The Bodystat 1500 works by passing a safe, battery-generated signal through the body, measuring impedence. The patient's gender, age, height, weight, activity level and waist/hip measurements are entered using the simple keypad. Once the test has been performed, a complete body composition analysis is displayed on the LCD screen within three seconds. The analysis is comprised of Body Fat, Lean Body Mass and Total Body Water compared to optimal ranges. Metabolic rates and BMI are also calculated.