc:date><link>http://thesis.uib.no/files/366c44c880aea2c7ec77052729b55fb5-3.php#unique-entry-id-3</link><guid isPermaLink="true">http://thesis.uib.no/files/366c44c880aea2c7ec77052729b55fb5-3.php#unique-entry-id-3</guid><content:encoded><![CDATA[<span style="font:14px Verdana, serif; ">In this </span><span style="font:14px Verdana, serif; "><a href="http://thesis.uib.no/page3/page16/page16.php" rel="self" title="Statistical notes">section</a></span><span style="font:14px Verdana, serif; "> we shall discuss some statistical questions that we often see when writing a paper. <br /><br />For example one recent reviewer of a paper wrote: &ldquo;In the results section, it is not necessary to give the 95%CI (Confidence Intervals) and the p value. Since the p value is given in the tables, the 95%CI is enough in the text.&rdquo;<br /><br />It is usually unnecessary to report both P values and 95% CI. We use P values for hypothesis testing, and 95% CI for estimation. The latter provides more information. Please see Gardner and Altman&rsquo;s </span><span style="font:14px Verdana, serif; "><a href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=3082422" rel="external">discussion</a></span><span style="font:14px Verdana, serif; ">. <br /><br />Here is a good web site on medical statistics:<br />Martin Bland has written several books on statistics and also many short articles in the BMJ on different statistics issues. They are all freely available on </span><span style="font:14px Verdana, serif; "><a href="http://www-users.york.ac.uk/~mb55/pubs/jmbpb.htm" rel="external">his web site</a></span><span style="font:14px Verdana, serif; ">. <br /></span>]]></content:encoded></item><item><title>Literature review</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Introduction</category><dc:date>2008-05-29T23:28:14+03:00</dc:date><link>http://thesis.uib.no/files/573d77336cb3eb1935060caedec8d17f-2.php#unique-entry-id-2</link><guid isPermaLink="true">http://thesis.uib.no/files/573d77336cb3eb1935060caedec8d17f-2.php#unique-entry-id-2</guid><content:encoded><![CDATA[<span style="font:14px Verdana, serif; ">A literature review offers an overview of the relevant and important literature on a research area. It reviews the important points of current knowledge on your PhD topic. Most often, the review is a survey of articles, books, conference papers and theses. <br /><br />Often, the review is limited to a particular timeframe. It should include a description, summary, and critical evaluation of the materials presented. Thus, a literature review is not a list describing or summarising one piece of literature after another.<br /><br />The purpose of a literature review is to show your ability to identify the relevant information and outline existing knowledge. The literature review shall identify the "gaps" in the research that your work will address, and produce a reason (or justification) for your study.<br /><br />See </span><span style="font:14px Verdana, serif; "><a href="http://thesis.uib.no/page3/page8/page8.html" rel="self" title="Literature review">Litterature review</a></span><span style="font:14px Verdana, serif; "> for more... <br /></span>]]></content:encoded></item><item><title>Some information about the web page</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><dc:subject>Thesis writing blog</dc:subject><dc:date>2008-05-21T17:33:00+03:00</dc:date><link>http://thesis.uib.no/files/4ff9ea26707d9bd1a9732f39977792b7-0.php#unique-entry-id-0</link><guid isPermaLink="true">http://thesis.uib.no/files/4ff9ea26707d9bd1a9732f39977792b7-0.php#unique-entry-id-0</guid><content:encoded><![CDATA[<span style="font-size:14px; ">I have started to make a web page that would help PhD students in writing their PhD thesis. I hope we may together make a web-page where you may find useful information.<br /><br />I also think it should be a place where we could discuss important topics relevant for the PhD thesis.<br /><br />I have just started writing the web page. Please send your comment on issues you think we should include in this web page.</span><span style="font:16px Verdana, serif; "><br /></span>]]></content:encoded></item><item><title>Some more rules when reporting numbers:</title><dc:creator>bernt.lindtjorn@cih.uib.no</dc:creator><category>Publishing</category><dc:date>2009-04-21T14:53:55+03:00</dc:date><link>http://thesis.uib.no/files/8515586b2810429748bf8ed6cbe98da0-36.php#unique-entry-id-36</link><guid isPermaLink="true">http://thesis.uib.no/files/8515586b2810429748bf8ed6cbe98da0-36.php#unique-entry-id-36</guid><content:encoded><![CDATA[There are some general rules on how to report epidemiological and statistical results. Some of these rules are:<br /><ul class="disc"><li>Report percentages to only one decimal point if the sample size is larger than 100</li><li>Report percentages with no decimal point if the sample size is less than 100</li><li>Do not use percentages if the sample size is less that 20 (In the sample of 14 children, 3 were malnourished)</li><li>For ranges use "to" or comma, but not "-". This to avoid confusion with the minus sign. remember to use the same number of decimal places as the summary statistics. (The mean height was 176 cm (95% CI 172 to 180) or The mean height was 176 cm (95% CI 172, 180).  </li></ul>]]></content:encoded></item></channel>
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