The influence of slope calculation method on the reliability of near-infrared spectroscopy parameters during a vascular occlusion test : research data underlying the article

Iskra, Simon (author), Turnšek, Gašper (author), Paravlić, Armin (author)

Aim: To assess within and between-day reliability of near-infrared spectroscopy derived measures of microvascular function during a vascular occlusion test (VOT), to assess whether different methods for slope calculation and blood volume correction improve reliability. Methods: Twenty-three healthy adults (11 males, 12 females) completed three laboratory visits, during which a VOT was performed using a continuous-wave NIRS device on the forearm. Reoxygenation (reoxyslope) and deoxygenation (deoxyslope) slopes along with muscle oxygen uptake (mVO2) were calculated using a fixed 10-s average, as well as maximal 3- and 1-s rolling averages for reoxygenation and average, 30-s and 10-s rolling average for deoxygenation parameters. Additionally, mVO2 was corrected for blood volume change (mVO2corr). Intraclass correlation coefficients were used to determine the within- and between-day reliability of selected measures. Results: There were no differences in within- or between-day reliability for different methods of calculation of selected parameters. However, significantly higher values were observed when shorter time window was used. In general, the parameters exhibited moderate to good within- and poor to moderate between-day reliability. Blood volume correction improved reliability of mVO2 values. Linear mixed model analysis revealed sex as a significant predictor of reoxyslope and mVO2corr, with males exhibiting slower reoxyslope and higher mVO2corr. Conclusion: The slope calculation method significantly influences the values obtained during VOT, while their reliability remains unchanged. The use of a blood volume correction is warranted and data quality reporting in future studies seems warranted. Significant sex differences were observed, highlighting the different mechanism regulating microvascular function during VOT.

• Language: English
• Keywords: near-infrared spectroscopy, vascular occlusion test, reliability, microvascular reactivity
• Typology: 2.20 - Complete scientific database of research data
• Organization: FŠ - Faculty of Sport
• Year: 2026
• PID: 20.500.12556/RUL-188022
• Data col. methods: Experiment
• Publication date in RUL: 17.09.2026

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: bližnje infrardeča spektroskopija, test žilne okluzije, zanesljivost, mikrovaskularna reaktivnost