Final answer:
Consolidation of purchasers through Managed Care Organizations (MCOs) was not a characteristic of medical service in the corporate era; instead, there was consolidation of providers and a shift towards HMOs.
Step-by-step explanation:
The characteristic that was NOT a feature of medical service in the corporate era is the consolidation of purchasers (MCOs). During this period, various transformations occurred in the healthcare system, including the movement from a fee-for-service model to an emphasis on Health Maintenance Organizations (HMOs).
Growth in consolidation was observed among providers, not purchasers, with hospital 'merger mania' leading to smaller practices being absorbed by larger health systems. While there was a focus on mass production and efficiency, along with the expansion of urgent care offices and telemedicine, the shift in reimbursement models to a mix of managed care and fee-for-service aimed at reducing moral hazard by incentivizing providers to limit unnecessary services was also notable. The consolidation of purchasers through Managed Care Organizations (MCOs) was not highlighted as a characteristic of medical service provision during the corporate era.