Low back pain: unfit? just not doing much? or something else

For as long as I’ve been working in pain management (and probably well before), I’ve heard patients being described as ‘deconditioned’. From what we know about the effects of staying in bed because of illness or injury, it makes sense to think that if a person does very little they will become unfit. Common sense really. And from this assumption an industry of gym programmes and fitness initiatives have been instituted as an integral part of back pain rehabilitation.

Now before my physiotherapy colleagues start to lynch me, I’m not saying that these programmes should be banished into outer darkness because ‘reactivation’ has been shown to be effective in the recovery from back pain – but maybe it’s effective for quite a different reason from the one usually given.

Verbunt, Smeets & Wittink, in this editorial from Pain conduct a review of the relationship between physical inactivity and deconditioning in people with non-specific chronic low back pain, and find scant evidence for the strength of this belief.  Ooops.

There are several theoretical models that integrate the hypothesis that deconditioning is part of, and complicates, the recovery of people with chronic low back pain. The most popular in recent years is the pain-related anxiety and avoidance model (Vlaeyen and colleagues), in which people misinterpret their pain as threatening or something to be avoided at all cost, consequently fear moving, stop doing normal activities of daily living, and become deconditioned.  The model has been incredibly helpful for initiating a graded exposure approach to feared movements, and for shifting the psychological focus from low mood and into anxiety about pain and consequent behaviours.  BUT, as this review points out, it’s unclear whether being inactive and deconditioned maintain the ongoing disability.  And there is little evidence that being fit protects against experiencing low back pain in the first place.

As I said before, I’m definitely not arguing against the use of exercise as a component of rehabilitation for chronic low back pain – but at the same time, it’s really important to make sure the rationale for this is based on reality, not a myth.

Back to the findings of this review.  Firstly, is there evidence that people with chronic low back pain are actually doing less than people without? Basically, no.  But the pattern of activity can be quite different – people with ongoing tend to be just as active overall in a day, but their activity has peaks and troughs, what can be called ‘boom and bust’, or ‘saw-tooth’ pattern of activity.   Studies also show that people’s disability level is associated with their perception of how little they did – and this didn’t relate to their actual activity level.  Now that’s interesting – feeling like activities are obstructed by pain seems more salient to disability than the actual amount of activity carried out.  Perception is reality.

Are people with chronic low back pain less fit?

Several parameters are explored in this paper – deconditioning should be linked to changes in body composition (fat vs muscle), bone strength, muscle control and cardiovascular changes.

  • Body fat percentages are higher in people with chronic low back pain – but bone strength is equivocal.

Muscle strength and endurance should be affected if a person is deconditioned: ‘adaptive remodelling in muscles’.   This should be reflected in atrophic changes to the muscle as well as changes to the type of fibre found in muscles.

  • While some studies seem to show changes in paraspinal muscles, generalised atrophy isn’t found.  Biopsy of muscle fibres show atrophy of type II fibres, and this appears to be related to the duration of the low back pain. But the authors in this paper point out that these changes could be atrophy due to aging rather than back pain, and there were no studies to show the ratio between type I and IIX fibres in people with or without low back pain.
  • Postural control studies haven’t controlled for the level of physical activities of daily living, so it’s unclear whether any differences found are due to overall low activity level (which could have existed prior to the onset of back pain), or whether any changes were as a result of doing less because of low back pain.
  • Cardio fitness – well, here’s a kettle of fish.  There are loads of confounds – the type of exercise protocol used, work status comparisons, diagnostic comparisons, age and gender matching – it’s just not pretty.  This paper points out that there is conflicting evidence regarding cardiovascular deconditioning, or whether those who are working despite chronic low back pain are ‘fitter’ than those who are not, although there does appear to be a gender difference – males who are working appear to have better aerobic fitness than either women who worked outside the home, or males who did not work outside the home.  Maybe returning to work prevents cardiovascular deconditioning – but it’s unclear whether the types of work between women and men (both work in the home, and outside of the home) were controlled for.  Almost all the studies have used a cross-sectional design, so it’s really difficult to know whether deconditioning occurs after onset of pain, or prior to the onset of pain.  Low aerobic fitness and low activity levels do not appear to be risk factors for developing chronic low back pain.
  • Metabolic factors – insulin insensitivity is associated with low activity levels like lots of bed rest.  Unfortunately there were not studies examining this in people with chronic low back pain, and the level of inactivity required to develop insulin insensitivity hasn’t been determined.

