CONTEXT: Monitoring of health-related quality of life (HRQOL) and symptoms of patients with brain tumors is needed yet not always feasible. This is partially due to lack of brief-yet-precise assessments with minimal administration burden that are easily incorporated into clinics. Dynamic computerized adaptive testing (CAT) or static fixed-length short-forms, derived from psychometrically-sound item banks, are designed to fill this void. OBJECTIVE: This study evaluated the comparability of scores obtained from CATs and short-forms. METHODS: Patients (ages 7-22) were recruited from brain tumor clinics and completed PROMIS CATs and short-forms (Fatigue, Mobility, Upper Extremity, Depressive Symptoms, Anxiety, and Peer Relationships). Pearson correlations, paired t-tests, and Cohen's d were used to evaluate the relationship, significant differences and the magnitude of the difference between these two scores, respectively. RESULTS: Data from 161 patients with brain tumors were analyzed. Patients completed each CAT within 2 minutes. Scores obtained from CATs and short-forms were highly correlated (r=0.95 - 0.98). Significantly different CAT versus short-form scores were found on 4 (of 6) domains yet with negligible effect sizes (|d| < 0.09). These relationships varied across patients with different levels of reported symptoms, with the strongest association at the worst or best symptom scores. CONCLUSIONS: This study demonstrated the comparability of scores from CATs and short-forms. Yet the agreement between these two varied across degrees of symptom severity which was a result of the ceiling effects of static short-forms. We recommend CATs to enable individualized assessment for longitudinal monitoring.