How do occupational stressor-strain effects vary with time? A review and meta-analysis of the relevance of time lags in longitudinal studies

Through a meta-analysis of longitudinal studies from 68 samples, this study examines the role of time in three types of occupational stressor-strain effects. First, this study reviews the extent to which correlations between stressors and strains when both are measured at the same time point (i.e. synchronous effects) change with the passage of time. Second, this review examines the extent to which stressors predict increases in strain (i.e. lagged effects) and whether these effects vary across different time lags. Third, this paper considers the extent to which strains predict increases in stressors (i.e. reverse causation effects), and whether these effects vary across different time lags. Results indicate that synchronous effects tend to increase over time, suggesting that the effects of chronic stressors build up through cumulative exposure. Lagged effects were generally small but their magnitude increased over time for about three years before declining, whereas the average size of reverse causation effects was also small but tended to increase across time. The lagged and reverse causation effects were highly variable, especially among studies with sample sizes under 500, suggesting that large sample sizes are needed to detect them reliably. Implications for longitudinal occupational stress theory and research are discussed.