The debate over the Affordable Care Act has persisted since its enactment in 2010, and has high visibility in the current U.S. presidential election campaign as well. Affordability and patient access to health care have been among the main issues. New research at Wharton and the University of Pennsylvania finds that narrow networks come with lower premiums. But they come with tradeoffs and unpleasant surprises such as not being able to find the right doctor in your network, or having to pay more for care, or not being able to get appointments quickly enough. Compounding those hurdles are exits by insurers that have incurred losses in several markets. Insurers that have succeeded are those that know how best to operate in their markets, says Daniel Polsky , the study’s co-author and Wharton professor of health care management.…