Variables related to Sun exposure

idVariableDescriptionCollectedFile
LATREGIONLatitude (degrees N) of CC at CT randomization/OS enrollment
*Region of residence at the time of randomization or enrollment, based on the latitude of the responsible clinical center.
Baseline, MainDemographics and Study Membership
WATTSCATWatts ((J/s) per m2) of CC at CT randomization/OS enrollment
*The WATT is a unit of solar irradiance and measures the daily UVB flux reaching the earth, within the wavelength range necessary for vitamin D synthesis. The information is in: Lubin D, Jensen EH, Gies HP. Global surface ultraviolet radiation climatology from TOMS and ERBE data. Journal of Geophysical Research 1998;103 (D20):26061-26091. Categories are based on the WATTs of the clinical center at the time of randomization or enrollment.
Baseline, MainDemographics and Study Membership
LANGLEYSCATLangleys (g-cal per cm2) of CC at CT randomization/OS enrollment
*The Langley is a unit of solar irradiance and relates to the amount that reaches a given area of the earth’s surface. The information is from national weather data on total solar irradiance in the United States and is adapted from Garland and Garland (Do sunlight and vitamin D reduce the likelihood of colon cancer? Int J Epidemiol 1980;9:227-31.) Categories are based on the Langleys of the clinical center at the time of randomization or enrollment.
Baseline, MainDemographics and Study Membership
LATREGIONCADLatitude (degrees N) of CC at CaD randomization
*Region of residence at the time of CaD trial randomization, based on the latitude of the responsible clinical center.
Baseline, MainDemographics and Study Membership
WATTSCATCADWatts ((J/s) per m2) of CC at CaD randomization
*The WATT is a unit of solar irradiance and measures the daily UVB flux reaching the earth, within the wavelength range necessary for vitamin D synthesis. The information is in: Lubin D, Jensen EH, Gies HP. Global surface ultraviolet radiation climatology from TOMS and ERBE data. Journal of Geophysical Research 1998;103 (D20):26061-26091. Categories are based on the WATTs of the clinical center at the time of CaD trial randomization.
Baseline, MainDemographics and Study Membership