General practitioners’ adoption of a new diagnostic clinic for functional somatic disorders: build it and they will come - but only when invited

Imagine a patient who has spent years feeling unwell, with physical symptoms that doctors cannot explain by any single disease. They move from one specialist to another, undergoing tests that come back normal, yet the pain, fatigue, or dizziness persists. This frustrating cycle is common for people with functional somatic disorders, a condition where the body's systems are not working correctly even though no structural damage is found. In many healthcare systems, a general practitioner acts as the gatekeeper, deciding when a patient is ready to see a specialist. If the gatekeeper does not know about a new, helpful service, or does not understand how to use it, that service remains empty, and the patient continues to suffer. The question for health systems is not just how to build a better clinic, but how to get the doctors who see patients every day to actually send them there.

In the Central Denmark Region, researchers set out to answer this question by opening a new diagnostic clinic specifically for these difficult cases. The clinic was designed to offer a quick, thorough assessment in a single visit, aiming to give patients answers much sooner than the traditional, specialized hospitals could. The team wanted to see if simply opening the doors and sending out information would be enough to get general practitioners to refer their patients. They tracked every general practice in the region over several years, watching who sent patients and who did not, while also talking to the doctors to understand their thinking. What they found was a clear lesson in how medical services actually take root: building a new facility and broadcasting its existence did not, on its own, change behavior. The clinic only began to fill up when researchers personally called the doctors to invite them to use it.

The study began in 2019 when the new clinic opened at a regional hospital. It was a specialized track within a general medical center, designed to see adults who had been struggling with unexplained physical symptoms for between six months and three years. The goal was to catch these patients earlier than the usual specialist departments, which often only accepted cases that had been going on for many years. The clinic offered a unique promise: a single visit where a specialist would look at the whole picture, rule out other diseases, and provide a clear diagnosis and management plan. To make this work, the clinic needed general practitioners to recognize which of their patients were the right fit and to send them over.

The researchers watched how this new service was received by all 340 general practices in the region. They measured adoption by seeing how long it took for a practice to send its first patient. They also looked at whether practices kept sending patients after the initial study period ended. To encourage use, the team tried two different approaches. First, they used "one-to-many" methods, which are like mass mailings. They sent emails, posted updates on a professional website used by doctors, and mailed physical leaflets to every practice. Second, they used "one-to-one" outreach, where researchers made direct, unscheduled phone calls to individual doctors to explain the clinic and ask if they would try it.

The results showed that the mass communications had almost no effect. Despite reaching every single practice with information, the clinics remained quiet for a long time. The doctors who received the emails and leaflets largely did not change their habits. However, the direct phone calls made a visible difference. When a researcher picked up the phone and spoke directly to a doctor, that doctor was much more likely to start referring patients. The study found that 60 percent of the practices eventually sent at least one patient during the trial period, but this only happened after the team actively engaged with them personally.

The researchers also looked at which types of doctors were most likely to adopt the new service. They found that group practices, where several doctors work together, were much more likely to refer patients than solo practitioners working alone. They also noticed that younger doctors were more willing to use the clinic than older ones. This suggests that the structure of a practice and the age of the doctors play a significant role in how quickly new medical tools are accepted.

A major hurdle for the doctors was figuring out exactly who should be sent to the clinic. The criteria were described as a "sweet-spot paradox." Doctors felt that patients needed to be sick enough to need help, but not so complex that they belonged in a different, more severe department. They also worried that the clinic was part of a research trial where patients might be randomly assigned to receive standard care instead of the new assessment. Many doctors felt it was unfair to send a patient on a referral letter only to have them potentially miss out on the new service. This uncertainty made them hesitant to act.

Once the research trial ended and the clinic became a permanent routine service, something interesting happened. The number of referrals roughly doubled. Doctors who had been hesitant during the trial period started sending patients, and those who had already been using the service continued to do so. The monthly rate of referrals jumped from about 11 to 22 per month. This suggests that once the service was established and doctors felt comfortable with it, the behavior became self-sustaining. The doctors who had tried it once found it useful enough to keep using it, and they began to trust the process enough to refer more patients.

The study concludes that simply creating a new medical service and telling people it exists is not enough to ensure it is used. In a system where general practitioners decide who gets specialist care, the service must be actively introduced to them through personal contact. The researchers found that mass information campaigns failed to move the needle, but direct, one-on-one conversations worked. Once that initial connection was made and the service proved its value, the doctors continued to use it without needing constant reminders. The path to a successful new clinic, therefore, is not just about the medical expertise inside the walls, but about the human effort required to build a bridge between the doctors in the community and the specialists in the hospital.