This is an awesome tip that I learned from Dr. Ernestine Lee (who is also faculty here at Florida Hospital Family Medicine Residency). This tips was given as part of our "Learning Center" morning teaching which our faculty personally do for our residents. Enjoy!
In a busy practice, calculating the QTc (if your EKG machines doesn't do it for you) can be a chore. A quick way of estimating the normal QT interval is this:
The QT interval should be less than ½ the RR interval
This tips only works if the QRS complex is not widened. I haven't gone through the formal calculations yet to see how accurate this method is compared to directly calculating the QTc. But if sound logical since the QTc is the "corrected" QT interval which takes into consideration the RR interval. If someone does the calculations, please let me know! Cool!