Correlation Between Entrance Surface Doses and Body Mass Index (BMI) for Students Undergoing Chest X-Ray Examination, at Olabisi Onabanjo University Clinic

The campus environment is a congregation of students from all over the nation, and the possibility of transmission of contagious diseases such as tuberculosis cannot be ruled out; hence, it is compulsory for all newly admitted students to undergo chest X-ray examination. In this study, the correlation between the entrance surface dose (ESD) and body mass index (BMI) has been investigated. The anthropometric /biodata parameters, such as age, weight, height, and radiographic parameters such as tube voltage (kV), tube current (mAS), and film focus distance (FSD) were collected for 500 students at the clinic. A model equation was used to estimate the entrance surface dose (ESD). Statistical Package for Social Sciences was used to establish the relationship between the radiographic parameters and the body mass index for the newly admitted students. The result of the study shows that the estimated entrance surface dose ranged from 0.02 – 0.63) mGy, with a mean of 0.09 mGy. The tube voltage and the mAs ranged from (68 – 74) kV with the mean of 71kV and (10–30) mAs with the mean of 20 mAs, respectively. The mean of the estimated entrance surface dose for the present study is lower than the diagnostic reference level (DRL) recommended by the International Atomic Energy Agency (IAEA) and the National Radiation Protection Board (NRPB) with values of 0.40 mGy and 0.30 mGy, respectively. A fair correlation with a value of 0.544 exists between the BMI and the entrance surface dose estimated for the study. In conclusion, the chest X-ray examination carried out in the University clinic is within the safe limit; the management may offer their services to the public so as to increase their internally generated revenue (IGR) of the University.