Objectives <p>Oral cavity squamous cell carcinoma (OCSCC) is one of the most common malignancies affecting the oral region and requires accurate imaging assessment for staging and treatment planning. However, variability in radiologic interpretation may lead to inconsistencies in clinical decision-making. The aim of this study was to develop and evaluate a structured radiologic checklist (NECKCHECK) to improve diagnostic accuracy and interobserver agreement in the imaging assessment of OCSCC.</p> Materials and methods <p>NECKCHECK was developed following a comprehensive narrative review of the literature focusing on relevant staging features of OCSCC using computed tomography (CT) and magnetic resonance imaging (MRI). Key radiologic parameters were organized into a digital checklist designed to guide systematic image interpretation. A concordance study was performed in which otolaryngologists independently evaluated anonymized CT and MRI examinations of patients with OCSCC, both with and without checklist support. Expert radiologist assessment served as the reference standard. Interobserver agreement was assessed using Cohen’s kappa coefficient, and diagnostic accuracy was measured as the proportion of correct responses.</p> Results <p>Use of the checklist significantly improved interobserver agreement, with mean Cohen’s kappa increasing from 0.44 to 0.72. Diagnostic accuracy also improved significantly, with correct responses increasing from 67.1% to 84.7% (<i>p</i> &lt; 0.001). Perfect agreement was achieved for key parameters such as tumor size and depth of invasion.</p> Conclusions <p>Implementation of a structured radiologic checklist improves both diagnostic accuracy and interobserver agreement in the imaging evaluation of OCSCC.</p> Clinical relevance <p>NECKCHECK may support more standardized radiologic assessment of oral cavity squamous cell carcinoma and improve multidisciplinary clinical decision-making in oral cancer management.</p>