Spanish Adaptation and Validation of the Outcome Questionnaire OQ-30.2

This study assessed the psychometric properties of a Spanish version of the Shortened Outcome Questionnaire (OQ-30.2, Lambert et al., 2004) validated with a sample of 546 patients in an outpatient mental health clinic and 100 non-clinical adults in Chile. Our results show that this measure has similar normative data to the original measure, with a cutoff score for the Chilean population set at 43.36, and the reliable change index at 14. This Spanish OQ-30.2 has good internal consistency (α=0.90), has concurrent validity with the Depressive, Anxious, and Somatoform Disorders measuring scale (Alvarado, 1991), and is sensitive to change during psychotherapy. Consistent with previous studies, factorial analyses showed that both, the one- factor solution for a general scale and the three-factor solution containing three theoretical scales yielded poor fit estimates. Overall, our results are similar to past research on the OQ-45 and the OQ-30. The short version has adequate psychometric properties, comparable to those of the OQ-45, but provides a gain in application time that could be relevant in the setting of psychotherapy research with large samples, frequent assessments over time, and/or samples that may require more assistance completing items (e.g. low-literacy). We conclude that this measure will be a valuable instrument for research and clinical practice.