Measuring Chronic Stress in the Emergency Medical Services

This study validates an instrument assessing work-related chronic stress in emergency medical services (EMS) personnel. The instrument was distributed to a systematic probability sample of EMS personnel (N = 1633). Exploratory factor analysis revealed a two-factor, 34 item solution (Kaiser-Meyer-Olkin = .943, chi(2) = 23344.38, df = 561, p <= .001). Confirmatory factor analysis suggested a two-factor, 20 item solution (chi(2) = 632.67, df = 168, p < .001, root mean square error of approximation = .06, comparative fit index = .92, Tucker-Lewis Index = .91, standardized root mean square residual = .04). The factors demonstrated good internal reliability as well as acceptable convergent, discriminant, and predictive validities. Chronic workplace stress may lead to psychological distress; this validation contributes to the tools available to assess the health and well-being of EMS providers.