Correlation between Body Mass Index and Radiation Dose Metrics in Adult Thorax and Abdomen Computed Tomography Examination: A Cross-sectional Study

Introduction: Computed Tomography (CT) procedures contribute significantly to medical radiation exposure and therefore necessitate the implementation of optimisation measures that balance diagnostic image quality with patient safety. Body Mass Index (BMI) influences radiation absorption; however, standard CT protocols do not adequately account for patient-specific body dimensions. Aim: To analyse the relationship between BMI categories and radiation dose metrics—volumetric CT Dose Index (CTDIvol), Dose-Length Product (DLP), Effective Dose (ED) and SizeSpecific Dose Estimates (SSDE)—while examining genderbased and protocol-specific differences in adult thoracic and abdominal CT examinations. Materials and Methods: This Cross-sectional study was conducted at the Department of Radiodiagnosis, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune, India, from April 2025 to July 2025. The study included adult participants (aged 18-70 years) who underwent thoracoabdominal CT examinations 2025 at a tertiary care centre. A total of 200 participants were classified according to the World Health Organisation (WHO) BMI classification as underweight (