Repeating Task-Irrelevant Contexts Does Not Bias Task Choice and Performance in Voluntary Task Switching.

For decades, occupational health frameworks focused on time-related risks such as excessive work hours and nonstandard schedules (; ; ; ), aligning with the logic of fundamental cause theory and emphasizing social conditions such as socioeconomic status and social support, rather than proximal factors, as the fundamental causes of diseases (; ; ). Yet the labor market has changed substantially, and the emerging landscape of precarious work-time arrangements—including long, short, very short, and highly variable hours—presents new risks that traditional frameworks often overlook (; ). U.S. employers increasingly use “just-in-time” scheduling strategies, which prioritize flexibility for firms over stability for workers (; ; ; , ). It undermines workers’ control over their time (; ), erodes work–life balance (), and contributes to health harms, including psychological distress, sleep disturbances, functional limitations, and even mortality in later life (; ; ; ; ). It also generates income inequality, material hardship, and poverty risk (, ; ; ), suggesting that work-hour instability is not just inconvenient but structurally consequential. Given these transformations of work, occupational health frameworks must evolve to fully address the temporal dimension of precarity (). Several key research gaps remain. First, most evidence emphasizes concrete scheduling practices, leaving open whether more general instability in work hours predicts subsequent health change under population-level inference. Second, the gender patterning of health consequences remains underexplored. Because gender stratifies both exposure to precarious work and responses to health strain—women are more likely to interrupt, reduce, or suspend work after health problems, whereas men more often remain employed as health deteriorates (; ; ; )—work-hour instability may surface through different health trajectories by gender. Third, we know little about how these pathways intersect with the healthy worker survivor effect, which may confound the relationship, despite cohort evidence on gendered survivor selection (; ; ).