Publicly Insured

This article dealt with doctors refusing to make appointments to publicly insured child patients. Two out of three publicly insured child patients were refused an appointment while only eleven percent of privately insured child patients were refused. Publicly insured patients who were given an appointment also had to wait an average of forty two days compared to privately insured patients who waited an average of twenty two days for an appointment.

Is it against "doctor code" to deny a patient treatment and/or attention based on whether or not they are privately insured?