npi {genefu} | R Documentation

## Function to compute the Nottingham Prognostic Index

### Description

This function computes the Nottingham Prognostic Index (NPI) as published in Galeat et al, 1992. NPI is a clinical index shown to be highly prognostic in breast cancer.

### Usage

    npi(size, grade, node, na.rm = FALSE)

### Arguments

`size` | tumor size in cm.
`grade` | Histological grade, i.e. low (1), intermediate (2) and high (3) grade.
`node` | Nodal status. If only binary nodal status (0/1) is available, map 0 to 1 and 1 to 3.
`na.rm` | TRUE if missing values should be removed, FALSE otherwise.

### Details

The risk prediction is either Good if score < 3.4, Intermediate if 3.4 <= score <- 5.4, or Poor if score > 5.4.

### Value

A list with items:

- score: Continuous signature scores

- risk: Binary risk classification, 1 being high risk and 0 being low risk.

### References

Galea MH, Blamey RW, Elston CE, and Ellis IO (1992) "The nottingham prognostic index in primary breast cancer", Breast Cancer Reasearch and Treatment, 22(3):207-219.

### See Also

st.gallen

### Examples

    # load NKI dataset
    data(nkis)
    # compute NPI score and risk classification
    npi(size=demo.nkis[ ,"size"], grade=demo.nkis[ ,"grade"],
      node=ifelse(demo.nkis[ ,"node"] == 0, 1, 3), na.rm=TRUE)

[Package genefu version 2.24.2 Index]