Methods are disclosed for measuring the size of body parts treated by a compression therapy device. Either the volume or circumference of the body part may be measured. The methods may include evacuating an inflatable compression sleeve to a known pressure, inserting the body part into the compression sleeve, inflating the sleeve to a pre-set condition, and then measuring one or more inflation related parameters. The pre-set conditions may include a pre-determined pressure, volume, or size of the inflatable cells comprising the sleeve. The inflation related parameters may include the time to fill the cell to a pre-set pressure, the pressure attained after a pre-set time of inflation, or the measured volume of a cell after a pre-set amount of air is introduced into it. The methods may also include deflating the cells from the known inflation state to a second inflation state and measuring similar parameters.
