It’s the season for graduation ceremonies. Proud parents and partners, relieved graduates, and a lump in everyone’s throat as that enormous rite of passage is eased by impressive ceremony, thoughtful words, cheap university wine in plastic glasses, and finally by long, late, cheerful family lunches.

My generation began their medical careers in a different world, where competence was implicit. After several decades of serial NHS disappointments, disasters, and scandals, new doctors—fresh and eager, but apprehensive—enter a brave new world.

We now have highly structured foundation and specialist training, revalidation, and, in general practice, one of the world’s largest pay for performance programmes in the form of the Quality and Outcomes Framework (QOF). As I write those letters, QOF, I hear the collective intake of breath from UK GP readers. There’s a moment in Star Wars Episode IV: A New Hope, when Obi-Wan Kenobi shudders as he detects the cries of millions of people as Princess Leia’s home planet Alderaan is destroyed by the evil empire’s Death Star. Believe me, I feel the force. I know that the QOF is controversial. Bear with me.

Introduced in 2004 as part of a new GP contract, the QOF meant that, almost overnight, 25% of GP’s practice income became dependent on meeting a range of clinical, organisational, and patient experience indicators. Electronic records—already well advanced in primary care—were the only way to go, and administrative and nursing staff were redeployed or recruited to deliver protocol driven care for chronic diseases.

A number of studies have examined whether quality of care improved as a result of the QOF; disappointingly, the effects seem to be limited and short term. Perhaps a minority of practices were at last motivated to improve the organisation of care for some common and important chronic diseases. But the effect was short lived, and the downside is sensitive consultations interrupted by electronic tick boxes, along with accusations that the QOF distorts clinical focus, with an emphasis on things that can be measured, rather than what is important.

It was all very predictable. There’s a general principle called “the inverted U” that was first described by Yerkes and Dodson in 1908. As an example, take the care of people after a myocardial infarction. We all know that several medicines have a good evidence base for secondary prevention of ischaemic heart disease—notably antiplatelets, beta blockers, angiotensin converting enzyme inhibitors, and statins. If the organisation of care is poor then these medicines may not be provided or taken, and the quality of care suffers. Make the care happen with incentives, data, and external standards, and the uptake of the evidence based interventions improves; coercion can be a good thing.

But if evidence based care becomes rules based care, then people who shouldn’t be taking—or who don’t want to be taking—one or more of the medicines may end up on them. Quality initially improves with better organisation, and then suffers with continuing coercion: the inverted U. It’s a bit like the Goldilocks story—not too much coercion, not too little.

Malcolm Gladwell writes about the inverted U in his latest book, David and Goliath. One of his examples is the linking of lengthier custodial sentences with reductions in serious crime. It seems pretty straightforward: lock up young men who repeatedly offend, that will get them off the streets so they can’t commit more crimes, and the policy will deter others. Simples. Except that Gladwell describes the good evidence that young men when committing a crime are “in the moment,” so what seems to be a deterrent isn’t—they just aren’t thinking of the consequences. And the good evidence that when more than 2% of the male population are in jail long term, even though they might not be the greatest role models, the ramifications on family life fuel future crimes by the next generation. And the good evidence that there are better results in localities where the law enforcement approach is one of engagement and support into a life outside crime, alongside targeted policing.

Helping people beats coercion. Believe it or not, being kind to people and offering them help has an evidence base. Sure, if sentencing is very lenient then you can find studies showing a more coercive policy reduces crime. But beyond that initial improvement from a low baseline, it’s tough to find good evidence for the “three crimes and its life” policies, which were popular 10 years ago in the United States. It may all seem counterintuitive, but in the US many have revised their rules based approach.

Goldilocks features in economics and astronomy, as well as in the fairy tale and in custodial sentencing. A “Goldilocks economy” is where there is neither too much nor too little growth, neither too much nor too little inflation. A “Goldilocks planet” is one that is in the temperate zone likely to support life—a planet neither too close to, nor too far, from its sun. Could the same principle apply to coercive implementation strategies? Should they be reserved for situations only where short term remedial effects are required to address generally poor performance? Does the pop-up box on the computer system reminding the GP to take the patient’s blood pressure help or hinder great care when the patient has come because their wife of 40 years died last week?

For the QOF, it seems clear that the effects of pay for performance are less than payers would wish, and the policy has had unintended consequences. So when we are struggling with improving the quality of healthcare and considering coercion (making it happen) or support (helping it happen), maybe Goldilocks ought to pop into our heads then too? For the sake of our patients, and the wonderful young people joining our amazing profession right now, I sure hope so. All together now: not too much, not too little.

Neal Maskrey’s early career was as a GP before spending seven years as a medical manager and part time GP. After 12 years as a director of the National Prescribing Centre and programme director at NICE, he is now honorary professor of evidence-informed decision making at Keele University, and consultant clinical adviser in the Medicines and Prescribing Centre, NICE.

Competing interests: I declare that I have read and understood the BMJ Group policy on declaration of interests and I hereby declare the following interest: Employed part time by the National Institute for Health and Care Excellence.