Dynamic Imaging Grade of Swallowing Toxicity (DIGEST): Scale development and validation : Dynamic Imaging Grade of Swallowing Toxicity

Abstract

<div class="section"> <a class="named-anchor" id="S1"> <!-- named anchor --> </a> <h5 class="section-title" id="d372911e318">Purpose</h5> <p id="P1">NCI’s Common Terminology Criteria for Adverse Events (CTCAE) is the universal framework for toxicity reporting in oncology trials. We sought to develop a CTCAE-compatible modified barium swallow (MBS) grade for the purpose of grading pharyngeal dysphagia as a toxicity endpoint in cooperative group organ preservation trials for head and neck cancer (HNC). We hypothesized that a 5-point CTCAE-compatible MBS grade (“DIGEST”) based on the interaction of pharyngeal residue and laryngeal penetration/aspiration ratings is feasible and psychometrically sound. </p> </div><div class="section"> <a class="named-anchor" id="S2"> <!-- named anchor --> </a> <h5 class="section-title" id="d372911e323">Methods</h5> <p id="P2">A modified Delphi exercise was conducted for content validation, expert consensus, and operationalization of DIGEST criteria. Two blinded raters scored 100 MBS conducted before or after surgical or non-surgical organ preservation. Intra- and inter-rater reliability were tested by weighted <i>Kappa</i>. Criterion validity against OPSE, MBSImP™©, MDADI, and PSS-HN was assessed with one-way ANOVA and <i>post hoc</i> pairwise comparisons between DIGEST grades. </p> </div><div class="section"> <a class="named-anchor" id="S3"> <!-- named anchor --> </a> <h5 class="section-title" id="d372911e334">Results</h5> <p id="P3">Intra-rater reliability was excellent (weighted <i>Kappa</i>=0.82–0.84) with substantial to almost perfect agreement between raters (weighted <i>Kappa</i>=0.67–0.81). DIGEST significantly discriminated levels of pharyngeal pathophysiology (MBSImP™©: r=0.77, p&lt;0.0001), swallow efficiency (OPSE: r=−0.56, p&lt;0.0001), perceived dysphagia (MDADI: r=−0.41, p&lt;0.0001), and oral intake (PSS-HN diet: r=−0.49, p&lt;0.0001). </p> </div><div class="section"> <a class="named-anchor" id="S4"> <!-- named anchor --> </a> <h5 class="section-title" id="d372911e345">Conclusions</h5> <p id="P4">With the development of DIGEST, we have adapted MBS rating to the CTCAE nomenclature of ordinal toxicity grading used in oncology trials. DIGEST offers a psychometrically sound measure for HNC clinical trials and investigations of toxicity profiles, dose-response, and predictive modeling. </p> </div>