How do we measure pain? And is your pain worse than someone else’s?
As we’ve highlighted in previous articles, in our initial consultations with people we ask a lot of questions….sometimes we ask the same question in different ways to try to get consistent information about a person’s symptoms and why they may be occurring. One of the questions we always ask is ‘On a scale of 1 – 10, how severe is your pain?’. People often find this a very difficult question to answer as the initial reaction from most people is to want to quantify what constitutes a 10/10, and is their 10 the same as someone else’s 10? Often people will not be able to give an actual figure and will try to explain it in another way, such as ‘It’s not as bad as when I broke my leg, but still very sore’. What we hope to do in this short post is to explain why we ask this simple but awkward question, and what it tells us.
When assessing a person for pain what we are trying to do is understand what is causing a person’s symptoms, given that pain is a ‘lived’ experience it is something that can only be described to another person. A common way of doing this is to follow a checklist that includes the following characteristics;
- Location
- A description of the sensation
- Intensity
- Duration
- Frequency
- Pattern
All of these characteristics give us clues to what might be causing a person’s pain, the measure of intensity is an important part of that process. Pain is, of course, subjective, one person’s 7/10 might be another’s 3/10, but getting people to score their pain numerically gives us a snapshot in time of that person’s experience at that time, we will use this measure to not only give us insight into the cause of a person’s symptoms but also how their symptoms might be changing (1). This helps inform us about how effective their treatment is and how long it may take.
The numerical pain rating scale (NPRS) of 1 – 10 may seem like a very crude tool, and that a more advanced method of assessment such as this or this would be superior, but there is a surprisingly large amount of research that supports the NRS’s acceptability (2), reliability and validity (3) across a number of disciplines. Not only that but the nature of the scale means that it can be administered verbally which makes it applicable for those who lack literacy or English reading skills and for use in telephone consultations
One thing we have to keep in mind is that several factors can influence a person’s reported NRPS score, for instance, people with depression tend to have higher reported pain scores (5). This is thought to be due to a person’s depressive state changing how they view pain, commonly it is found that people with depression will focus attention on negative pain sensations and this can result in catastrophizing the situation and reporting higher pain levels. . There is also good evidence that a 2 point change in the NPRS relates to a clinical change in a person’s symptoms meaning it is a useful tool to measure a person’s progress from treatment (4).
It has also been observed that people who have a strong history of opioid medication can develop a condition known as opioid induced hyperalgesia, this paradoxical state is when a person has been taking opioid medication for a period of time and has resulted in changes in how the nervous system reports pain making the person more likely report a higher pain intensity score (6).
Age will also play a part, chronic pain is more prevalent as we get older, and tends to level off when we get to 65 (7). However, older people are more likely to report a higher pain score for the same experimentally induced stimulus (heat in this case) than younger people and are more likely to relate their pain to their health status (8).
At this point it would be suitable to bring up the differences in pain severity reporting between men and women, the anecdotal temptation is to assume that women have a higher pain threshold than men, however in measures of pain post-surgery, and experimentally induced pain, women tend to score their pain higher than men (9). A few reasons may be responsible for this, firstly the biochemical differences between the sexes, men tend to have higher levels of testosterone which may have a pain limiting effect (10) and the hormonal change during menstruation makes women report higher levels of pain (11). Other factors that may explain this are psychosocial in nature, basically that men and women address the experience of pain differently. Men tend to use behavioral distraction techniques to deal with pain, whereas women tend to use techniques of attentional focus, these difference may result in a difference in how they report pain (12). Research also shows that social and cultural beliefs influence a person’s pain score, with both men and women believing that it is more culturally acceptable for women to report pain, this may produce a bias in how pain is recorded (13). (Semi-serious note – we are in no way saying that women are less able to cope with pain, just that there are differences in how they report it. Our anecdotal experience is that women tend to be more pragmatic and tolerant of their pain than men.)
Although it only makes up a small part of our assessment, we find that measuring pain intensity in the people we treat as being very useful. As you can see a scale of 1 – 10 may seem simplistic but with the correct interpretation and applying context to the score, it does in fact give us a lot of reliable information to help us treat your symptoms!
Do you want to know what is causing your pain and if we can help? Why not take advantage of our new patient assessment introductory offer to get you started towards a tailor made recovery plan for only £19.
Are you in a lot of pain and want to get better as soon as possible? If so then why not book in for a new patient consultation, with treatment on the day, for £72.
References –
1 – Goodman C, Snyder K, (2007). Differential Diagnosis for Physical Therapists. Saunders, Philadelphia.
2 – De C, Williams AC, Davies HT, Chadury Y. (2000). Simple pain rating scales hide complex idiosyncratic meanings. Pain;85:457–63
3 – Hush JM, Refshauge KM, Sullivan G, De Souza L, McAuley JH. (2010) Do numerical rating scales and the Roland-Morris Disability Questionnaire capture changes that are meaningful to patients with persistent back pain? Clin Rehabil;24:648–57.
4 – Farrar JT, Young JP Jr, LaMoreaux L, Werth JL, Poole RM, (2001). Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. Pain;94:149–58.
5 – Lintonl, S.J., Nicholasl, M.K., MacDonaldl, S., Boersmal, K., Bergboml, S., Maherl, C. and Refshaugel, K. (2011), The role of depression and catastrophizing in musculoskeletal pain. European Journal of Pain, 15: 416-422.
6 – Lee M, Silverman SM, Hansen H, Patel VB, Manchikanti L (2011). A comprehensive review of opioid-induced hyperalgesia. Pain Physician, Mar-Apr;14(2):145-61.
7 – Boggero, I. A., Geiger, P. J., Segerstrom, S. C., & Carlson, C. R. (2015). Pain Intensity Moderates the Relationship Between Age and Pain Interference in Chronic Orofacial Pain Patients. Experimental aging research, 41(4), 463–474. doi:10.1080/0361073X.2015.1053770
8 – Edwards R, Fillingham R, (2001). Effects of age on temporal summation and habituation of thermal pain: clinical relevance in healthy older and younger adults. J Pain, Dec;2(6):307-17.
9 – E.J. Bartley, R.B. Fillingim, (2013) Sex differences in pain: a brief review of clinical and experimental findings. British Journal of Anaethesia Volume 111, Issue 1, Pages 52–58
10 – Craft RM. (2007). Modulation of pain by estrogens. Pain;132:S3–S12
11 – Huerta-Franco MR, Malacara JM. (1993). Association of physical and emotional symptoms with the menstrual cycle and life-style. J Reprod Med;38:448–54.
12 – Unruh AM, Ritchie J, Merskey H. (1999). Does gender affect appraisal of pain and pain coping strategies? Clin J Pain;15:31–40
13 – Wise EA, Price DD, Myers CD, Heft MW, Robinson ME. Gender role expectations of pain: relationship to experimental pain perception. Pain. 2002;96:335