Assessing sensitivity to change of the genomics outcome scale (GOS)

The Genetic Counseling Outcome Scale (GCOS-24) is a 24-item patient-reported outcome measure (PROM) that was developed to evaluate genetic counseling and testing services by measuring the construct of empowerment. The Genomics Outcome Scale (GOS) is a 6-item version of GCOS-24 that was designed to provide a PROM for use both within and outside clinical genetics services and reduce respondent burden. However, unlike GCOS-24, the sensitivity to change of the GOS has not yet been assessed in appropriate clinical settings. We carried out pre- and post-clinic surveys using the GOS to assess sensitivity to change of the GOS and produce before-and-after GOS data as part of a service evaluation. The survey was sent to patients attending the genetic counseling clinic for a first appointment at the All Wales Medical Genetic Service from 8 April 2019 to 18 September 2019. Patients attending disease management clinics, where genetic issues were not the primary concern, were excluded from this study. A total of 138 respondents were included in the final analysis. The result shows that empowerment scores, measured using the GOS, were significantly higher (p<0.05) after clinic attendance. The GOS shows good sensitivity to change, with a medium-to-large effect size (Cohen's d = 0.73). The result also shows that the service is delivering measurable benefits for its service users.