Background: The efficacy of specific interventions also of mind-body medicine is also dependent on the patients' ability to engage in these interventions and to perceive and change health-affecting attitudes and behaviors. The aim was to validate a 13-item instrument to measure (1) the patients' perception of specific attitudes and behaviors that are assumed to have a negative influence on the health situation, (2) their intention to change them, and (3) the implementation of the intended changes in their life affairs. Patients and Methods: Anonymous cross-sectional survey among 512 patients with chronic pain conditions (mean age 42.6 ± 11.4 years; 58% women) using standardized instruments. Results: After the elimination of 4 items, an explorative factor analysis of the 9 remaining items indicated 2 factors that would explain 57% of the variance: Perceptions/Intentions (5 items; Cronbach's alpha = 0.75) and Ability/ Implementation (4 items; alpha = 0.77). Factor 2 correlated moderately to strongly with internal adaptive coping strategies (AKU) and situational awareness (CPSC), and weakly with mental health (SF-36), life satisfaction (BMLSS), and low depressive symptoms (BDI) and escape from illness (Escape). Factor 1 correlated weakly with age and adaptive coping strategies (AKU). Conclusions: The final 9-item Perception, Intention and Ability to Change (PIAC) scale was approved as a short, practicable and promising instrument, which should be further evaluated in the context of training and intervention programs, particularly with respect to its predictive relevance.