Now it really does get interesting for me here.  I’ve griped about the lack of validity (and reliability) of functional capacity evaluations.  They rely on people being prepared to ‘give it their best’ and for many reasons people with chronic pain may not do so.  It could their concerns about pain immediately, pain the next day, or the implications of ‘good’ performance on things like compensation.  On the other hand, a one-shot assessment isn’t able to predict performance over a day or a week – and some patients ‘over-do’, others ‘under-do’, and even the influence of the person doing the assessment can change how well the individual performs a functional test.

The authors in this paper plead for researchers to:

(1) objectively monitor general physical activity level and control for this in statistical analyses of physical fitness

(2) consider studying the factors that influence performance during performance testing in order to improve validity

(3) use longitudinal designs rather than cross-section designs to ensure correlation isn’t confused with causation – and outcome measures should monitor the impact of functional activity gains

(4) confounds known to influence physical performance usch as gender, age, recreational activities, job type, diagnosis, etc should be monitored so multiple regressions can be carried out with some confidence

The summary?

There is little research evidence that people with chronic low back pain are deconditioned either before they developed their problem, or after.  Despite this, it’s thought that being fit in a generally active way is good for overall health and especially as we age.  Engaging in more exericse does have an effect on recovery from low back pain (well, reducing the disability associated with low back pain), but we don’t know why.  Just don’t assume that because someone perceives they’re disabled, they are actually unfit.

Verbunt JA, Smeets RJ, & Wittink HM (2010). Cause or effect? Deconditioning and chronic low back pain. Pain PMID: 20153582

On coercion and ethics

NB: this post is opinionated.  It represents my own opinions and not those of my employer, my colleagues, my family or my dog.  It’s mine all mine.

If there is something that gets me really riled up, it’s bullying.  Maybe I had too much bullying when I was a kid, maybe I just believe in justice, but for whatever reason I get very grumpy when I see bullying.  Unfortunately this time, I think I’m being bullied – and not by a small-time bully either.

This is a very large organisation that refuses to pay an invoice for services provided because of a paragraph I wrote in the final report.  The paragraph is factual and directly related to the issues the patient raised during the pain management programme.  It just doesn’t suit some members of the organisation that have received it.

I’ll name no names, and I’m being deliberately coy about details, but I’m not a happy woman.

What did I say that was so dreadful?

I said that functional capacity evaluations can’t be used to predict daily function.

A couple of weeks ago I posted on this topic saying that the cumulative evidence over years has not changed: functional capacity evaluations, no matter how well they are carried out, do not have good predictive validity. I’m not going to say it again, once is enough!  In fact, a document that a colleague and I produced for a very large health purchaser in 1999 came to the same conclusion, and produced a set of guidelines for case managers to use when considering a referral for FCE.

Could it be that this report was written for the same corporation that wants me to withdraw my comment? My lips are sealed!

I wrote about this  for RTW Matters just recently.  The fact is, we don’t have any magic way to find out whether someone can or can’t return to a job except through doing it.

I understand that it’s incredibly difficult to determine whether someone deserves a benefit on the basis of whether they are incapacitated.  One author calls doctors who decide this ‘designated guessers’. The main reason health providers find it so difficult is that the decision is not a medical one.  It’s a socio-political one.  It’s based on  a ‘contract’ between members of a community.  It’s fraught with issues of honesty, intent, morality – and yes, in the case of ‘invisible illnesses’, it has the potential to be abused.

But is that something I need to think about when I write a report about things relevant to a client’s pain management programme?  It seems that I do, when the organisation paying for this report uses FCE as part of its process to decide whether someone has ‘capacity for work’.

Let’s put that aside for a moment and consider some of the ethical issues that I think are being challenged if I do what this organisation wants.

  1. Not accurately recording the issues relevant to the client’s programme
  2. Not disclosing the limitations of an assessment process
  3. Denying the client social justice by not providing him with information relevant to the assessment he has completed (I have to ask what the provider of the FCE was thinking about in terms of ethics: isn’t there a responsibility to advise people about the limitations of any assessment?)
  4. Asking me to collude with providing an inaccurate representation of the client’s concerns and content of the programme

There could be more..but that’s enough, don’t you think?

