Using the Numeric Rating Scale for measurement of nipple pain in research

A Numeric Rating Scale for pain (NRS) renders a quantitative symbolization of an attribute or experience. It is typically a scale of numbers from 0-10 (or sometimes 0-100) from which the participant chooses to best reflect their pain experience, with 0 as no pain and 10 as maximum possible pain experience.

A Visual Analogue Scale for pain (VAS) renders this same quantitative symbolization on a written or digital image of a scale from 0-10.

A 2018 systematic review of measurement tools and intensity of nipple pain among women with or without damage to the nipples included 25 selected studies. Analysis of these studies concluded that the Numeric Rating Scale (NRS) and the Visual Analogue Scale (VAS) were most commonly used for assessment of nipple pain in lactating women, and that these two scales showed equivalent results. Nine of these studies applied the NRS.7

Using a pain score between 0-10, either on the NRS or the VAS, women with nipple damage reported a weighted mean of 6.2 in the first week and 5.8 after that period; women without damage but experiencing pain reported a weighted mean of 2.7.

Using the Numerica Rating Scale for measurement of nipple pain in the clinic

In the gestalt method, we use the Numeric Rating Scale, because micromovement work in the clinic, with the clinicians hands placed upon and support the breastfeeding woman's forearm, is dynamic. Women give the clinician a number on the NRS that best correlates with their pain experience, and the clinician regularly requests feedback on this scale as they work together, applying micromovements in the three directions. The NRS is used to indicate how best to calibrate micro-movements so that breast tissue drag and corresponding pain can be minimised.

At the same time, we acknowledge that not all women like to work in numbers, and so we may just work with "let's try a millimetre or two more in this direction - is that better, or is that worse?"

References

Coca KP, Amir LH, Da Silva Alves MdR, Barbieri M, Marcacine KO, De Vilhena Abrao ACF. Measurement tools and intensity of nipple pain among women with or without damaged nipples: a quantitative systematic review. Journal of Advanced Nursing. 2018;75:1162-1172.