Batch/block correction

Correction of batch/block differences.

Usage

correctionCenter(d, block = "block", type = c("mean", "median"))

# S4 method for AnalysisData
correctionCenter(d, block = "block", type = c("mean", "median"))

Arguments

d

S4 object of class AnalysisData

block

sample information column name to use containing sample block groupings

type

type of average to use

Value

An S4 object of class AnalysisData containing the corrected data.

Details

There can sometimes be artificial batch related variability introduced into metabolomics analyses as a result of analytical instrumentation or sample preparation. With an appropriate randomised block design of sample injection order, batch related variability can be corrected using an average centring correction method of the individual features.

Methods

• correctionCenter: Correction using group average centring.

Examples

## Initial example data preparation
library(metaboData)

d <- analysisData(abr1$neg[,200:300],abr1$fact) %>% 
 occupancyMaximum(occupancy = 2/3)
 
## Group total ion count distributions prior to correction
d %>% 
 plotTIC(by = 'day',colour = 'day')

 
## Group total ion count distributions after group median correction
d %>% 
 correctionCenter(block = 'day',type = 'median') %>% 
 plotTIC(by = 'day',colour = 'day')