Constancy-Index

Short-term accuracy is expressed by the concept of constancy index. The principle is that the constancy index of the pump should be less than or equal to the half-life of the drug used.

The data from which the constancy index is calculated are derived from the flow tests performed over 24 hours at 1ml/h. Flow is recorded at 30 second intervals over the final 18 hour period. And the average rate is compared with flow over each observation window from 1,2,3,4,? 29,30 and 31 minutes.