Objective To investigate the effect of optimized radiological examination strategy on iatrogenic radiation exposure in severe trauma patients so as to provide scientific basis for standardized application of radiological examination.Methods A controlled, three-stage intervention study from April 2010 to November 2011 was carried out.From April 2010 to July 2010, a pre-intervention study was conducted and enrolled 60 patients [43 males, 17 females;age (50 ± 14)years, age range 23-78 years].From August 2010 to March 2011, optimized strategies of radiological examination were implemented, including improving clinicians' knowledge to the standardization of radiological examination and iatrogenic radiation injury and limiting frequency of CT scans through the electronic medical record.From April 2011 to November 2011, post-intervention study was conducted and enrolled 100 patients (81 males, 19 females;age (47 ± 14) years, age range 18-79 years].During this period, major trauma patients were analyzed with respect to the clinical information, radiation examination frequency, ionizing radiation dose and influencing factors.Radiation examination frequency and radiation dose were compared before and after the intervention.Results Radiological examinations were mainly X-ray and CT before the implication of optimized strategies.Of the 60 patients, median frequency of X-rays and CT scan was 6.0(3.0-11.0) and 10.0(8.0-13.8).Median frequency of CT scan was positively correlated with the injury severity score (ISS) and ICU length of stay (r =0.369 and 0.523, P ＜ 0.05).Of the 100 patients, median frequency of CT scan was significantly reduced after the optimization of radiological examination (8.0 vs.10.0, P ＜ 0.05).Total frequency of radiological examination was significantly reduced as well (13.6 vs.17.8, P ＜0.01).There was no significant difference in the treatment success rate before and after the optimization of radiological examination (85.0％ vs.88.3％, P ＞ 0.05).When the frequency of head and chest CT scan was limited, the frequency of radiological examination, radiation exposure and radiological examination expenses were greatly reduced.Conclusions Too much X-ray,CT or other radiological examinations are noted in major trauma patients during the treatment period.Improved understanding of radiation-induced injury, optimizing radiological examination and controlling the repeated radiological examinations of the same site contribute to reducing iatrogenic radiology exposure without affecting the outcome.