I guess the most worrying aspects of this whole affair are these:

  • this organisation isn’t saying I’m inaccurate in what I say about FCE – they just don’t like it, and think I shouldn’t say it.
  • they are using (and abusing) their position of power to coerce me into doing something that I think is unethical.
  • at the same time they’re trying very hard to deny a client the information he should have access to in order to defend against the opinion of the FCE provider.
  • AND the organisation is prepared to require this client attend another unnecessary programme just so they can get a report that suits their purpose.

What am I going to do?

If I was expressing an opinion, I might change or temper what I said.

If the client hadn’t raised this as a specific concern during the programme (and hadn’t identified ‘establishing functional abilities for work’ as a goal from the Plan of Action), I might have reconsidered a little.

But by not paying for the whole programme and report, and by suggesting the client might be required to go through another programme (unnecessarily) with another provider just to get a report this organisation likes, I’m Not Happy Indeed.

If I worked as a private practitioner in a solo practice, how would I respond to this kind of – well, let’s be honest, bullying?  Who would support me against a large organisation with a lot of purchasing power?  And who’s looking after the interests of the client?

At this stage the client doesn’t even know about the furore (and is probably wondering why the report hasn’t reached him yet – we’re not allowed to give him a copy of the report directly).

What do you think about it?  I’m keen to know your thoughts.

Functional capacity evaluations – my take on them!

Functional capacity evaluations

There are many forms of functional assessment available.  These range from a series of structured activities carried out in the home or work environment over a period of days or weeks to those that are carried out in a very precise manner in a clinic and often under the supervision of an occupational therapist or physiotherapist.  Both commercial (ie standardised and franchised) ‘Functional capacity evaluations’ (FCE) are available, as well as semi-structured or individualised assessments.

The term functional capacity evaluation has been criticised, because it can suggest that it is able to assess ‘capacity’ or ‘can do’, while most commentators believe that functional assessments can only assess what a person ‘will do’ (e.g. Battie & May, 2001).

One of the major criticisms of FCE is that few studies of reliability or validity have been published in peer reviewed journals.  This means most FCE have not been subject to the degree of scrutiny that is usually employed when developing assessment tools.  The relatively few studies that are available suggest that ‘only limited aspects of FCE reliability have been studied’ (Battie & May, 2001), and predictive validity, or the ability of the FCE to predict whether someone can or will return to work, is not strong (e.g. Gross, Battie & Cassidy, 2004)..

Reliability refers to whether two different people can conduct the FCE and obtain the same results (e.g. inter-rater reliability).  Intra- and interrater reliability for most FCE methodologies  have not been established.  There is some evidence that interrater reliability for establishing between ‘light’ and ‘heavy’ exertion, and whether a lift is performed safely, but mixed findings have been obtained for identifying the level that would ‘constitute safe, maximal lifting’ (Battie & May, 2001).  This means that when reviewing the findings of FCE, it is uncertain whether the same results would be achieved a second time, or by a different assessor.

Validity refers to whether an assessment is measuring the dimension it says it is measuring.  There are several different types of validity – content validity refers to whether the items used in the assessment ‘look like’ and agree with other ways of measuring a similar area – for example, do the items in the FCE measure the same sort of areas that disability questionnaires measure?  If they do, there should be a degree of similarity between the scores on both type of assessment if they’re completed by the same person.

Reneman et al. (2002) found little to moderate correlation between the self-report and performance-based measures, while Gouttebarge et al. (2009) found poor construct validity of lifting tests, discriminative validity was not statistically established, and convergent validity with self-reported pain intensity and disability was poor.

One of the most important aspects of validity is whether the results from an assessment can be used to predict behaviour in the ‘real world’ – this is predictive validity.  Gross and Battie (2005), found that FCE did not predict function at 12 months, and stated in a further paper that ‘The validity of Functional Capacity Evaluation’s purported ability to identify claimants who are “safe” to return to work is suspect.’ (Gross, Battie & Cassidy, 2004).  A very recent study demonstrated that while FCE was related to return to work the predictive efficiency is poor, with the findings contributing only 5% to the overall model (Striebelt, et al.2009).

