Adaptation and validation of a scale of self-efficacy and social support for physical activity in Spanish patients with severe mental disorders.

People with severe mental disorders (SMDs) suffer problems of obesity, a sedentary life, and poor physical condition, mainly due to low levels of physical activity. Self-efficacy (SE) and social support (SS) are important components that influence participation in physical activity. This study adapted a scale to assess SE and SS in promoting physical activity in Spanish people with SMDs, as well as provide preliminary evidence of its validity. One hundred Spanish patients (23% female) with SMDs, between 26 and 61 years old, completed the SE/SS assessment for SMD (SE/SS-ASMD). The instrument seemed to capture a four-factor structure in people with SMDs. Due to the lack of a gold standard, the scale was related to other instruments with which it might be expected to show a correlation, such as those for physical activity and its quality; however, the levels of correlation found were low (≈0.3). The Internal consistency (Cronbach's α) for the SE-ASMD, SS-ASMD staff, SS-ASMD peers, and SS-ASMD family scales were 0.76, 0.76, 0.80, and 0.80, respectively. The psychometric analysis of the SE/SS-ASMD supported its suitability as a new tool for researchers in the area of physical activity among people with SMDs