Abstract
BACKGROUND: Research on precarious employment (PE) has increased in recent decades, highlighting its association with health-related problems. However, standardized multidimensional measures of PE remain limited. This study aimed to develop and validate a multidimensional index of PE tailored to the Danish labour market, incorporating aspects of daily working conditions. METHODS: A cross-sectional study was conducted using a random sample of Danish workers aged 18-45 years, (N = 3,501). The PE Index includes six dimensions, comprising a total of 15 items: instability (2 items), salary (1 item), power and rights (4 items), work task planning (4 items), work time planning (2 items), and workers' collective (2 items), with a score ranging from 0 (no PE) to 100 (most PE). Exploratory factor analysis was conducted to explore factor structure of the PE Index. To assess reliability and inter-item correlation of the individual dimensions, Cronbach's Alpha and Kendall's Tau were applied. To examine predictive validity of the individual dimensions and the PE Index, we conducted adjusted linear regression models between the PE Index (and its individual dimensions) and 1) job insecurity, 2) worker vulnerability - measuring worker-employer relations and 3) WHO-5 Wellbeing Index (mental well-being), respectively. Model fit was assessed using R(2) values. RESULTS: Reliability was strong (α ≥ 0.85) for power and rights and work task planning, while inter-item correlations were moderate for instability (0.29) and workers' collective (0.23), and weak for work time planning (0.11). The PE Index score was statistically significantly associated with job insecurity (β = 0.03, R(2) = 16%), worker vulnerability (β = 0.04, R(2) = 24%) and mental well-being (β = -0.56, R(2) = 12%), with power and rights, work task planning and workers' collective showing the strongest explanatory power. The highest PE Index scores were observed among women, younger workers (< 25 years), and those employed in trade & transport and healthcare. CONCLUSIONS: This study developed and validated a PE Index for Danish workers, capturing daily working conditions. Findings indicate that the PE Index is associated with job insecurity, worker vulnerability, and mental well-being. The 15-item index may serve as a practical tool for future labour market research.