Strong and colleagues provide recommendations as to how FCEs should be requested, undertaken, reported and particularly applied to reduce work disability among injured workers and this paper, in part, describes my approach with clients when discussing the relevance and limitations of FCE results (Strong et al. 2004).

FCE can provide some helpful information to both client and health provider when used as a ‘pre and post’ assessment, to monitor functional improvement, and to assist a client to develop an awareness of the areas of functional performance he or she may need to improve on (such as improving grip strength, manual handling technique or cardiovascular fitness).  At the same time, FCE is a measure of volitional behaviour at one time in a clinical setting, as opposed to a ‘real world’ setting where consistent performance is necessary.  As I have indicated above, the predictive validity of FCE is not strong, and FCE should not be relied upon to determine ability to carry out activities over the course of a day or week.

Gouttebarge, V., Wind, H., Kuijer, P. P., Sluiter, J. K., Frings-Dresen, M. H., Gouttebarge, V., et al. (2009). Construct validity of functional capacity evaluation lifting tests in construction workers on sick leave as a result of musculoskeletal disorders. Archives of Physical Medicine & Rehabilitation, 90(2), 302-308.

Gross, D. P., & Battie, M. C. (2006). Functional Capacity Evaluation Performance Does Not Predict Sustained Return to Work in Claimants With Chronic Back Pain. Journal of Occupational Rehabilitation, 15(3), 285-294.

Gross, D., Battie, M., & Cassidy, J. (2004). The prognostic value of functional capacity evaluation in patients with chronic low back pain: part 1: timely return to work. Spine, 29(8), 914-919.

Gross, D. P., Battie, M. C., Gross, D. P., & Battie, M. C. (2004). The prognostic value of functional capacity evaluation in patients with chronic low back pain: part 2: sustained recovery Spine, 29(8), 920-924.

Reneman, M. F., Jorritsma, W., Schellekens, J. M., & Goeken, L. N. (2002). Concurrent validity of questionnaire and performance-based disability measurements in patients with chronic nonspecific low back pain. Journal of Occupational Rehabilitation Vol 12(3) Sep 2002, 119-129.

Soer, R., Groothoff, J. W., Geertzen, J. H. B., Cp, Reesink, D. D., & Reneman, M. F. (2008). Pain response of healthy workers following a functional capacity evaluation and implications for clinical interpretation. Journal of Occupational Rehabilitation, 18(3), 290-298.

Streibelt, M., Blume, C., Thren, K., Reneman, M. F., & Mueller-Fahrnow, W. (2009). Value of functional capacity evaluation information in a clinical setting for predicting return to work. Archives of Physical Medicine & Rehabilitation, 90(3), 429-434.

Strong, S., Baptiste, S., Clarke, J., Cole, D., & Costa, M. (2004). Use of functional capacity evaluations in workplaces and the compensation system: A report on workers’ and report users’ perceptions. Work, 23(1), 67-77.

Functional capacity evaluations – do they predict function in the ‘real world’?

What do you do when a client has a goal ‘to establish functional abilities for work’, spends a lot of time looking at setting baselines at home, develops a good knowledge of how to maintain consistency, starts to work and sustains abilities in a specific workplace, then completes a functional capacity evaluation that says he can do more than what he’s identified he can?

I’ve had a long-standing interest in whether functional assessments carried out in a clinic or work setting over a single session (or even two-day period) can predict sustainable function in a ‘real world’ setting such as work. There are many different types of ‘work sampling’ methods that purport to measure functional ability, ranging from specialised machines and standardised set-ups like Valpar to Isernhagen to simple ‘lift and carry’ and walk, crouch or squat tests carried out by occupational and physiotherapists.

Most of these tests have some degree of reliability – that is, they can be carried out by two different people or over two different times and the result will be the same. What they do seem to lack is validity – specifically, predictive validity. What this means is that they don’t have a good track record of being able to predict from the results of the testing whether someone can actually return to work, or even a specific job.

There are quite a few reasons for this – most FCE’s sample what a person WILL do within a clinic setting over a relatively short period of time. Issues of tolerance or performance consistency over an eight hour day or 40 hour week are not sampled, neither are the tasks carried out in the same way or under the same conditions as in a real work setting (like having a deadline, need to make a profit, boredom, having an argument with a coworker – or even the same sort of container, starting position or lighting).

