Predictive value indicating positive test in a screening modality is calculated by:: (A) TP/TP+FP*100, (B) TN/TN+FN *100, (C) TP/TP+FN*100, (D) TN/FP+TN*100
Answer is A. Ans. (a) TP/TP+FP*100SENSITIVITYTP------TP+ FNx 100PREDICTIVE VALU OF A NEGATIVE TESTTN------TN+FNx 100SPECIFICITYTP------FP+ TNx 100% OF FALSE NEGATIVESFN------TP+ FNx 100PREDICTIVE VALU OF A POSITIVE TESTTP------TP+ FPx 100% OF FALSE POSITIVESTN------FP+ TNx 100