Impact of Work Environment Absent of Natural Light on Vitamin D Levels
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Three types of workers exposed to different levels of natural sunlight will be tested for Vitamin D blood level, PTH, Ca, P, albumin and alkaline phosphatase.
In addition, each tested worker will be asked to fill a questionnaire for demographic, medical and personal habit information.
Vitamin D Deficiency
|Study Design:||Observational Model: Case-Crossover
Time Perspective: Cross-Sectional
|Official Title:||Impact of Work Environment Absent of Natural Light on Vitamin D Levels|
|Study Start Date:||November 2011|
No natural sunlight
one group works in a basement with no natural sunlight
Low level of Natural Sunlight
the second group work in offices with unopenable windows.
High level of Natural Sunlight
The third group works outdoors.