A computer system for the numerical analysis of nonstress tests

The development and clinical validation of a computer system for the numerical analysis of nonstress tests is reviewed, and recent improvements are reported. The analysis was developed by using a database of 73,802 nonstress test readings to provide a numerical definition of reactivity that is tailored to the gestational age of the fetus and independent of the presence of accelerations. When used at the bedside, the analysis minimizes monitoring time by alerting the operator when monitoring can be safely stopped because the fetal heart rate is normal. It also detects potentially sinister sinusoidal patterns and improves the quality of nonstress test readings by quantifying signal loss and, if significant, alerting the operator. (Am J Obstet Gynecol 2002;186:1095-1103.)