Table 1 Hypothetical research scenario

Let’s pretend that researchers want to find ways to help people who are having trouble managing their diabetes to be more successful. They want to see whether people who receive a daily telephone call reminding them to check their blood sugar levels will do a better job of keeping their blood sugar at healthy levels. They want to conduct a study with patients who have diabetes and agree to be in the study to determine if the telephone reminders actually work. Half of the patients in the study would receive a daily phone call reminder to check their blood sugar. The other half of the patients would not receive the call. The researchers would keep track of all of the patients’ blood sugar levels over a 3 month period to see whether patients who got phone calls were managing their blood sugar better than patients who were not getting calls.

In order to conduct the study, the researchers first need to identify people with diabetes who they can invite to be in the study. To find people with diabetes, the researchers use a computer program to search through thousands of EHRs. They create a search that tells the computer to pull EHRs based on diagnostic codes, lab results, and medications that may indicate that someone has diabetes. The computer runs the search, which provides the researchers with the EHRs of patients who likely have diabetes, and thus, might be eligible to be in the study.