The uninsured tended to be prescribed more generic medications:

According to the survey, 88 percent of the doctors made at least one change in their patients’ clinical management due to his or her insurance status. Overall, physicians changed management strategies for 99 of 409 patients. Nearly two-thirds (62.6 percent) of the time, doctors discussed insurance issues with patients and made changes based on insurance status.

Common changes in practice included prescribing two separate generic medicines instead of one brand-name combination pill, or using a less expensive but longer course of medication. Both strategies make it more likely that a patient will not keep up with the prescribed regimen, the researchers noted.