Clinical trial NCT05380570: Epidemiological Study of Korean Radiation Workers
Official title: Health Effects Associated With Occupational Radiation Exposure Among Korean Radiation Workers (Korean Radiation Workers Study)
Study type: OBSERVATIONAL
Overall status: ACTIVE_NOT_RECRUITING
Conditions: Occupational Exposure to Radiation
Neoplasms, Radiation-Induced
Leukemia, Radiation-Induced
Radiation Effects
Keywords: Ionizing radiation
Cohort study
Radiation workers
Radiation-Induced diseases
Lead sponsor: Korea Institute of Radiological & Medical Sciences
Sponsor class: OTHER_GOV
First posted: 2022-05-19
Enrollment: 196379
Sex: ALL
Minimum age (years): 15
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Korean radiation workers in the national dose registry

Brief summary: Health risks of radiation exposure in the moderate-to-high dose range have been well established. However, the risk remains unclear at low-dose ranges with protracted low-dose rate exposure, which is typical of occupational exposure. The purpose of this study is to construct a cohort of Korean radiation workers and to assess health effects associated with occupational radiation exposure. The study population is expected to be about 190,000 Korean radiation workers who have been registered with the Nuclear Safety and Security Commission since 1984. The national dose registry, the national cancer registry, the national vital statistics registry, and the national health insurance data are collected based on the Nuclear Safety Act. Through the linkage of those collected data, we will evaluate radiation-induced health risks including cancer and non-cancer diseases.

Detailed description: The study population of this study is approximately 190000 Korean radiation workers registered with the Nuclear Safety and Security Commission since 1984. Diagnostic medical radiation workers were not included in the study population. The national dose registry, the national cancer registry, the national vital statistics registry, and the national health insurance data for radiation workers are collected retrospectively or prospectively based on the Nuclear Safety Act. Through the linkage of those collected data, we will evaluate radiation-induced health risks including cancer and non-cancer diseases. This data collection will be continued at 5-year intervals to update information on existing study participants and recruit newly hired workers if possible.

Age- and sex-specific standardized incidence and mortality ratios will be calculated for overall comparisons of cancer and non-cancer disease risks with general population. For dose-response assessment, excess relative risk (per Gy) and excess absolute risk (per Gy) will be estimated with adjustments for age and potential confounders, such as lifestyle factors and socioeconomic status.

Eligibility criteria: Inclusion Criteria:

* Korean radiation workers in the national dose registry (except for diagnostic medical radiation workers)

Exclusion Criteria:

* Unidentified personal identification numbers
* Foreigner

Primary outcomes:
measure: Radiation-induced cancer risk
timeFrame: year 4
measure: Radiation-induced cancer risk
timeFrame: year 9
Secondary outcomes:
measure: Radiation-induced non-cancer risk
timeFrame: year 4
measure: Radiation-induced non-cancer risk
timeFrame: year 9
Other outcomes:
Locations:
city: Seoul
country: Korea, Republic of
facility: Korea Institute of Radiological & Medical Sciences
state: Nowon-gu
Study officials:
References:
citation: Seo S, Lim WY, Lee DN, Kim JU, Cha ES, Bang YJ, Lee WJ, Park S, Jin YW. Assessing the health effects associated with occupational radiation exposure in Korean radiation workers: protocol for a prospective cohort study. BMJ Open. 2018 Mar 30;8(3):e017359. doi: 10.1136/bmjopen-2017-017359.
citation: Lee D, Cha ES, Park S, Sung H, Noh E, Jeong H, Jang WI, Seo S. Cohort Profile: The Korean Radiation Workers Study (KRWS). Int J Epidemiol. 2024 Apr 11;53(3):dyae060. doi: 10.1093/ije/dyae060. No abstract available.