Sickness absence is an increasingly important operational and policy concern in the Netherlands, particularly in the context of labour shortages, demographic ageing, and pressure on workforce availability. However, registered sickness absence does not reflect illness alone. From an absence-threshold perspective health complaints, fatigue and private circumstances lead to reported absence only when they cross a threshold shaped by institutional incentives, employment conditions and individual circumstances. This thesis asks: To what extent are national social security frameworks, individual factors, including worker profile and job context, and exogenous factors associated with sickness absence behaviour of logistics workers in the Netherlands, Germany, and France?

The study applies a within-firm, cross-country comparative design using Picnic’s frontline operations, allowing different national sick-leave regimes to be examined while keeping the employer and broad work context relatively comparable. Data covers warehousworkers and delivery drivers in employee-week observations from 2024–2025. A structured institutional policy analysis is combined with analysis of a novel individual-level set of employee-, operational- and contextual variables to explain sickness absence patterns. Exploratory analyzes compare spell-duration distributions with national arrangements concerning waiting days, medical certification, wage replacement, and employer obligations. Ordinary least squares models analyze weekly sickness absence rates, supported by robustness models, while Cox proportional hazards models examine sickness-spell duration.

The findings show that sickness absence is multidimensional, with different determinants shaping different absence margins. In the Netherlands, frequent one-day absence is consistent with a relatively low reporting threshold resulting from the absence of mandatory medical certification and the conditional use of waiting days. Shopper timing patterns and cold-zone exposure further suggest that some short-term absence may be discretionary or operationally avoidable. By contrast, the Dutch long-term burden may reflect the interaction of prolonged employer wage continuation with an older, longer-tenured workforce and the positive association between permanent contracts and absence. In Germany, day-one certification appears to limit the shortest spells, while the absence of waiting days and full wage replacement during the first six weeks are consistent with higher short- and medium-term absence. German absence is also strongly associated with local operational conditions, including staffing, Captain absence, lateness, performance, and disruptions. France combines waiting days and day-one certification with the lowest absence frequency, while its negative tenure patterns suggest that absence may be more closely related to workforce retention than to long-duration benefit incentives.

Across countries, the most relevant non-policy determinants concern employee profile, scheduling, team context, and external shocks. Age is most clearly associated with long-term absence, while gender is the most consistent correlate of higher absence rates, although this likely reflects legitimate recovery rather than operationally avoidable absence. Tenure and contract type are more context-dependent and appear to capture workforce selection, retention, and employment attachment. Recurring operational findings include recent scheduling intensity among Shoppers, Chilled and Frozen shift exposure, and local Captain context and disruption sensitivity among Runners. Overall, national policy alone does not explain sickness absence; rather, policy interacts with workforce and operational conditions, creating actionable opportunities to improve reliable attendance and productivity.


These findings imply that sickness absence should not be addressed as one uniform problem. The cross-country patterns suggest that Dutch high short-term absence and persistent cases, through operational interactions, are related significantly to certification requirements, waiting days and financial incentives. This provides a strong argument for the Ministry of Social Affairs and Employment to their ability of mitigating these margins through the respective levers, after assessment of the true recovery need of this population. Operationally, logistics' should monitor absence short- and long-term absence separately through an aggregate dashboard across roles and countries, as results show distinctly different relationships per margin. Operational priorities include preventing timing- and cold-zone-related short absence and strengthening long-term reintegration in the Netherlands, improving local performance-, and disruption management in Germany, and supporting job fit, and talent retention among French Shoppers.

The results are associative rather than causal and are based on registered sickness absence within one company. The data do not directly measure health, private circumstances or presenteeism, while employee selection into contracts, shifts, teams, and locations may influence the estimated associations. The cross-country findings should therefore not be interpreted as pure national policy effects or automatically generalised beyond comparable frontline logistics settings. Future research should combine administrative data with employee or occupational-health information and evaluate policy changes or operational interventions through quasi-experimental designs or phased field trials.
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