Time-paid workers, including those paid by the hour or by the day, are structurally characterized by a wage system directly tied to working hours. As a result, they often experience irregular work schedules and higher income volatility compared to sal...
Time-paid workers, including those paid by the hour or by the day, are structurally characterized by a wage system directly tied to working hours. As a result, they often experience irregular work schedules and higher income volatility compared to salaried or annually contracted workers. Since fluctuations in working hours and wages can affect disposable resources, time available for health behaviors, and levels of stress, it is necessary to examine how such volatility impacts the health of time-paid workers. However, despite the increasing prevalence of nonstandard employment due to labor market flexibilization, research on the health of time-paid workers remains insufficient. Therefore, this study aimed to construct an exploratory preliminary health impact model centered on time- paid workers and to empirically analyze the effects of working hour and wage levels, their instability, and related policy interventions on health behaviors and subjective health.
The objectives of this study are as follows: 1) to construct a preliminary health impact model reflecting the multidimensional characteristics of time-paid workers, based on prior research and empirical data analysis; 2) to assess how the levels and instability of working hours and wages influence health outcomes; 3) to evaluate the effects of labor policy implementation on the health of time-paid workers.
To achieve these objectives, first, an exploratory preliminary health impact model was developed by linking prior theories with an empirical analysis of the Korean Economically Active Population Survey supplementary survey. Second, using data from the Korean Labor and Income Panel Study (2005–2023), correlated random effects models were employed to analyze the impact of working hours and wages on health behaviors and subjective health. Finally, the effects of two policy interventions—the 2018 minimum wage increase and the 2022 implementation of paid holidays for private-sector workers—were estimated using propensity score matching and Difference-in-Differences (DID) models.
In Study 1, a preliminary health impact model was constructed by linking conceptual frameworks on precarious employment and health from prior research with five key health impact pathways reflecting the characteristics of time-paid workers (working hours, wages, working environment, psychosocial factors, and material resources). Furthermore, empirical data analysis confirmed that these health impact pathways align with the reality of time-paid workers. The presented preliminary model served as the analytical framework for the empirical analyses in Study 2 and Study 3.
In Study 2, a dynamic panel model with lagged dependent variables was estimated using the correlated random effects approach to examine the effects of working hours and wages on the subjective health and health behaviors of time-paid workers. Summarizing the analysis of the levels and instability of working hours and wages, a certain level of working hours must be secured to have a positive effect on self-rated health, while a decrease in working hours had a negative effect. Regarding health behaviors, the probability of current exercise increased as the hourly wage level rose, whereas it decreased when an event of monthly wage increase occurred. A rise in hourly wage level reduced the probability of current smoking. For heavy smoking more than 20 cigarettes per day, the smoking amount increased or decreased among smokers accompanying changes in working hours. The probability of drinking three or more times a week increased when working hours or wages increased, and decreased when wages fell.
In Study 3, a Difference-in-Differences (DID) model was used to evaluate the effects of the 2018 minimum wage increase and the paid holiday policy on time-paid workers. Regarding the minimum wage increase, there was no difference in total wage changes between the treatment and control groups due to the reduction in working hours corresponding to the hourly wage hike; consequently, no positive effect was observed in health-related variables. In the case of the paid holiday guarantee policy, the treatment group's working hours decreased more than the control group's due to the policy implementation, but this was accompanied by a negative impact on wages, also resulting in no positive effect on health-related variables.
This study has several limitations. It was limited to using subjective health and self-reported health behaviors as outcome variables, and did not include objective health indicators such as diagnosed conditions or disease prevalence. Additionally, due to data constraints, there may be limitations in the representativeness of the sample. Interpretation of policy effects in the DID analysis also requires caution due to factors such as phased implementation of the policy, discrepancies between legislation and actual enforcement, and heterogeneity within the control group.
Despite these limitations, this study holds significance in that it illuminates the health problems of time-paid workers from the perspective of wage determination mechanisms and employs a multi-layered approach using the construction of an exploratory preliminary model, sophisticated dynamic panel data analysis, and policy evaluation. In particular, it precisely analyzed the health effects by considering not only the absolute levels of working hours and wages but also their instability, lagged effects, and cumulative effects; furthermore, it derived policy implications by empirically examining the effects of the minimum wage increase and the paid holiday policy. Since neither policy showed positive health effects due to the negative impact on total wages despite hourly wage hikes or reduced working hours, the results demonstrated that institutional designs strengthening the stability of both wages and employment are necessary for improved working conditions to lead to actual health promotion. These results provide useful evidence for the design and reform of labor policies that reflect the characteristics of different wage determination structures.