Measures repetitive passive focus on distress and its causes. Brooding (passive comparison with unachieved standards) is maladaptive and specifically predicts depressive episodes. Reflection (purposeful inward turning) is less maladaptive. Central to Response Styles Theory.
Nolen-Hoeksema, S., & Morrow, J. (1991). A prospective study of depression and posttraumatic stress symptoms after a natural disaster. Journal of Personality and Social Psychology, 61(1), 115–121.
Free access to 2023+ psychometric scales at PsychScales