In the app, what is the difference between an “Extra reading” and an “AM reading” or “PM reading”?

BPCorrect has been carefully designed to guide users to adhere to the American Heart Association’s recommended schedule of twice daily blood pressure measurements (two readings, taken one minute apart, every AM and PM). BPCorrect defines AM readings as the first two readings taken between 4 AM and noon, and PM readings as the first two readings taken between 4 PM and midnight. While additional AM or PM readings beyond the first two readings or readings taken outside of this time range are displayed in the app, they are labeled as “Extra readings.” To avoid skewing the average, these “extra” blood pressure readings are excluded from the calculation of the average blood pressure.