Recent work on patient-reported outcomes (PROs) focuses on precise, brief measures, which generally convey little about what an individual's rating actually means. Individual differences in appraisal are important and relevant to PRO research. This paper highlights the advantages of integrating appraisal assessment into clinical research. The most comprehensive method for assessing appraisal, the quality of life (QOL) Appraisal Profile, includes open-ended and multiple choice questions to assess four appraisal parameters: frame of reference, sampling of experience, standards of comparison, and combinatory algorithm. We illustrate with empirical findings four classes of investigation that would benefit from appraisal assessment: methodological, interpretation of change, the backstory of resilience, and clinical applications. A methodological investigation of HIV/AIDS patients revealed a range of cognitive schemas induced by the then-test response shift detection method, only 15% of which reflected the presumed process invoked. In this same study and in a study of people with multiple sclerosis (MS), interpretation of change in positive versus negative mental-health response shifts was characterized by different appraisal processes. In studying resilience in MS patients, patients with more reserve-building activities were more likely to use appraisals that emphasized the positive and more controllable aspects of their illness experience, as compared to lower-reserve patients. In underserved cancer patients, the QOL Appraisal Profile was used as a clinical interview to articulate current concerns and for personalized treatment decision-making to reduce burden and promote adherence. Integrating appraisal assessment can provide a more textured, person-centered understanding of person-factors not captured by standard PROs.