Background & Aims

Quantitative sensory testing (QST) is a detailed form of sensory examination used to aid characterization and diagnosis in pain conditions. Since it is a type of psychophysical testing, there are several potential sources of bias and error that can impact reliability. To minimize this, standardized testing with scripted instructions and specific training have been introduced, for example by the German Research Network on Neuropathic Pain (DFNS) [1]. A small number of studies have demonstrated good inter-, intra-rater and test re-test reliability [2,3], mainly in the German language. For the protocol to be used in different languages, it must undergo a robust process for translation, for example into the Thai language [4]. To improve confidence in newly translated versions used in novel settings, reliability should be demonstrated in healthy volunteers.

Aim: To identify the reliability of a translated standardized QST protocol in a Thai healthy volunteer cohort.

Methods

Validation of a Thai version of the standardized DFNS QST instruction was performed according to the WHO guideline for translation and adaptation of instruments [4]. Healthy volunteers underwent the full QST protocol at four body sites (dorsum of both hands and feet). Testing was repeated after 7-10 days. All testing was completed by a single, formally trained assessor (SN) using recommended equipment (including TSA-II NeuroSensory Analyzer thermal stimulator (Medoc Ltd, Israel); PinPrick Stimulators and OptiHair2 von Frey filaments (MRC Systems, Germany)). Only those meeting published criteria for healthy volunteers [5] were included. Intra-rater reliability using results from two body sites within a single session, and test-retest reliability between sessions were calculated using intraclass correlations (ICC, two-way mixed effect model, absolute agreement). ICC of 0.4-0.59 was defined as ‘fair’ reliability, 0.6-0.75 as ‘good’ and >0.75 as ‘excellent’ [6].

Results

Thirty volunteers were recruited (n=15 male, mean age 34.6(12.3) years). Pressure pain threshold and mechanical pain sensitivity demonstrated excellent intra-rater reliability (ICC PPT=0.78-0.91; MPS=0.87-0.94). Mechanical detection demonstrated good reliability (ICC 0.62-0.74). Intra-rater reliability of thermal detection thresholds was less robust, ranging from poor-fair in the feet (0.24-0.67) to fair in the hands (0.41-0.58). Intra-rater reliability was higher in the second session for 14/22 measures.

Test-retest reliability at both hands and feet was excellent for PPT and MPS (ICC PPT=0.79-0.80; MPS=0.77-0.78), good for thermal pain thresholds, and fair for mechanical pain threshold. However, cold detection threshold (CDT) demonstrated only poor reliability in the feet (0.30) and fair reliability in the hands (0.47). Other parameters ranged from poor to good, but test-retest reliability tended to be more robust in the hands.

Conclusions

When compared to other studies of the reliability of the DFNS protocol and other QST protocols, similar patterns were seen. For example, thermal detection is known to demonstrate poor-fair test-retest reliability over time in healthy volunteers, whereas heat pain thresholds are more reliable [2,3]. Our results demonstrate better reliability for PPT than some studies which may be a result of a shorter inter-test interval [3,7]. The influence of body site has also been previously reported with the hand exhibiting slightly more robust reliability than other areas [3]. The second test session showed higher intra-rater reliability in more parameters which could suggest an element of learning or familiarity on the part of the participant or tester.

The Thai instruction for standardized QST demonstrates acceptable intra-rater and test-retest reliability in a healthy cohort. The variation in reliability between test parameters and body sites was similar to studies in other world regions.

References

1.Rolke et al. (2006) Quantitative sensory testing: a comprehensive protocol for clinical trials. Eur J Pain 10:77-88.
2.Geber et al. (2011) Test-retest and interobserver reliability of quantitative sensory testing according to the protocol of the German Research Network on Neuropathic Pain (DFNS): a multi-centre study. PAIN 152: 548-56
3.Nothnagel et al. (2017) How stable are quantitative sensory testing measurements over time? Report on 10-week reliability and agreement of results in healthy volunteers. J Pain Res 10: 2067-78
4.Niruthisard et al. (2021) Standardized quantitative sensory testing for reference values in healthy adult Thai volunteers. Poster presentation at the IASP World Congress 2021.
5.Gierthmühlen et al. (2015) Who is healthy? Aspects to consider when including healthy volunteers in QST–based studies-a consensus statement by the EUROPAIN and NEUROPAIN consortia. PAIN 156:2203-11.
6.Shrout & Fleiss (1979) Intraclass correlations: Uses in assessing rate reliability. Psychol Bulletin 86:420-8.
7.Walton et al. (2014) Clinical pressure pain threshold testing in neck pain: comparing protocols, responsiveness, and association with psychological variables. Phys Ther 94:827–37

Presenting Author

Harriet Kemp

Poster Authors

Harriet Kemp, MD

BM BCh PhD

Imperial College London

Lead Author

PATT PANNANGPETCH

Department of Anesthesiology, Pain Management Research Unit, Chulalongkorn University, Thailand

Lead Author

Yuda Chongpison

Biostatistics Excellence Centre, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand

Lead Author

Jan Vollert

University of Exeter

Lead Author

Walter Magerl

Mannheim Center for translational neurosciences, Heidelberg University, Mannheim, Germany

Lead Author

Pornpan Chalermkitpanit

Dept Anesthesiology, Chulalongkorn University & King Chulalongkorn Memorial Hospital, Thailand

Lead Author

marvin thepsoparn

Dept Anesthesiology, Chulalongkorn University & King Chulalongkorn Memorial Hospital, Thailand

Lead Author

Pin Sriprajittichai

Dept Anesthesiology, Chulalongkorn University & King Chulalongkorn Memorial Hospital, Thailand

Lead Author

Pakorn Urusopone

Department of Anesthesiology, King Chulalongkorn Memorial Hospital, Bangkok, Thailand

Lead Author

Jakkrit Amornvit

Division of Neurology, Dept of Medicine, King Chulalongkorn Memorial Hospital, Bangkok, Thailand

Lead Author

Andrew Rice

Imperial College London

Lead Author

Rolf-Detlef Treede

Heidelberg University

Lead Author

Supranee Niruthisard

Department of Anesthesiology, King Chulalongkorn Memorial Hospital, Bangkok, Thailand

Lead Author

Topics

  • Assessment and Diagnosis