Which plan type, e.g. PPO, HMO, etc. is more likely to offer me a higher and stable price for services?

HMOs still generate more income than PPOs do. The median percentage of gross income from capitation increased for FPs, internists, and ob/gyns, dropped for GPs, and remained the same for pediatricians.

The strength of capitation in some markets—coupled with the sheer size of some plans—explains much of the continued dominance of HMOs in primary care income. It’s possible that competition with increasingly popular PPOs has caused some HMOs to shift their emphasis from capitation to fee-for-service.