FCE’s can’t establish what a person CAN do (I don’t know of any way to establish this!), simply what the person will do on that day. So if the person is fearful of increasing pain (or worse – harming him/herself), or hasn’t carried out that specific activity for a long time, or even if the person is worried about what the assessment findings will mean in terms of the future – well, their performance may be a lot lower than what they would do in a completely different setting.

More than these factors, though, is that FCE’s don’t measure some of the most important factors that predict whether a person will return to work – I know of only one FCE that integrates psychosocial factors relevant to return to work within the testing format. Some testing batteries include questionnaires but don’t integrate the findings from these with the results of the assessment. Most place the majority of emphasis on biomechanical factors – can the person walk, bend, twist, reach, carry and lift?

In my client’s case, as a result of his FCE, he experienced a real increase of his pain. This is quite normal – even people without chronic pain experience an increase in their pain the day after they’ve completed a standard FCE (Soer, R; Groothoff, J; Geertzen, JHB; et al. 2008). He coped quite well with the increase, but for some people this is a real problem – especially those who haven’t developed effective flare-up management plans, or who catastrophise. On the other hand, he also recognised that he wouldn’t be able to sustain the level of performance he’d achieved during the test. This meant that, to him, the results were inaccurate, and he felt quite fearful that they would be misinterpreted by people who were unaware of the limitations of an FCE.

As a health professional, one job I take quite seriously is to help people recognise the limitations of various investigations and assessments. This is an ethical responsibility in terms of the assessments I conduct and on which I report. For example, if I was doing cognitive testing I’m ethically bound to advise the client that the results obtained on such a test would not be the same as what they would achieve in the ‘real world’.

I often discuss the limitations of MRI, CT and x-ray with people who have pain. Most of them have a strong belief in the value of these tests to ‘detect pain’ – it’s mistaken. There are many people with quite marked changes on radiological investigations that have no pain, while I can’t think of one instance where these investigations show pain. Similarly, I think it’s important to discuss the limitations of other testing procedures – one of them being functional capacity evaluations.

The results from FCE’s do have limitations, and for clients who are anxious about their ability, perhaps have spent much of their rehabilitation time learning how to reduce their level of activity so they can achieve consistent and reliable performance, it’s important to help them understand these limitations and trust what they have learned for themselves.

Unfortunately, this may not be what a case manager wants to hear. After all, they have a process to follow, and a degree of trust in the results. It must be unsettling to have one health professional critique the validity of an assessment carried out by another health professional. I can recognise the desire for case managers and others within a compensation environment to try to find some way to ‘objectively’ determine whether someone can or can’t do specific tasks.

But – and you knew there would be a ‘but’ – in this case, the ‘objectivity’ of a functional capacity evaluation doesn’t mean that it is providing a measurement that means anything with regard to return to work. Reliability is a great thing for an assessment to have, but a measure can be reliably measuring the wrong thing.

What can a functional capacity evaluation measure? It measures what a person will do in a clinical testing situation on a given day or days over a specific set of activities. It does not measure ‘can do’, it measures ‘will do’, and it doesn’t measure ‘can do at work’, it measures ‘will do here and now’.

For some interesting reading on FCE, take a look at the following readings:
Geisser ME. Robinson ME. Miller QL. Bade SM. (2003). Psychosocial factors and functional capacity evaluation among persons with chronic pain. Journal of Occupational Rehabilitation Dec;13(4):259-76

Gibson, Libby; Strong, Jenny; Wallace, Alison.(2005). Functional Capacity Evaluation as a Performance Measure: Evidence for a New Approach for Clients With Chronic Back Pain. Clinical Journal of Pain. Vol 21(3) May-Jun , 207-215.

Reneman, Michiel F; Jorritsma, Wim; Schellekens, Jan M. H; Goeken, Ludwig N. H.(2002). Concurrent validity of questionnaire and performance-based disability measurements in patients with chronic nonspecific low back pain. Journal of Occupational Rehabilitation. Vol 12(3) Sep, 119-129.

