Validity in research refers to how accurately a study answers the study question or the strength of the study conclusions. For outcome measures such as surveys or tests, validity refers to the accuracy of measurement. Here validity refers to how well the assessment tool actually measures the underlying outcome of interest. Validity is not a property of the tool itself, but rather of the interpr...

Dear Editor: I write to congratulate Fisher et al for their work on the Eye Surgical Skills Assessment Test (ESSAT) for ophthalmology residency. The determination of the validity of tools for assessing resident competency is a crucial part of the Accreditation Council for Graduate Medical Education outcomes project over time. It might be worthwhile for the readership to understand how different...

This study examines whether making question formats better fit the cultural context of markets would improve the construct validity of estimates of willingness to pay (WTP). WTP for insecticide-treated mosquito nets was elicited using the bidding game, binary with follow-up (BWFU), and a novel structured haggling technique (SH) that mimicked price taking in market places in the study area. The ...

After publication of this article [1], concerns were raised about the validity of the study design and conclusions reported. Following a post-publication assessment involving staff editors and members of our Editorial Board, the PLOS ONE Editors decided to retract this article due to methodological concerns that call into question the validity of the study and its conclusions which the peer rev...

The ability to integrate theory with practice is integral to a student's success. A common reason for attrition from a nurse anesthesia program is clinical issues. To document clinical competence, students are evaluated using various tools. For use of a clinical evaluation tool as possible evidence for a student's dismissal, an important psychometric property to ensure is instrument validity. C...