Here is an interesting and informative article on private supplemental healthcare in the UK.
For example, one GP told me that he tries hard not to obtain specialty consultations unless absolutely necessary, as a matter of pride and " to a degree " economics (each primary care network has a global budget that covers only so many specialty consultations). But there is a subtler disincentive for GPs to obtain consults: specialists, salaried and often overwhelmingly busy, can be nasty. "I'll send an NHS patient to an orthopedic surgeon," this GP told me, "and I'll get back a letter from the consultant. What it says is civil enough. But between the lines, its message is: How could you be so stupid that you couldn't manage this patient yourself?'"
Anyone who has ever seen a harried cardiology fellow attack an intern for a "lame consult" may not be surprised by this behavior from an overworked consultant who lacks any economic incentive to see the next patient. But things are different when the patient has private insurance. Suddenly, the threshold for consultation is much lower, the consults aren't scrutinized by anyone (since the payment comes from the insurer, not the NHS or the practice), and the consultant is tickled pink to see the patient and pocket the generous fee " and sings a very different tune to the referring doctor. "When I send a private patient to the very same orthopedic surgeon," the GP told me, chuckling, "I get a very different type of letter back. It might say, You were brilliant to send this patient to me. I so look forward to managing this patient with you.' Doesn't the surgeon realize I'm the same person?"
The conflicts play out within the specialists' practices themselves. One London neurologist told me that he might see a patient in consultation for a neurological disorder and offer a follow-up appointment in several months, assuming there is no urgent clinical need. "But if the patient has private insurance, she can see me tomorrow if she'd like."
The average specialist in the UK augments his or her income by about 50 percent through private practice, but there are wide variations. Specialists operating in the countryside, where few patients have private insurance, may have no opportunity to practice privately. On the other hand, some London specialists double or triple their salaries through private work. I asked several prominent specialists why they didn't just ditch the NHS and switch to full-time private practice. The answers varied, but usually included some version of "I take my obligation to participate in the NHS seriously" (this may sound a bit too idealistic for jaded Americans, but I found this credible in the UK, where belief in the NHS can be near-religious) and, more pragmatically, "It is my NHS practice that allows me to be prominent enough to attract patients to my private practice."