What are the guidelines used to determine if a diabetic is Type 1 or Type 2? I realize there are blood tests that can be done but what if doing phone screening for a diabetes study?

The most accurate phone screening information would be a history of symptoms of weight loss and ketones in the urine prior to the diagnosis of diabetes establishing the diagnosis of Type 1. If the person wasn’t overweight and was a child or teenager at diagnosis, the individual most likely had type 1. After the teenage years, the onset of type 1 diabetes can be slow and someone can be diagnosed in the early phases of high blood sugar, without ketones and weight loss. The younger the person, the more likely this is type 1 diabetes, but as you get into the 30’s and 40’s, there is considerable overlap in the clinical presentation. If the person was over 40 and overweight when diagnosed, most likely the person has Type 2.

TGL