Standardization

The underlying reason for the discrepancy in quality of care is the lack of standardization. There isn't enough regulation of services to standardize when services should and should not be provided. Sadly, the closest we get to a regulating body is insurance companies, who at least stipulate when services should not be provided because they are not proven to be of benefit (the the insurer's pocket book rather than the the insured's health... but still). 

Additionally, this is not always an issue of access. Each doctor has their own guidelines and this contributed to why so many patients have such a hard time trusting their doctor, after all another doctor may tell them something different. 

We need a governing body that closely regulates the provision of services to all patients, whether insured or not, to advocate for patient health. Therefore doctors that fail to provide necessary services and doctors that provide unnecessary services will be watched over more closely. Rather than punishing doctors we need to provide incentives for a higher standard of care.