Identify Itch Intensity

The main goal of conducting an assessment of pruritus is to determine its intensity. Here are different instruments are available. The most common tools are the "Visual Analog Scale (VAS)", the Numerical Rating Scale (NRS)" and the Verbal Rating Scale (VRS)" These are monodimensional scales, which measure the subjective intensity of pruritus at a certain time.

Numerical Rating scale (NRS)

The NRS is comprised of one item and represents the numbers 0 (“no itch”) to 10 (“worst imaginable itch”). Subjects are asked to rate the intensity of their itch using this scale. It features high reliability and concurrent validity and is a popular choice for all patients due to its simple format.

Time needed for completion: 1 minute
Validated in English, French, German, Italian, Polish, Russian, Spanish and Turkish (click to download)
Also available in Japanese and Czech (click to download)
It can be interpreted as follows:
- NRS 0 = no pruritus
- NRS <3 = mild pruritus
- NRS ≥3 <7 = moderate Pruritus
- NRS ≥7 <9 = severe Pruritus
- NRS ≥9 = very severy pruritus

Visual Analogue Scale (VAS)

The VAS is a scale consisting of a 10cm long line and a single question. Along with the NRS, it is most commonly used in clinical trials for measuring itch intensity and features high reliability and concurrent validity. The left end point represents “no itch” and the right end point the “worst imaginable itch”.

It can be interpreted as follows:
- VAS 0 = no pruritus
- VAS < 3 = mild pruritus
- VAS ≥3<7 = moderate pruritus
- VAS ≥7<9 = severe pruritus
- VAS ≥9 = very severe pruritus
Time needed for completion: 1 minute
Validated in English, French, German, Italian, Polish, Russian, Spanish and Turkish (click to download)

Verbal Rating Scale (VRS)

The VRS is a five-point scale and consists of a list of adjectives describing various levels of symptom intensity (0 = no itch, 1 = mild itch, 2 = moderate itch, 3 = severe itch and 4 = very severe itch). It is used to categorize the itch intensity and features high reliability and concurrent validity.

Currently validated in English, French, German, Italian, Polish, Russian, Spanish and Turkish (click to download)

References

Verweyen E, Ständer S, Kreitz K, Höben I, Osada N, Gernart M, Riepe C, Pereira M, Blome C, Augustin M, Zeidler C. Validation of a Comprehensive Set of Pruritus Assessment Instruments: The Chronic Pruritus Tools Questionnaire PRURITOOLS. Acta Derm Venereol. 2019 Mar 5.
Reich A, Chatzigeorkidis E, Zeidler C, Osada N, Furue M, Takamori K, Ebata T, Augustin M, Szepietowski JC, Ständer S. Tailoring the Cut-off Values of the Visual Analogue Scale and Numeric Rating Scale in Itch Assessment. Acta Derm Venereol. 2017 Jun 9;97(6):759–760.
Reich A, Riepe C, Anastasiadou Z, M?drek K, Augustin M, Szepietowski JC, Ständer S. Itch assessment with visual analogue scale and numerical rating scale: determination of minimal clinically important difference in chronic itch. Acta Derm Venereol 2016; 96: 978–980.
Phan NQ, Blome C, Fritz F, Gerss J, Reich A, Ebata T, et al. Assessment of pruritus intensity: prospective study on validity and reliability of the visual analogue scale, numerical rating scale and verbal rating scale in 471 patients with chronic pruritus. Acta Derm Venereol 2012; 92: 502–507.
Storck M, Sandmann S, Bruland P, Pereira MP, Steinke S, Riepe C, Soto-Rey I, Garcovich S, Augustin M, Blome C, Bobko S, Legat FJ, Potekaev N, Lvov A, Misery L, Weger W, Reich A, Şavk E, Streit M, Serra-Baldrich E, Szepietowski JC, Dugas M, Ständer S, Zeidler C. Pruritus Intensity Scales across Europe: A Prospective Validation Study. J Eur Acad Dermatol Venereol. 2021 Jan 7.
Reich A, Chatzigeorkidis E, Zeidler C, Osada N, Furue M, Takamori K, Ebata T, Augustin M, Szepietowski JC, Ständer S. Tailoring the Cut-off Values of the Visual Analogue Scale and Numeric Rating Scale in Itch Assessment. Acta Derm Venereol. 2017 Jun 9;97(6):759-760.
Reich A, Riepe C, Anastasiadou Z, M?drek K, Augustin M, Szepietowski JC, Ständer S. Itch assessment with visual analogue scale and numerical rating scale: determination of minimal clinically important difference in chronic itch. Acta Derm Venereol 2016; 96: 978–980.
Kido-Nakahara M, Katoh N, Saeki H, Mizutani H, Hagihara A, Takeuchi S, et al. Comparative cut-off value setting of pruritus intensity in visual analogue scale and verbal rating scale. Acta Derm Venereol 2015; 95: 345–346.
Furue M, Ebata T, Ikoma A, Takeuchi S, Kataoka Y, Takamori K, et al. Verbalizing extremes of the visual analogue scale for pruritus: a consensus statement. Acta Derm Venereol 2013; 93: 214–215.
Phan NQ, Blome C, Fritz F, Gerss J, Reich A, Ebata T, et al. Assessment of pruritus intensity: prospective study on validity and reliability of the visual analogue scale, numerical rating scale and verbal rating scale in 471 patients with chronic pruritus. Acta Derm Venereol 2012; 92: 502–507.
Reich A, Heisig M, Phan NQ, Taneda K, Takamori K, Takeuchi S, et al. Visual analogue scale: evaluation of the instrument for the assessment of pruritus. Acta Derm Venereol 2012; 92: 497–50.
Storck M, Sandmann S, Bruland P, Pereira MP, Steinke S, Riepe C, Soto-Rey I, Garcovich S, Augustin M, Blome C, Bobko S, Legat FJ, Potekaev N, Lvov A, Misery L, Weger W, Reich A, Şavk E, Streit M, Serra-Baldrich E, Szepietowski JC, Dugas M, Ständer S, Zeidler C. Pruritus Intensity Scales across Europe: A Prospective Validation Study. J Eur Acad Dermatol Venereol. 2021 Jan 7.
Kido-Nakahara M, Katoh N, Saeki H, Mizutani H, Hagihara A, Takeuchi S, et al. Comparative cut-off value setting of pruritus intensity in visual analogue scale and verbal rating scale. Acta Derm Venereol 2015; 95: 345–346.
Phan NQ, Blome C, Fritz F, Gerss J, Reich A, Ebata T, et al. Assessment of pruritus intensity: prospective study on validity and reliability of the visual analogue scale, numerical rating scale and verbal rating scale in 471 patients with chronic pruritus. Acta Derm Venereol 2012; 92: 502–507.
Storck M, Sandmann S, Bruland P, Pereira MP, Steinke S, Riepe C, Soto-Rey I, Garcovich S, Augustin M, Blome C, Bobko S, Legat FJ, Potekaev N, Lvov A, Misery L, Weger W, Reich A, Şavk E, Streit M, Serra-Baldrich E, Szepietowski JC, Dugas M, Ständer S, Zeidler C. Pruritus Intensity Scales across Europe: A Prospective Validation Study. J Eur Acad Dermatol Venereol. 2021 Jan 7.