Objective: Standard assessment of pediatric obsessive-compulsive disorder (OCD) patients includes ratings of insight, avoidance, indecisiveness, sense of responsibility, pervasive slowness, pathological doubting, and obsession-free intervals. The present study aims to identify pre-treatment associations of these clinical features to symptom severity and symptom dimensions as well as to describe and analyze the long-term levels and distribution in different treatment responder groups. Method: Severity ratings as well as clinical feature ratings were evaluated in 268 pediatric OCD patients using the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) at seven time points before, during, and up to three years after first-line cognitive-behavioral therapy. The CY-BOCS auxiliary items were evaluated on the basis of three symptom severity trajectory classes: acute, slow, and limited responders. Results: Insight, avoidance, pervasive slowness, and obsession-free intervals were positively associated with pre-treatment symptom severity. Symptom dimensions were associated with different auxiliary items. At three-year follow-up, the limited responder class had higher scores than the acute and slow responder classes on all items except for responsibility. Conclusion: The CY-BOCS auxiliary items are closely related to symptom dimensions and partly to symptom severity. The features appear to be dynamic concepts prone to change, yet, less so in patients showing limited long-term treatment response.