<![CDATA[Prolonged waiting times are particularly burdensome in oncology clinics, where patients require repeated and complex visits. The previous web-based registration system at Dr. Kariadi General Hospital did not provide real-time queue information and was reported to experience stability and loading issues. In contrast, the new application-based model incorporated real-time queue monitoring, automated notifications, and clearer scheduling information. This study aimed to compare outpatient waiting time sand patient satisfaction between the old and new online registration models in an oncology outpatient clinic. This cross-sectional observational study with a comparative design included 317 oncology outpatients recruited between October to December 2025, during a period when both registration models were operational. Participants were classified according to the registration model used (old model, n = 187; new model, n = 130). Waiting time was defined at the interval between the Hospital Management Information System (HMIS)-recorded check-in time and the start of the physician consultation. Patient satisfaction was assessed across the five SERVPERF dimensions. Unadjusted between-group comparisons were performed using the Mann-Whitney U test. Semi-structured interviews were conducted solely to provide supplementary illustrative observations and were not included as a formal qualitative component. The Mean waiting time was 83.10 minutes with the new model and 95.83 minutes with the old model group (mean difference, -12.73 minutes; p = 0.037). Mean overall satisfaction scores were 58.67 and 55.33, respectively (mean difference, +3.34; p = 0.003). Scores for tangibles, reliability, responsiveness, and assurance dimensions were significantly higher among users of the new registration model, whereas empathy scores did not differ significantly between groups (p = 0.071). In this unadjusted cross-sectional comparison, use of the new registration model was associated with modestly shorter waiting times and higher patient satisfaction, although overall waiting times remained prolonged. These findings support the integration of real-time digital features into hospital registration systems while highlighting the need for longitudinal studies to confirm their effectiveness and for strategies to ensure equitable access among patients with limited digital literacy. Keywords: Oncology, online registration, outpatient services, patient satisfaction, SERVPERF, waiting time]]>
