The assessment of pain using a biopsychosocial (or sociopsychobiomedical) framework takes into account the multiple factors (social, psychological, biological) that influence the pain experience. It completes a more complex understanding of the patient’s pain perspective as well as identifying other targets for management. Factors do not always neatly fit into one category; for example, depression may have physical and social aspects as well as being a psychological factor influencing pain. A comprehensive pain assessment includes a:
- general assessment and pain-specific history (which explores the pain type, severity, functional impact, context, and the patient’s meaning of pain, expectations and fears)
- physical examination (assessing for signs of tissue damage or disease that might indicate nociceptive and/or neuropathic and/or nociplastic mechanisms of pain)
- psychological assessment (the pain experience is affected by mood, stress, coping skills, fear avoidance, and catastrophising).
This will inform the selection of treatment options most likely to be effective. The assessment may need to be repeated reasonably frequently, particularly while establishing a diagnosis and appropriate pain management.
The following descriptions provide more detail on the pain assessment including links to useful assessment templates and questionnaires.
General assessment and pain history
The standard medical assessment is as important in pain as it is in any other medical or psychological condition. Particularly with pain, history taking will explore multiple aspects such as any injury, details about the pain experience and impact, and attempted treatments (Table 1). The purpose of the assessment is to establish a possible physical mechanism of pain (whether it is nociceptive, neuropathic, nociplastic or a combination of aetiologies) and if there are underlying conditions or psychosocial issues.
When appropriate, a pain screening questionnaire may assist in the understanding of the patient’s pain experience. These include the Brief pain inventory, McGill pain questionnaire, DN4 neuropathic pain questionnaire and the Örebro musculoskeletal pain screening questionnaire.
Social assessment identifies factors in the patient’s environment that influence the pain experience. These include family and other relationships, work, life events, housing, sleep, activity and nutrition. Pain may be influenced by culture (eg seen as a way to strengthen the body, purify the soul or deepen the spirit with the idea of ‘no pain no gain’).
Pain influences interactions with others, occupational performance and self-care. Pain can be socially isolating, which can contribute to the pain–depression cycle. The patient should be questioned about the impact of pain on function (social and physical) and overall quality of life (Table 2). Specific questions might include the following:173 • Social and recreational functioning
- How often do you participate in pleasurable activities, such as hobbies, going out to movies or concerts, socialising with friends, and travel?
- Over the past week, how often has pain interfered with these activities?
- Mood, affect, and anxiety (for more information, refer to 2.3.3 Psychological assessment) – Has pain interfered with your energy, mood, or personality?
- Has pain affected relationships with family members, significant others, friends or colleagues? • Occupation
- Has the pain required that you modify your work responsibilities and/or hours?
- When was the last time you worked, and (if applicable) why have you stopped working? • Sleep
- Does pain interfere with your sleep? How often over the past week?
- How often do you do some sort of exercise?
- Over the past week, how often has pain interfered with your ability to exercise?
To assess the true impact of pain on the patient’s life, it helps to have familiarity with the patient and/or obtain input from their family, friends and support systems.
Occasionally, pain is used to gain sympathy, protection, benefits or medico-legal compensation.
A physical examination, including a thorough musculoskeletal examination, is particularly important in most of the chronic pain conditions and a relevant neurological examination is particularly important for neuropathic pain. A physical examination might include:
- assessing for signs of tissue damage/injury or disease that might indicate nociceptive and/or neuropathic mechanisms of pain (eg tissue deformity and cardinal signs of inflammation, or signs of neural disease or damage)
- careful evaluation for sources of referred pain (including viscera)
- looking for evidence of hypervigilance or guarding with particular movements. Compensatory postures and movements are important to analyse, as they might be placing extra load on sensitive tissues and addressing these early can avoid development of secondary issues
- looking for evidence of allodynia, hypoalgesia and hyperalgesia.
At the end of the examination, the GP should aim to establish a provisional diagnosis for the pain and the biomedical mechanism involved, as well as analysis regarding the disability level of the patient.
Psychological assessment explores the patient’s mood state, beliefs, thinking styles, coping skills, behaviours and responses that may contribute to the experience of pain, obstacles to recovery and treatment outcome.174 Psychological factors that contribute to the experience and impact of pain can be amenable to change175 and thus influence outcomes for the individual.176 There are screening tools for many of these factors.
Experience of both acute and chronic pain is commonly accompanied and influenced by mood and anxiety disorders.174 For example, anxiety is one of the most significant predictive factors for the severity of postoperative pain177 and there is a consistent association between CPSP and depression.125
Relevant beliefs include understanding of diagnosis and prognosis, and expectations about treatment, including willingness to be an active participant. Many people have a fear of pain, which contributes to the development of avoidance responses and can ultimately lead to disability. Thinking styles that are overly negative, ruminative and helpless (eg catastrophic thinking) are associated with more severe acute pain as well as persistent pain.178
Measurement of pain and functional impact
There are several pain scoring systems. Verbal numerical rating scales are often preferred because they are simpler to administer and give consistent results.179
The PEG scale may be useful in the general practice setting, particularly when assessing chronic musculoskeletal pain.109 Scores (out of 30) give a reference point for the patient’s overall wellbeing and can be used to compare the same patient seen at different times or by different practitioners.109
As so many factors influence the experience (and communication) of pain, it is not surprising that pain scores do not provide information about which patients are likely to respond to opioids.180
NPS MedicineWise has a pain diary that patients can access and download from their website.
Opioids are often useful analgesics, but care needs to be taken when prescribing these drugs to limit the risks, including inappropriate use and diversion. Clinically, problematic opioid usage is more likely when used in:
- younger patients – substance use issues generally commence before 35 years of age
- patients without a definite patho-anatomic diagnosis
- patients with active substance use problems or who are in contact with patients with such problems
- patients with active psychiatric problems
- patients who use benzodiazepines – concomitant use of opioids substantially increases the risks of side effects, particularly cognitive impairment, sedation and respiratory depression.181
Comprehensive assessment addresses the risk of opioid misuse.182,183 While screening for opioid risk has been recommended, at this point evidence of effectiveness is lacking. Additionally, treatment agreements and urine testing are also recommended but have not been shown to reduce overall rates of opioid prescribing, misuse, or overdose.5,103
Patients with a history of SUD are at higher risk of harms. A check of state-based prescription monitoring systems is advocated. Those patients with a history of SUD should probably not be offered opioids in a general practice setting, but, rather, if pain control cannot be gained by other means, should be offered referral to specialist services.
A UDS may reveal evidence of substances of which the practitioner is not aware. Not all substances are routinely tested for (eg oxycodone testing needs to be specifically requested). If such drugs are found, whether illicit or legal, the patient should be referred for specialist assessment and management. Contacting your local pathology provider may be necessary.