The Three-Number Test.

Every hospital Geschäftsführer I have worked with can recite, without checking, three numbers about their patients: bed occupancy, case volume, and case mix index. These numbers are live — tracked daily, referenced in weekly meetings, internalised as the pulse of the operation. When I then ask three equivalent numbers about the staff — last twelve months of nursing turnover, last month of departmental overtime, and current-year sick leave days per FTE — the confident recall drops sharply. Perhaps one in five leadership teams can produce all three from memory. The rest promise to check and send them through. Some do. Most forget.

This is not a failure of memory. It is a failure of attention, and the failure of attention is the diagnostic. A hospital leadership team whose internal dashboard tracks occupancy to the bed but cannot approximate nursing turnover within five percentage points has made, through the structure of its attention, a specific decision about what matters operationally. The decision is almost never made explicitly. It is revealed by the test.

The ANCHOR layer of CuraOS exists to surface this pattern and to re-anchor leadership attention on the people who actually run the hospital. Post 1 of this series [previous post] introduced the argument that staff are a hospital’s second customer — the party whose continued presence is as operationally essential as patient flow. This post drills into the specific operational diagnostic that turns the argument into a Monday morning action. The three-number test is not an HR metric exercise. It is the simplest available check on whether the leadership team’s attention is calibrated to the condition of the workforce.

Why these three specifically.

Many numbers could be proposed as the signature metrics of workforce condition. I have settled on these three over a dozen operational engagements because they triangulate in a way that no single number does. Each captures something the others miss. Together they describe a system.

Turnover rate — the trailing indicator. Turnover, measured as the proportion of staff who leave in a rolling twelve-month window, is the most visible and the most delayed of the three. By the time it moves, the condition it reflects has been deteriorating for months. German hospital nursing turnover averaged approximately 1 in 6 staff annually in the most recent large-scale analysis [1] — a figure that varies meaningfully by region, by department, and by hospital culture. The broader international evidence points in the same direction: according to PubMed-indexed research, Aiken and colleagues’ cross-sectional study of 21,050 clinicians across 60 Magnet hospitals reported 47% high burnout among nurses and 32% among physicians, with nurse burnout directly associated with turnover of both nursing and physician staff [2]. Notably, clinicians in that study ranked staffing adequacy, workload control, and work-environment quality as far more important to their retention than wellness programmes or resilience training — a finding that realigns where leadership attention needs to sit. The hospital that does not know its own number cannot know whether it is running at, above, or below benchmark.

Overtime hours — the present-tense indicator. Overtime is the real-time reading. When a department is running structurally short-staffed, overtime rises; when the workforce is stretched but not yet visibly leaving, overtime is where the strain appears first. A leadership team that tracks overtime monthly, by department, in absolute hours rather than as a percentage of base rostered hours, sees workforce strain six to twelve months before turnover catches up. Hospitals that monitor overtime only at aggregate level miss this signal entirely.

Sick leave days per FTE — the cultural indicator. Sick leave, tracked per full-time equivalent across the calendar year, is the indicator most influenced by departmental culture. Individual illness rates vary; departmental averages, aggregated across sufficient staff, reveal something about the working environment that neither turnover nor overtime quite captures. A department whose sick leave runs significantly above hospital average, with no demographic or clinical explanation, is a department under stress — even if the overtime and turnover numbers have not yet moved.

What the three numbers together reveal.

The diagnostic power of the test is not in any single number but in the pattern across the three. Different combinations tell different stories, and the stories are specific.

The operational power of the test lies in how specific the response becomes when the pattern is named. A hospital in open crisis (Pattern 1) needs different interventions from one in early warning (Pattern 2). A captive-workforce department (Pattern 4) has a short runway before external labour-market conditions allow departure; the intervention has to happen before the release valve opens. A hidden-stress department (Pattern 3) often surprises leadership teams, because the workforce has not yet voted with its feet — but cultural attrition is already compounding.

Why leadership avoids the test.

Three structural reasons keep leadership teams from running this test routinely.

The data lives in HR, not operations. In most German hospitals, these three numbers are maintained by the Personalabteilung and appear at Geschäftsführung level only in quarterly reports. They are not part of the weekly operational rhythm. Reframing them as operational metrics — things the Geschäftsführer and the medical directorate should know from memory, not look up in a slide — requires the Personalabteilung and the operational leadership to agree on a shared rhythm. That agreement is unusual.

The numbers, when actually examined, produce uncomfortable conversations. If nursing turnover is 18% in a hospital where the executive team has been assuring the board that workforce stability is solid, the conversation that surfaces the real number is politically difficult. Leadership teams that have been avoiding this conversation will not commission the test that forces it. Until someone names the pattern, the pattern persists.

Overtime in particular is routinely undercounted. Much overtime in German hospitals, particularly in physician grades, is not formally logged or is logged against time-in-lieu arrangements that obscure the true scale. Asking for “last month’s overtime hours, by department, in absolute units” often produces numbers substantially higher than the leadership team has been working with. This finding alone changes how capital allocation, staffing, and retention investment are framed.

What the Schlüchtern ANCHOR work showed.

At Main-Kinzig-Kliniken Schlüchtern, the geriatric department instituted the three-number discipline in early 2020 as part of the broader operational restructuring under the research programme with Prof. Dr. Rainer Sibbel at Frankfurt School [2,3]. The three numbers appear on a single page, reviewed monthly at the department operations meeting. The discipline surfaced an early-warning pattern in one subunit in 2021 that allowed intervention before turnover caught up. By the time the operational programme had been running for three years, the three numbers had become part of the ambient language of the department; junior leaders learned to reference them in the same way they referenced length-of-stay or bed occupancy.

The pattern generalises across specialties. A surgical department that runs the test finds different proportions than a medicine department; an ICU finds different proportions again. What does not change is the usefulness of the triangulation — no single number carries the information that all three together carry.

What to do on Monday.

If you lead a hospital and you suspect your leadership team is running without a live reading of the workforce, the test is simple to commission.

At the next medical-directorate meeting, ask each head of department to state, without notes, the most recent twelve-month nursing turnover rate for their area, the most recent monthly departmental overtime total in hours, and the current-year sick leave days per FTE. The answers will typically fall into three categories. One or two department heads will produce all three from memory with confidence. A larger group will produce one of the three confidently and promise to check the others. The remainder will promise to check all three and come back.

The distribution is the diagnostic. You now know which of your department heads operate with a live reading of their workforce and which operate from quarterly summaries.

Commission a single-page workforce reading for each department, updated monthly, containing these three numbers plus a twelve-month trend line for each. The page goes to department heads, to the medical directorate, and to the Geschäftsführung on a fixed monthly cadence. At the following month’s meeting, ask the question again, from memory. Most department heads will now answer correctly; those who still cannot have revealed a deeper management gap that requires a different conversation.

Do not reward the ritual of having the data available; reward the internalisation of the data into management attention. The test works because the numbers are simple enough that a competent operational leader should carry them in their head the way they carry occupancy and case volume. When they do, the conversation about workforce condition moves from quarterly HR reporting to weekly operational judgment — which is where it needs to be.

The three-number test is not a measurement innovation. The numbers already exist in every hospital’s records. The innovation is the commitment of leadership attention to reading them. That commitment is the ANCHOR layer in its most concentrated form: deciding that the condition of the people running the hospital is a thing leadership is continuously aware of, not a thing that is reported on quarterly.

Three numbers. From memory. No deck. The test takes thirty seconds. The answer you get back describes how much of your own hospital the leadership team is actually paying attention to.