Two-pass verification

<h2 id="modern-use">Modern use</h2>
<p>While this method of quality control clearly is not proof against systematic errors or operator misread entries from a source document, it is very useful in catching and correcting random miskeyed strokes which occur even with experienced data entry operators. However, it proved to be a fatally tragic flaw in the <a href="/facts/Therac_25/9QNxTmtC">Therac 25</a> incident. This method has survived the keypunch and is available in some currently available data entry programs (e.g. <a href="/facts/PSPP/Nv5eIz4V">PSPP</a>/<a href="/facts/SPSS/6PGBVUXF">SPSS</a> Data Entry). One study suggests that, at least in simulated circumstances, a single-pass data entry with range checks and skip rules might not significantly alter the reliability of outcomes compared to studies using two-pass data entry;<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a> however, it is desirable to implement both systems in a data entry application.
</p>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>"Everything about punch cards". December 28, 2012. Retrieved June 20, 2013. <a href="https://www.museumwaalsdorp.nl/computer/en/punchcards.html" target="_blank">https://www.museumwaalsdorp.nl/computer/en/punchcards.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"IBM 129 Data Card Recorder" (PDF). Retrieved 2024-02-08. <a href="http://ed-thelen.org/comp-hist/IBM-ProdAnn/129.pdf" target="_blank">http://ed-thelen.org/comp-hist/IBM-ProdAnn/129.pdf</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Day, Simon (1998). "Double Data Entry: What Value, What Price?". Controlled Clinical Trials. 19 (1): 15–24. doi:10.1016/S0197-2456(97)00096-2. PMID 9492966. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
</ol>

Two-pass verification open-in-new

Two-pass verification