Taking the Measure of Pain Assessment Tools: Which Have the Most Clinical Value? (A Q&A with Gillian Hawker, MD, MSc, FRCPC)

Gillian Hawker, MD, MSc, FRCPC

Gillian Hawker, MD, MSc, FRCPC, a practicing rheumatologist and clinical researcher, discusses the importance of standardized pain assessment in patients with arthritis, reviews clinically useful pain measures, and offers advice to clinicians on evaluating chronic arthritis pain. Dr. Hawker recently authored a chapter, “Measures of Adult Pain”, that was included in a special issue of Arthritis Care & Research, a journal of the American College of Rheumatology.

Why should physicians use standardized pain measures?

If you are treating pain, you should be evaluating and documenting both the quality and quantity of pain before and after treatment. Standardized pain assessment is helpful for both physicians and patients. People often find it difficult to remember how they felt a week ago, a month ago, or three months ago. Having a standardized and documented measure of their pain before treatment can help you evaluate treatment effect.

Which pain measures are clinically useful?

This depends on a number of factors, including, what question you are asking, your population group, and your available resources, including time. At minimum, ask patients about the severity, frequency, and exacerbating and relieving factors of their pain, as well as how the pain affects their activities, sleep, and mood. Physicians do not regularly use standardized measures and the reasons are usually time-related. Often, physicians think the measures are going to take much longer than they actually do.

The Pain Numeric Rating Scale seems to be the most commonly used in health care. How useful is this measure?

This measure uses an 11-point scale (from 0, no pain, to 10, worst possible pain) to ask a single question, such as, “On average over the past week (month, etc.), what has been the severity of your arthritis pain?” It is easy to administer, takes very little time, and can be completed independently by most patients. However, a single pain severity rating provides a simplistic view of the patients’ overall pain experience.

If pain is the primary reason for a patient’s visit, you should use one of the more comprehensive measures available. In a recently completed study, we found that people living with osteoarthritis do not like the 0-10 rating scale because it does not allow them to explain their pain experience fully.

Compared with primary care physicians, specialists are more likely to use measures that evaluate pain more thoroughly. For example, the Measure of Intermittent and Constant Osteoarthritis Pain (ICOAP) evaluates the overall impact of hip and knee pain due to osteoarthritis on things like mood, sleep, and quality of life. It also helps you to assess different kinds of pain in osteoarthritis, including constant pain and pain that comes and goes. If used in clinical practice, ICOAP should be interviewer administered; it takes less than 10 minutes to complete.

The McGill Pain Questionnaire (MPQ) was developed to evaluate different qualities of pain that are associated with many different conditions. This may be useful in sorting out the mechanism of the pain, and thus choosing the best treatment. The questionnaire is also interviewer administered and can take up to 20 minutes to complete.

How often should physicians assess pain?

Time intervals vary depending on whether you are looking at resolution of an acute event, resolution or treatment of chronic pain, or a combination of these. Depending on the situation, you may opt to assess pain weekly, monthly, or less often. In some cases, you may want the patient to document their pain daily or even multiple times per day in a pain diary.

How commonly are physicians using standardized pain assessment? While physicians do routinely ask about pain, more often than not they are not using a standardized measure. As a specialist who regularly receives referrals for assessment of patients with, for example, painful knee, I can say that having this detail about the pain would be very useful in triage.

References

Hawker, GA, Mian S, Kendzerska T, French M. Measures of Adult Pain. Arthritis Care and Research. 2011;63(S11):S240-S252.