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.

                                                                       NRS <3 - mild pruritus
                                                                       NRS  >  3< 7 - moderate Pruritus
                                                                       NRS > 7< 9 - severe Pruritus
                                                                       NRS > 9 - very severy pruritus
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.
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  • 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.