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1* . (Corresponding author) Department of Biostatistics, School of public Health, Hamadan University of Medical Science, Hamadan, Iran. Email: firstname.lastname@example.org. 2. Department of Occupational Health, School of public Health, Hamadan University of Medical Science, Hamadan, Iran. 3. Department of Occupational Health, School of public Health, Hamadan University of Medical Science, Hamadan, Iran.