Translation and Cross-Cultural Adaptation with Preliminary Validation of GCOS-24 for Use in Spain

The aim in this study was to translate and cross-culturally adapt the Genetic Counseling Outcome Scale (GCOS-24) for use in Spain and to carry out a preliminary psychometric validation in a sample of Spanish patients. With oversight by an expert panel, forward and backward translations were conducted to create the draft Spanish GCOS-24. Fourteen patients were recruited from a clinical genetics service in Madrid, Spain, to participate in cognitive interviews designed to explore readability and interpretability of the draft. Following qualitative analysis of interview transcripts, a final version of the Spanish GCOS-24 was agreed with the expert panel. No significant cross-cultural differences were identified. The Spanish GCOS-24 was then completed prior to and 2–4 weeks after genetic counseling by 59 patients attending the service, and data were analysed using analysis of variance. Preliminary psychometric validation of the Spanish GCOS-24 showed significantly higher GCOS-24 scores after genetic counseling (p < 0.0001), with good internal consistency (α = 0.84) and sensitivity to change over time, with a medium-to-large size effect (Cohen’s d = 0.70). This compares well with the original English language GCOS-24. Findings demonstrate that the Spanish GCOS-24 has potential for use in evaluating clinical genetics services in Spain, but would benefit from assessment of test-retest reliability as well as structural and construct validity.