10FoldCV	repeated 10-fold cross validation
ACN	acetonitrile
AUC	accuracy
BC	bladder cancer
BHP	benign prostate hypertrophy
CI	confidence interval
DDLLME	dispersive derivatisation liquid–liquid microextraction
DMF	dimethylformamide
DoubleCV	double cross validation
DRE	digital rectal examination
EN	electronic nose
ESI	electrospray ionisation
GC-MS	gas chromatography-mass spectrometry
GS	Gleason score
LC-MS	liquid chromatography-mass spectrometry
LDA	linear discriminant analysis
LOOCV	leave one out cross validation
MAD	microwave assisted derivatisation
MOS	metal oxide semiconductors
PBs	transrectal ultrasound-guided prostate biopsy
PCa	prostate cancer
PCA	principal component analysis
PLS-DA	partial least squares discriminant analysis
PSA	prostate specific antigen
Put	putrescine
RF	random forest
ROC	receiver operating characteristics
Spd	spermidine
Spm	spermine
SPME	solid phase microextraction
SVM	support vector machine
SVM-P	Support vector machine-polynomial
UPLC	ultra-high performance liquid chromatography
VOCs	volatile organic compounds