The range rule tells us that the standard deviation of a sample is approximately equal to one fourth of the range of the data. In other words s = (Maximum â Minimum)/4. This is a very straightforward formula to use, and should only be used as a very rough estimate of the standard deviation.
4) Durable medical equipment: Wheel chair, commodes and raised toilet sheet, walker and power operated vehicles which improves the quality of living of the patients are known as durable medical equipment. It also includes iron lungs, oxygen tents, nebulizers, catheters and hospital beds.
The durable medical equipment, like power chairs, wheel chairs and oxygen, must be prescribed to be used in your home. You generally arenât ârequiredâ to have the equipment if it is only to be used when you leave your home.