- Although women demonstrate higher levels of rumination than men, it is unknown whether instruments used to measure rumination have the same psychometric properties for women and men. To examine this question, we evaluated measurement invariance of the brooding and reflection subscales from the Ruminative Responses Scale (RRS) by gender, using data from four samples of undergraduates from three universities within the United States ( N = 4,205). A multigroup confirmatory factor analysis revealed evidence for configural, metric, and scalar invariance of the covariance structure of the 10-item version of the RRS. There were statistically significant latent mean differences between women and men, with women scoring significantly higher than men on both brooding and reflection. These findings suggest that the 10-item version of the RRS provides an assessment of rumination that is psychometrically equivalent across gender. Consequently, gender differences in brooding and reflection likely reflect valid differences between women and men.