The topics were matched regarding to age , sex, and race. A complete of 20 variables with 44 conditions were used to regulate for individual characteristics that might confound or change the association between polluting of the environment and loss of life. These variables, that have been considered to be of potential importance on the basis of previous studies, included individual risk factors that data had been collected in the CPS II questionnaire. Seven ecologic covariates attained from the 1980 U.S. Census had been also included. These variables had been included at two amounts: as the common for the metropolitan statistical region and as the difference between your average for the ZIP Code of home and the average for the metropolitan statistical region. Additional sensitivity analyses had been undertaken for ecologic variables that were available for just a subgroup of the 96 metropolitan statistical areas .Bertolini. Aetna's focus is on supporting those affected get the help they have to move forward out of this unthinkable event. The Aetna Behavioral Health College student and Employee Assistance Program professionals who will answer the telephone have experience helping people through traumatic occasions, and are available now. Anybody, of insurance regardless, is welcome to get hold of Aetna's counselors for help, referrals or support for further assistance. The number to call is 1-888-AETNA-EAP . Individuals and families may want to reference the next materials also.