Soer, R., Groothoff, J., Geertzen, JHB., van der Schans, C P., Reesink, DD., Reneman, M F., (2008). Pain response of healthy workers following a functional capacity evaluation and implications for clinical interpretation. Journal of Occupational Rehabilitation. 18(3) Sep 2008, 290-298

Wallbom AS. Geisser ME. Haig AJ. Yamakawa K. Montgomery D. (2002). Concordance between rating of perceived exertion and function in persons with chronic, disabling back pain. Journal of Occupational Rehabilitation. 12(2):93-8

‘its taken over my life’…

Each time I spend listening to someone who is really finding it hard to cope with his or her pain, I hear the unspoken cry that pain has taken over everything. It can be heartbreaking to hear someone talk about their troubled sleep, poor concentration, difficult relationships, losing their job and ending up feeling out of control and at the mercy of the grim slave-driver we call chronic pain. The impact of pain can be all-pervasive, and it can be hard to work out what the key problems are.

To help break the areas down a little, I’ve been quite arbitrary really. I’m going to explore functional limitations in terms of the following:
1. Movement changes such as mobility (walking), manual handling, personal activities of daily living
2. Disability – participation in usual activities and roles such as grocery shopping, household management, parenting, relationships/intimacy/communication
3. Sleep – because it is such a common problem in pain
4. Work disability – mainly because this is such a complex area
5. Quality of life measures

The two following areas are ones I’ll discuss in a day or so – they’re associated with disability because they mediate the pain experience and disability…as I mentioned yesterday, they’re the ‘suffering’ component of the Loeser ‘rings’ model.
6. Affective impact – things like anxiety, fear, mood, anger that are influenced by thoughts and beliefs about pain and directly influence behaviour
7. Beliefs and attitudes– these mediate behaviour often through mood, but can directly influence behaviour also (especially treatment seeking)

There are so many other areas that could be included as well, but these are some that I think are important.
Before I discuss specific instruments, I want to spend yet more time looking at who and how – and the factors that may influence the usefulness of any assessment measure.

Who should assess these areas? Well, it’s not perhaps who ‘should’ but how can these areas be assessed in a clinical setting.

Most clinicians working in pain management (doctors, psychologists, occupational therapists, physiotherapists, nurses, social workers – have I missed anyone?) will want to know about these areas of disability but will interpret findings in slightly different ways, and perhaps assess by focusing on different aspects of these areas.

As I pointed out yesterday, there are many confounding factors when we start to look at pain assessment, and these need to be borne in mind throughout the assessment process.

How can the functional impact of pain be assessed?

  • Self report, eg interview, questionnaires – and the limitations of these approaches are reliability, validity threats as well as ‘motivation’ or expectancies
  • Observation, either in a ‘natural’ setting such as home or work, or a clinical setting
  • Functional testing, again either in a ‘natural’ setting such as home or work, or a clinical setting – and functional testing can include naturalistic procedures such as the AMPS assessment, formal and structured testing such as the 6 minute walk test, the sock test, or even certain functional capacity tests; or it may be clinical testing such as manual muscle testing or range of movement, or even Waddell’s signs

All self report measures, whether they’re verbal questions, interview or pen and paper measures are subject to the problem that they are simply the individual’s own perception of the degree of interference they attribute to pain. The accuracy of this perception can be called into question especially if the person hasn’t carried out a particular activity recently, but in the end, it is the person’s perception of their abilities.

All measures need to be evaluated in terms of their reliability and validity – how much can we depend on this measure to (1) assess current status (2) contribute to a useful diagnosis (or formulation) (3) provide a basis for treatment decisions (4) evaluate or measure function over time (Dworkin & Sherman, 2001).

Reliability refers to how consistently a measure performs over time, person, clinician.

Validity refers to how well a test actually measures what it says its measuring.  The best way to determine validity is if there is a ‘gold standard’ against which the test can be compared – of course in pain and functional performance, this is not easy, because there is no gold standard!  The closest we can come to is a comparison between, for example, a self report in a clinic on a pen and paper test compared with a naturalistic observation in a person’s home or workplace – when they’re not being observed.

Probably one of the best chapters discussing these aspects of pain assessment is Chapter 32, written by Dworkin & Sherman chapter in the 2nd Edition of the Handbook of Pain Assessment 2001 (DC Turk & R Melzack, Eds), The Guilford Press.

