Reliability of pressure pain threshold testing in healthy pain free young adults

Abstract

Background and aims Investigation of the multidimensional correlates of pressure pain threshold (PPT) requires the study of large cohorts, and thus the use of multiple raters, for sufficient statistical power. Although PPT testing has previously been shown to be reliable, the reliability of multiple raters and investigation for systematic bias between raters has not been reported. The aim of this study was to evaluate the intrarater and interrater reliability of PPT measurement by handheld algometer at the wrist, leg, cervical spine and lumbar spine. Additionally the study aimed to calculate sample sizes required for parallel and cross-over studies for various effect sizes accounting for measurement error. Methods Five research assistants (RAs) each tested 20 pain free subjects at the wrist, leg, cervical and lumbar spine. Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and systematic bias were calculated. Results Both intrarater reliability (ICC = 0.81-0.99) and interrater reliability (ICC = 0.92-0.95) were excellent and intrarater SEM ranged from 79 to 100 kPa. There was systematic bias detected at three sites with no single rater tending to consistently rate higher or lower than others across all sites. Conclusion The excellent ICCs observed in this study support the utility of using multiple RAs in large cohort studies using standardised protocols, with the caveat that an absence of any confounding of study estimates by rater is checked, due to systematic rater bias identified in this study. Implications Thorough training of raters using PPT results in excellent interrater reliability. Clinical trials using PPT as an outcome measure should utilise a priori sample size calculations.

Alterations in Temporal Summation of Pain and Conditioned Pain Modulation Across an Episode of Experimental Exercise-Induced Low Back Pain

“…However, the magnitude of reduction is below previously reported minimum detectable change values for the trapezius and lower leg 69 . These small changes may therefore reflect slight localised peripheral sensitization due to repeated testing, as has been reported previously 48,59,68 , rather than a widespread effect of the exerciseinduced-LBP. Other mechanisms may be involved though, as PPTs at these sites have previously shown excellent reliability even with short testing intervals of 1-5 days 48,69 .…”

Exercise-induced hypoalgesia in women with varying levels of menstrual pain

“…Prior to study commencement, the assessors (SY, CC, ET, JN, RL) were formally trained in subject instruction and pressure algometer application for a total of 3 h over three occasions [27]. This included standardising their rate of pressure application, accurate land-marking of test sites, and applying pressure perpendicular to the skin.…”

“…The order of testing at the two sites was randomised. A standard script of instructions was read to each participant in accordance with Waller et al [27], with the participant asked to press the handheld button as soon as the sensation changed from pressure to uncomfortable to painful pressure. Since a total of four sets of measurements were taken at each site in a relatively short time-frame, only two repetitions were completed at each site and the average was extracted for analysis.…”

Investigation of the Effectiveness of Occlusal Splint, Acupuncture and Pharmacological Treatment in Myofascial Pain

“…Basınç ağrı eşiği ölçümü, miyofasiyal ağrı hastalarında tedavi etkinliğinin değerlendirilmesi açısından geçerli bir yöntem olarak literatürde yer bulmaktadır. [38][39][40][41][42][43][44] Bunun yanı sıra, farklı tedavi seçeneklerinin etkinliğinin karşılaştırılması amacıyla sıklıkla tercih edilmektedir. [45][46][47][48][49][50][51] Bu sebeplerle, parasetamol grubunda, çalışma sonuçlarında elde edilen basınç ağrı eşiği düşüşünün antiinflamatuar etki yaratmadan analjezi oluşturulması sonucu ağrı-spazm döngüsünü kırarak etki edilebileceği görülmektedir.…”