“…Covariates were selected based on what was supported in the literature as being factors of safety climate and union membership, as well as taking into consideration whether the variable was collected in the QWL. The available literature identifies sex, race, age, education, private vs. public sector, work status, and state of residence being strong indicators of union membership with males, non-whites, those middle-aged, individuals who were high school graduates or had some college education, those who worked in the public sector and government, full-time employees, and individuals from certain states (e.g., Hawaii, New Jersey, New York, Washington), respectively, having greater likelihood of being in a union ( Bureau of Labor Statistics, 2018a , Benson and Griffin, 1988 , Hirsch and Berger, 1984 , Hirsch et al, 2001 , Hundley, 1988 , Kokkelenberg and Sockell, 1985 , Mishel, 2012 , Schur and Kruse, 1992 , Silverblatt and Amann, 1991 ;). Following the literature, individual demographics included in the analysis were: age (18–29, 30–39, 40–49, 50–64, 65 and above), sex (male or female), educational level (less than a high school diploma, high school graduate, some college/associate’s degree, bachelor’s degree, or beyond bachelor’s degree), work status (part- or full-time), race/ethnicity (non-Hispanic white, non-Hispanic black, and other/unclassified), region of residence (northeast, Midwest, south, west), and respondent annual income ($1-$9,999, $10,000-$14,999, $15,000-$19,999, $20,000-$24,999, or $25,000 and greater).…”