<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>Hello,</div>
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<div>I have a problem to extract data from one study. I want to calculate hedges g. </div>
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<div>I have the following information (2 groups): </div>
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<div>Between-group change score from baseline to follow-up (9 months) is 1.8(-5.7,9.3) (mean and 95%CI) and p-value 0.64</div>
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<div>Sample size is n1 = 30; n2 = 36 (two group RCT).</div>
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<div>Link: <a href="https://linkinghub.elsevier.com/retrieve/pii/S1063458420309882">https://linkinghub.elsevier.com/retrieve/pii/S1063458420309882</a> (TABLE 2 HOOS ADL) </div>
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<div>I would do it the following way:</div>
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<div>Calculate a SD for both group from the CI. _> SE = (Upper limit-lower limit)/t-statistic (~2) => SD = SE/squ(1/n1 + 1/n2)</div>
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<div>Then g = d = MD/SD</div>
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<div>g* = (1-3/(4*(n1+n2)-9) * g</div>
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<div>e.g.</div>
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<div>SE = (9.3+5.7)/1.99 = 7.54 => SD = 7.54/squ(1/30+1/36) = 7.54/0.25 = 30.16</div>
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<div>g = 1.8/30.16 = 0.06</div>
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<div>g* = 0.06 * (1-3/255) = 0.06 * 0.99 = 0.0594</div>
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<div>Is that correct?</div>
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<div>Best regards</div>
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<div>Tobias</div></div></body></html>