“She called in sick with back complaints. Two weeks later, a colleague saw her on Instagram, sweating through an intense HYROX training session.”
Sick leave in healthcare has been a persistent issue for years, and the figures show the problem isn't resolving on its own. According to figures from the Dutch national statistics office (CBS) (via AZW StatLine), sick leave in healthcare and welfare averaged 7.5% in 2025, with a clear outlier in nursing, care and home care (VVT) of 9.5%. In the second quarter of 2026, sick leave in the health and welfare sector rose further still, to 7.6% compared with 7.1% a year earlier. For healthcare employers, this means not only staffing pressure, but also mounting financial pressure.
Most of it is legitimate — but not all of it
The vast majority of sick leave in healthcare is, understandably, entirely legitimate: the physical and mental demands of the work are high, and that's rightly reflected in the figures. In a small share of cases, however, a well-founded, substantiated suspicion arises that the reported incapacity for work doesn't, or doesn't fully, match reality. That's precisely why we never work on the basis of a loose suspicion: every investigation starts with a careful assessment of whether further investigation is proportionate and subsidiary, meaning whether the goal can't be achieved by a less invasive means.
Signs that can warrant further investigation
In practice, we see that a request for investigation usually arises from a combination of signals, not a single fact:
- A concrete tip, for example from a colleague or manager
- Repeatedly failing to meet reintegration agreements
- Poor or obstructive cooperation with the recovery or reintegration process
- Observed behaviour that doesn't match the reported complaints
Two examples from practice
Two situations come up relatively often. In the first, an employee on the healthcare provider's payroll is on sick leave, but turns out to be carrying out work for another party during that same period, for example as a freelancer. In the second, an employee reports physical complaints severe enough to prevent working, while that same person trains intensively, for example in heavy strength training or a competitive format such as HYROX. Neither example is proof on its own, but they're exactly the kind of discrepancy that can justify a legitimate investigative question.
What we investigate, and what we don't
We deploy two methods for this: surveillance and digital research using public sources. During surveillance, our investigators objectively record what they observe in public places, such as departure times, destinations or physical activity. Digital research is limited to what can be found through public sources (such as a publicly visible social media profile), always within GDPR limits. We never hack, wiretap or crack anything, and we never place hidden devices without a legal basis. Read more about what is and isn't allowed on our page Is hiring a private investigator legal?
Our approach in three steps
- We open a case and gather as much relevant information as possible about the matter and the person involved, during a free intake call with you as the employer.
- We draw up a concrete plan of approach, with explicit regard for proportionality and subsidiarity: what means is necessary, and is it not disproportionate to the goal?
- We objectively record our observations in a factual report that stays as close to the facts as possible, without interpretation or assumptions, which you can use with, for example, an occupational physician, a UWV procedure, or, where relevant, legal proceedings.
For healthcare employers
Recognise any of these signals within your organisation? Feel free to get in touch, no obligation. During a free intake call, we discuss your situation and advise you, even if that advice is that an investigation wouldn't be proportionate in your case. Read more about our approach and rates for sick leave cases on our page Sick Leave Fraud Investigation.