Importantly for clinicians working in New Zealand, or outside of North America and the UK, the reference group against which the client’s performance is being compared, needs to be somewhat similar to the population the client comes from.  Unfortunately, there are very few assessment instruments that have normative data derived from a New Zealand or Australasian population – and we simply don’t know whether the people seeking treatment in New Zealand are the same on many dimensions as those in North America.

I’m also interested in how well any instruments, whether pen and paper, observation or performance-based assessment translate into the everyday context of the person.  This is a critical aspect of pain assessment validity that hasn’t really been examined well.  For example, the predictive validity (which is what I’m talking about) of functional capacity tests such as Isernhagen, Blankenship or other systems have never been satisfactorily established, despite the extensive reliance on these tests by insurers.

Observation is almost always included in disability assessment. The main problems with observation are:
– there are relatively few formal observation assessments available for routine clinical use
– they do take time to carry out
– maintaining inter-rater reliability over time can be difficult (while people may initially maintain a high level of integrity with the original assessment process, it’s common to ‘drift’ over time, and ‘recalibration’ is rarely carried out)

While it’s tempting to think that observation, and even functional testing, is more ‘objective’ than self report, it’s also important to consider that these are tests of what a person will do rather than what a person can do (performance rather than capacity). As a result, these tests can’t be considered infallible or completely reliable indicators of actual performance in another setting or over a different time period.

Influences on observation or performance-based assessments include:
– the person’s beliefs about the purpose of the test
– the person’s beliefs about his or her pain (for example, the meaning of it such as hurt = harm, and whether they believe they can cope with fluctuations of intensity)
– the time of day, previous activities
– past experience of the testing process

And of course, all the usual validity and reliability issues.
More on this tomorrow, in the meantime you really can’t go far past the 2nd Edition of the Handbook of Pain Assessment 2001 (DC Turk & R Melzack, Eds), The Guilford Press.

Here’s a review of the book when the 2nd Edition was published. And it’s still relevant.

‘Faking’ or ‘Malingering’ or ‘Exaggerated Pain Behaviour’

Hot words!!

It’s amazing how often health providers get asked directly or indirectly whether someone experiencing pain is ‘faking’ it. The short answer is the most accurate – we can’t tell. We’re not lie detectors, there is no ‘gold standard’ to work out whether someone is pretending or not, and the question is based on erroneous thinking about pain and pain behaviour.

I can almost feel the spluttering at my last sentence from some readers!

Let’s look at this more closely.

Remember the biopsychosocial model of pain states that the experience of pain and pain behaviour is influenced by three broad groups of factors: the biomedical/biophysical factors such as extent of tissue disruption at the periphery (or site of trauma), neurological changes of transmission and transduction (throughout the peripheral and central nervous system), and disturbance of the neuromatrix.

At the same time, there are psychological factors such as the level of alertness and arousal, attention, past learning, expectations, beliefs, attitudes, mood, contingencies and so on.

And there is also a range of social factors such as the presence or absence of social support, the systems in which the event occurs (such as compensation, availability of health care and technology), cultural expectations, religious beliefs at the same time as the other two factors.

Recall that pain is not the same as pain behaviour – pain behaviour is everything that we do in response to pain, including involuntary physiological responses (flushing, sweating), reflexes (withdrawal), verbal utterances (groans, gasps, requests for help), as well as complex behaviours such as reaching for medication, going to see a doctor, asking for time off work etc.

Pain behaviour is subject to all the usual influences on any behaviour – that is, operant conditioning can be involved, as well as classical conditioning. And pain behaviour has developed from the behaviour we displayed as a baby to the more complex and modulated behaviours we demonstrate now.

So, it’s easy to see that pain behaviours vary hugely between individuals even if the original trauma is exactly the same.

I can understand several things about the question ‘can you tell if he’s faking’. Pain behaviour elicits strong emotions in observers – it’s designed to do just that! It communicates, and something we like to do as humans is work out whether someone is lying or not. The problem is – we’re not very good at telling who is and is not lying (but we like to fool ourselves that we personally don’t fall for liars!).

In a litigation or compensation situation, it would be great to work out exactly ‘how much’ each pain is worth in order to give it a dollar value, and determine compensation. But – pain can’t be measured directly, we have to use pain behaviour as the next best thing – and pain behaviours are influenced by a whole lot of things. So it’s not a very reliable measure.

