Table 3 Comparative analysis of the current study results with state-of-the-art pain level classifications.

From: Pain classification using functional near infrared spectroscopy and assessment of virtual reality effects in cancer pain management

Study

Year

Data

Pain source

Subjects

Samples

Number of classes

Model

Test samples

Accuracy (%)

Rojas et al.83

2021

fNIRS

Thermal pain perceptions

18 healthy subjects

300

2 (cold and hot induced pain)

Deep learning (bidirectional long short-term memory)

30% of randomly selected samples

90.6

Fernandez Rojas et al.47

2017

fNIRS

Thermal pain perceptions

18 healthy subjects

352

2 (cold and hot induced pain)

k-nearest neighborhood

Data from 5 subjects

92.08

Lopez-Martinez et al.14

2019

fNIRS

Electrical noxious stimuli and tactile brush stimuli

43 healthy participants

43

2 (no pain and pain)

Support Vector Machine (rbf kernel)

10% of randomly selected sampled

69

Current study

2025

fNIRS

Cancer-related pain

93 cancer patients and 13 healthy participants

129

3 (no or mild pain, moderate pain, severe pain)

Multinomial logistic regression

129 test samples obtained by applying leave-one-participant-out cross validation

74