Comparison between the Visual Analogue Scale (VAS) and the Category Ratio Scale (CR-10) for the Evaluation of Leg Exertion

Abstract

Perceptual ratings given on the Visual Analogue Scale (VAS) and the Category Ratio Scale (CR-10) were compared in 24 healthy male volunteers (18-39 years) subjected to an exercise test using a bicycle ergometer. Ratings of leg exertion were made by means of the CR-10, the VAS and, as a complementary measure, the method of free magnitude estimation (ME). Blood lactate levels (BL) and heart rates (HR) were used as correlates to sensory perception. The correlation between the CR-10 ratings and BL at 180 W were .59 (p less than .01), and between VAS ratings and BL .45 (p less than .05). The corresponding correlations with HR were .64 (p less than 0.01) and .58 (p less than 0.01), respectively. No significant correlation was found for ME. It was concluded that both the CR-10 and the VAS scales were found to be useful for the psychophysical estimation of perceptual intensities. The CR-10 scale appeared to be slightly more efficient than the VAS and both these methods much better than ME. The advantage of the CR-10 scale might be due to a greater ability to discriminate at high intensity levels.

Assessment of Muscle Pain Induced by Elbow-Flexor Eccentric Exercise

“…subjectively during exercise exertion. 16,32 The changes in MVIC, ROM, and serum CK activity after eccentric exercise in our study were similar to those reported in previous studies 22,33 and indicate that muscle damage was induced by the exercise. The time course of the changes in VAS score and PPT was also similar to those reported after eccentric elbow-flexor exercise in previous research.…”

“…The level of muscle pain evoked by the standardized stimulus was assessed using a 100-mm VAS on which 0 indicated no pain and 100 represented extreme pain 28 and a CR-10 scale on which 0 indicated no pain and 10 represented maximal pain. 15,16 Each participant was asked to mark the level of perceived pain on the VAS, followed by the CR-10 scale (the 2 assessments were performed consecutively), when the investigator applied pressure to the biceps brachii at 3, 9, and 15 cm above the elbow crease. During the pressure assessment, the investigator placed his index and middle fingers over the site and applied pressure (approximately 35-40 kPa or 250 mm Hg) with the tips of the fingers toward the deeper tissues for 3 seconds.…”

“…15,16 Concerns similar to those regarding stimulus standardization exist for these scales when the level of muscle pain is assessed on palpation or with other mechanical stimuli. To the best of our knowledge, no previous authors have compared a VAS and CR-10 scale for the same mechanical stimuli, and no consensus has emerged as to which is better.…”

“…Instead of VASs, some researchers used numerical rating instruments such as Likert 14 or category ratio-10 (CR-10) scales 15,16 to quantify the muscle-pain level, and the CR-10 scale is often used to quantify the pain level during exercise exertion. 15,16 Concerns similar to those regarding stimulus standardization exist for these scales when the level of muscle pain is assessed on palpation or with other mechanical stimuli.…”

On perceived exertion and its measurement

“…This has, however, been met with criticism, as has the assumption of congruence in meaning of scale values (Svensson, 1998(Svensson, , 2000Williams, Davies and Chadury, 2000). The VAS has also been found to be subject to end effects (Neely, Ljunggren, Sylvén and G. Borg, 1992;Neely and E. Borg, 1995).…”