Another reason for wanting to know ‘is he faking’ is how far to ‘push’ the person into doing more. The underlying concern is ‘will I cause harm’. And again we really don’t have any useful measure if we try to have pain or pain behaviour as our guide. We need to use something else – radiological union perhaps, control of a load, heart rate and respiration.

BUT the question is based on the assumption that there ‘should’ be a certain amount of pain behaviour for a certain amount (or length of time since) tissue damage. And there simply isn’t.

Some allied questions….‘can’t you use functional capacity testing to work out whether someone’s faking?’ No – sorry. A functional assessment, just like any physical examination or test, tells you what the person will do, and perhaps how consistently they will do it – today. Few, if any, FCE’s have demonstrated predictive validity – that is, they don’t accurately predict how much someone will or won’t do in a day-to-day ‘real’ situation, in fact they won’t tell you what the person can and cannot do at all.

What does this ‘consistency of effort’ tell me? Just that – how consistent this person carried out this activity this time. It doesn’t predict anything, and certainly doesn’t tell whether someone is ‘faking’. People vary in their consistency of performance depending on: their initial expectation of the activity (it may have been harder or easier than they first thought); their prediction of the effect of doing that activity (they may predict they will have an increase in pain – and therefore reduce effort, or perhaps increase effort in order to convince the examiner that they are trying hard); their fear/anxiety may vary throughout an activity; their past experiences may influence what they are prepared to do. Even when given the same instructions ‘use maximal effort’ – if a person hasn’t done anything very physical for a while, ‘maximal effort’ may be hard for them to predict. Some may even be ‘saving themselves’ for activities later in the assessment battery.

But surely some people do fake! Yes – but it’s not a health or medical matter. It’s just not helpful to work out whether someone is or isn’t faking. What happens if you do somehow detect ‘faking’? Confront the person? Take their health care away? Tell them to pull themselves together?

It’s more helpful to think about what factors might be initiating and then maintaining this behaviour – then start to work on these variables to promote change.

But I’ve seen even eminent researchers use the term ‘exaggerated illness behaviour’. Yes, well, even eminent researchers can be mistaken! All that we can observe is that this person behaves in this way at this time in this setting, and the person attributes the behaviour to pain (or illness). We can only identify all the possible factors that are contributing to the maintenance of the behaviour, elicit from the person the not so good things about the situation they find themselves in (and acknowledge the good things about their situation), and help increase the importance they place on making changes, and support their confidence to start to make changes. This might mean leveraging off contingencies (reducing compensation, withdrawing spouse support) if these things are maintaining the behaviour – but it may also mean simply resolving ambivalence about the positives of moving forward.

Malingering? Faking? Exaggerating? When someone can tell me why yellow is better than blue, or find a measure of the ‘chocolateness’ of chocolate and the banana-ness of a banana, perhaps we may have found an objective pain measure. Until then, don’t ask me to work out whether someone is faking it, just ask me to help them move forward.

Oh, and just for fun – how many different words are used to suggest that someone is ‘faking’?

– functional overlay

– supratentorial factors

– a ‘genuine’ man (as opposed to a fake one, or one that is faking)

– adopting the ‘sick role’ (if someone believes they are sick/unwell, what can we expect? How many people do we see ‘adopting the well role’?)

– demonstration of non-organic signs (now that one’s actually interesting, as Gordon Waddell states very clearly in his book ‘The Back Pain Revolution’ (2nd Ed), he never intended the term to mean anything other than to suggest the person was experiencing increased psychological distress – and NEVER to be used as a means of detecting faking!)

This paper by Michael Sullivan is a little philosophical, but at the same time illustrates the points I’ve tried to make above.
This reference is from the 2001 version of the New Zealand ‘Yellow Flags’ document on acute low back pain management.

It’s actually quite hard to come up with good (quality, evidence-based) references on ‘malingering’. By far the majority of articles I located using Google, searching on the terms ‘malingering pain behaviour’ suggested that somehow ‘medical people’ or ‘psychologists’ or ‘psychiatrists’ using special tests can identify malingerers. Someone please show me the ‘special test’!! This section of the IASP Core Curriculum should put to rest this sad aspect of the management of people experiencing persistent pain. Detection of malingering is best left up to private investigators, leaving health care providers to the really difficult work of helping people recognise that change is possible, desireable and important.