What is a duplicate finding – and why does it arise in the preoperative process?
A duplicate finding occurs when a diagnostic test is performed again even though a meaningful result for the same clinical question already exists. In the preoperative pathway – from referral by the office-based practice through the pre-anaesthesia clinic to the ward – responsibility for the patient changes hands several times. Information can be lost at each of these transitions: the previous finding exists only on paper, was not fully transferred to the record or simply cannot be found at the time of the examination. The treating physician then opts for a repeat examination out of a duty of care – not out of carelessness, but because reliable information is missing.
How much do unnecessary repeat examinations cost hospitals and health insurers?
Reliable, isolated cost figures for duplicate diagnostics alone are rare in Germany and Austria. Health insurers do not record them as a separate category, and relevant enquiries to statutory health insurers about exact case numbers usually go unanswered. The scale of the underlying process inefficiency can nevertheless be gauged: a widely cited McKinsey analysis put the annual savings potential of digital health technologies in Germany at around €34 billion in total, equivalent to around 12% of healthcare expenditure at the time. This is not an isolated figure for duplicate diagnostics, but it indicates the order of magnitude at which information loss and duplicated work affect the healthcare system.
The problem can be shown more concretely using X-ray diagnostics: according to BARMER, every resident in Germany statistically receives 1.7 X-ray examinations per year, and computed tomography examinations increased by around 40% between 2014 and 2017. The X-ray record (Röntgenpass) was introduced explicitly so that physicians can recognise whether a comparable image already exists – an admission that the lack of an overview of previous findings is a structural rather than merely anecdotal problem.
What does the current guideline on preoperative diagnostics say about routine tests?
The joint recommendation on preoperative evaluation by the German Society of Anaesthesiology and Intensive Care Medicine (DGAI), the German Society of Surgery (DGCH) and the German Society of Internal Medicine (DGIM), updated in 2024, is clear on this point: routine laboratory screening should not be performed. Further tests – laboratory work, ECG, imaging – are only indicated if the medical history and physical examination provide a specific indication that actually affects perioperative management. The guideline thus explicitly makes a complete, structured medical history the prerequisite for forgoing additional diagnostics – not as an option, but as the clinical basis for the decision.
| Approach | Trigger for diagnostics | Consequence for duplicate diagnostics |
|---|---|---|
| Routine screening without reference to history | Standard protocol, regardless of the individual case | High risk of unnecessary repeat examinations |
| History-based, risk-adapted diagnostics | Specific indication from a complete medical history or physical examination | Diagnostics only when they actually change management |
The practical challenge is that a “complete medical history” only serves as a basis for decisions if it is actually complete, structured and accessible to everyone involved. This is exactly where the smart medical history vs. digital questionnaire comes in: a static history form documents answers, while a smart medical history checks them for completeness and plausibility before they reach everyday clinical practice.
How does a structured digital medical history close the information gap?
medudoc records the medical history adaptively and continuously checks the information for completeness. Using Medical Reasoning, the platform identifies gaps and abnormalities in the recorded data and asks targeted follow-up questions – information that medical staff would collect anyway, but which is available in structured form before the face-to-face patient contact. An important point of context: Medical Reasoning does not make any medical decision. It prepares information for the physician’s assessment; the decision as to whether a previous examination is sufficient or a new one is required always remains with the physician.
Three elements are particularly relevant for avoiding duplicate diagnostics:
- Structured recording of medication and pre-existing conditions instead of free text, making the data traceable and machine-readable.
- Completeness check during the medical history process, which makes gaps visible before the patient arrives at the outpatient clinic.
- HIS integration via FHIR, so that medical history data and existing findings are available where the next decision is made, instead of remaining in a separate paper record.
This integration into the existing hospital IT landscape is not a side issue: without continuous interfaces between referral, medical history, outpatient clinic and ward, even the best medical history remains an isolated data set that can be lost again at the next handover point. The link between fragmented processes and avoidable duplicated work is also described in the article digital medical history as a blind spot in the surgical process.
What effect does this have for hospital management – and for payers?
From an economic perspective, the calculation is easy for hospital management to follow: every avoided repeat examination, which would have offered no additional medical benefit, saves staff time, equipment capacity and – in the case of imaging – additional radiation exposure. For health insurers as payers, the same principle applies at system level: every examination that is billed again without new diagnostic insight ties up funds that are then missing elsewhere in the healthcare system.
Reliable in-house figures on the reduction of duplicate diagnostics through medudoc are not currently available – this would require hospital-specific before-and-after surveys, which medudoc has not yet carried out. What is documented is the time effect of a structured digital intake overall: the University Hospital Würzburg study shows, for video-assisted patient education, an 81% shorter median physician discussion time before cholecystectomy and a 72% shorter one before colon resection; patients’ understanding and satisfaction remained high. A complete medical history checked in advance is the prerequisite for this time actually being spent on the patient and not on searching for missing previous findings.
What does this mean in practice for the pre-anaesthesia clinic?
In the pre-anaesthesia clinic, the two effects meet particularly clearly: in a randomised trial by Salzwedel et al. (2008), the pre-anaesthesia interview took a mean of 17.6 to 23.1 minutes per patient. Part of this time arises because missing or incomplete previous findings first have to be requested or obtained on site. If the medical history is already complete and structured, the physician’s discussion can focus on the actual risk assessment instead of collecting basic information again. The article preoperative intake process describes in detail how this affects the overall distribution of time in the clinic. The link between a complete medical history and time gained for high-risk patients is explored further in the article more time for high-risk patients through a smart medical history.
Conclusion
Duplicate diagnostics are rarely a medical problem – they are an information problem at the transitions of the preoperative process. The current guideline on preoperative evaluation explicitly makes a complete medical history the prerequisite for forgoing additional diagnostics. A structured digital medical history with a completeness check and continuous HIS integration is therefore not merely a convenience feature for patients, but a direct lever against avoidable costs – for the hospital as well as for payers. The digital preoperative workflow of medudoc shows how this approach is embedded in the entire preoperative pathway.
