Reliability and minimal detectable difference of pressure pain thresholds in a pain-free population
Ryan G. L. Koh, Tracy M. Paul, Karlo Nesovic, Daniel W. D. West, Dinesh Kumbhare, Richard D. Wilson
Abstract
The objective of this work was to evaluate the inter-rater and intra-rater reliability and minimal detectable difference (MDD) of pressure pain thresholds (PPTs) in pain-free participants with two examiners over two consecutive days in a cross-sectional study design. Examiners used a standardized method to measure and locate a specific testing site over tibialis anterior for PPT testing with a hand-held algometer. The mean of each examiner’s three PPT measurements was used to calculate the intraclass correlation coefficient, inter-rater reliability, and intra-rater reliability. The minimal detectable difference (MDD) was calculated. Eighteen participants were recruited (11 female). The inter-rater reliability was 0.94 and 0.96 on day 1 and day 2, respectively. Intra-rater reliability for the examiners was 0.96 and 0.92 on day 1 and day 2, respectively. The MDD on day 1 was 1.24 kg/cm 2 (CI: 0.76–2.03) and the MDD on day 2 was 0.88 kg/cm 2 (CI: 0.54–1.43). This study demonstrates high inter- and intra-rater reliability and the MDD values for this method of pressure algometry.