BACKGROUND: With the increased use of patient-reported outcomes measures (PROMs) to assess spine surgery outcomes, it is important to understand how patients interpret their health changes over time. The measurement of cognitive-appraisal processes enables the quantification of how individuals think about quality of life (QOL). This study examined how appraisal processes were associated with patients' views of their role in managing their health-patient activation. METHODS: This longitudinal cohort study from August 2019 to January 2022 included 222 adults undergoing spine surgery for cervical (n = 107) and/or lumbar (n = 148) pathology at an academic medical center. PROMs assessed disability (Neck Disability Index for cervical or Oswestry Disability Index for lumbar) and mental health (PROMIS-29 v2.0), cognitive-appraisal processes (QOLAP-SF), and patient activation (Patient Activation Measure). ANOVA models were used to examine the relationships between QOL and cognitive appraisal processes before and after surgery, overall and stratified by patient-activation stage. Effect sizes facilitated interpretation. RESULTS: There were significant improvements in pain-related disability and mental health following surgery. Cognitive appraisal processes explained substantial amounts of variance, particularly with changes in mental health (45% before surgery, 75% at three months, and 63%, at 12-months after surgery). With respect to physical disability, less disability was associated with a lesser focus on negative aspects of QOL. Appraisal explained the most variance before surgery for high-activation patients. At 12-months post-surgery, however, appraisal explained the most variance for the low-activation patients. Appraisal explained similar amounts of variance in mental health at baseline and three-months post-surgery for all activation groups, but substantially more variance in the low-activation group at 12-months post-surgery. There were differences in the direction of appraisal-outcome associations by activation group in selected appraisal items/domains. CONCLUSIONS: Cognitive-appraisal processes demonstrate a significant relationship with QOL among spine surgery patients. These processes explain substantial variance in pain-related disability and mental health, especially among those high in activation before surgery and those low in activation at 12-months post-surgery. Our findings suggest that patients' ways of thinking about their health may be effective targets of motivational coaching, to help them become more engaged over the recovery trajectory.