The development of the Clinician-reported Genetic testing Utility InDEx (C-GUIDE): a novel strategy for measuring the clinical utility of genetic testing

Abstract

PurposeClinical utility describes a genetic test’s value to patients, families, health-care providers, systems, or society. This study aims to define clinical utility from the perspective of clinicians and develop a novel outcome measure that operationalizes this concept. MethodsItem selection for the Clinician-reported Genetic testing Utility InDEx (C-GUIDE) was informed by a scoping review of the literature. Item reduction was guided by qualitative and quantitative feedback from semistructured interviews and a cross-sectional survey of genetics and nongenetics specialists. Final item selection, index scoring, and structure were guided by feedback from an expert panel of genetics professionals. ResultsA review of 194 publications informed the selection of a preliminary set of 25 items. Feedback from 35 semistructured interviews, 113 surveys, and 11 expert panelists informed the content and wording of C-GUIDE’s final set of 18 items that reflect on the utility of testing related to diagnosis, management, and familial/psychosocial impact. C-GUIDE achieves content and face validity for use in a range of diagnostic genetic testing settings. ConclusionWork to establish reliability and construct validity is underway. C-GUIDE will be useful in comparative studies to generate policy-relevant evidence pertaining to the clinical utility of genetic testing across a range of settings.