Desarrollo de la versión española de la Escala Breve para la Evaluación de la Capacidad Funcional [Sp-UPSA-Brief] para pacientes con esquizofrenia y trastorno bipolar

Introduction In patients with severe mental disorders outcome measurement should include symptoms, cognition, functioning and quality of life at least. Shorter and efficient instruments have greater potential for pragmatic and valid clinical utility. Our aim was to develop the Spanish UPSA Brief scale (Sp-UPSA-Brief). Material and methods Naturalistic, 6-month follow-up, multicentre study. 139 patients with schizophrenia, 57 with bipolar disorder and 31 controls were evaluated using the Sp-UPSA, CGI-S, GAF, and PSP. We conducted a multivariate linear regression model to identify candidate subscales for the Sp-UPSA-Brief. Results The stepwise regression model for patients with schizophrenia showed that communication and transportation Sp-UPSA subscales entered first and second at p < 0.0001 (R² = 0.88, model df = 2, F = 395.05). In patients with bipolar disorder transportation and communication Sp-UPSA subscales entered first and second at p < 0.0001 (R² = 0.87, model df = 2, F = 132.32). Cronbach's alpha was 0.78 in schizophrenia and 0.64 in bipolar patients. Test-retest was 0.66 and 0.64 (p < 0.0001) respectively. Pearson correlation coefficients between Sp-UPSA and Sp-UPSA-Brief were 0.93 for schizophrenia and 0.92 for bipolar patients (p < 0.0001).The Sp-UPSA-Brief discriminated between patients and controls. In schizophrenia patients it also discriminated among different levels of illness severity according to CGI-S scores. Conclusion The Sp-UPSA-Brief is an alternate instrument to evaluate functional capacity that is valid and reliable. Having a shorter instrument makes it more feasible to assess functional capacity in patients with severe mental disorders, especially in everyday clinical practice.