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Investigation on the frequency of medical exposure of X-ray diagnostic equipment in Tianjin

Objective 
To assess the frequency of medical exposure from X-ray diagnostic equipment in Tianjin, and provide recommendations for regulating medical radiation management and rational allocation and use of medical and health resources. 
 
 
Methods 
Using the census method, questionnaries were issued in the form of an administrative document to investigate the basic information on X-ray diagnostic equipment and medical procedure frequency in 687 hospitals (excluding military and armed police hospitals) in 2018. Mean values of frequencies were derived by dividing the number of procedures for each type of X-ray equipment by the total number of permanent residents. 
 
 
Results 
There were 1 562 pieces of X-ray diagnostic equipment (including interventional radiology), with an average of 1.00 unit per 10 000 population. There were 4 782 radiation workers engaged with X-ray diagnostic work (including interventional radiology), averaged on 3.06 workers per unit, with the highest of 5.25 workers per unit in tertiary hospitals and the lowest of 1.18 in ungraded hospitals. The city′s X-ray diagnostic medical exposure came from 8 905 970 medical procedures, including 54.81% for tertiary hospitals, 18.00% for secondary hospitals, 16.21% for primary hospital, and 10.98% for ungraded hospitals. X-ray photography contributed 71.30% with annual frequency of 407.84 examinations per 1 000 population, CT scans 21.81% with annual frequency of 124.74 examinations per 1 000 population, interventional radiology 1.04%, with annual frequency of 5.98 examinations per 1 000 population, and other types of X-ray examinations 5.85% with annual frequency of 33.47 examinations per 1 000 population. 
 
 
Conclusions 
The configuration of X-ray diagnostic equipment in Tianjin is basically reasonable. The frequency of X-ray diagnostic medical exposure is increasing year by year. The rationality of the distribution of X-ray diagnostic examinations needs to be further improved. To reduce dose to population, for the public health and safety is important issues in the future of radiation protection. 
 
 
Key words: 
X-ray diagnosis; Medical exposure; Frequency