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IASP 10 th WORLD CONGRESS Clinical and Legal SIG Satellite Symposium. Pain Assessment and Opiates in the Workplace. Cubberley Auditorium Stanford University School of Medicine 12-13 th August, 2002. Psychological Assessment. Difficulties in the assessment of chronic pain syndromes
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IASP 10th WORLD CONGRESSClinical and Legal SIGSatellite Symposium Pain Assessment and Opiates in the Workplace Cubberley Auditorium Stanford University School of Medicine 12-13th August, 2002
Psychological Assessment Difficulties in the assessment of chronic pain syndromes Chris J. Main Ph.D Tues 13th August 2002: 8.30 a.m – 9.00 a.m.
DEFINITION OF PAIN • Pain is defined as: • An unpleasant sensory and emotional experience associated with actual or potential damage, or described in terms of such damage........ • Pain is always subjective • IASP Committee on Taxonomy 1991
Puzzles about injury, pain and disability • There is only a weak relationship between physical injury (damage) and amount of pain • Pain does not always become chronic • Chronic pain does not always lead to significant disability • Therefore the relationship between injury and disability is not straightforward
Clarification of “biopsychosocial” • Biopsychosocial includes the physical basis (the “bio”), it is not an alternative • The “psych” includes emotions, beliefs and behaviour • The “social” includes cultural, family, economic and occupational • It is a framework for understanding the influences on disability in the INDIVIDUAL patient, employee or claimant
Possible influences of psychological factors • Prior to the accident • immediate • delayed onset • how much delay snaps the causal link? • Development across time • secondary reaction to persistence of pain • secondary reaction to disability
WHAT ABOUT “PRE-EXISTING” PSYCHOLOGICAL FACTORS • Long-standing personality characteristics • History of psychiatric illness • Key question: How do they affect: • The perception of pain? • Response to treatment • Development of chronic disability • Answer • Not a lot!
Psychiatric perspectives • Depression • Anxiety • generalised anxiety state • Phobic anxiety • Post-traumatic stress disorder (PTSD) • Somatisation • Based on historical pattern of symptom presentation • Heightened somatic concern
Limitations of the psychiatric perspective • In chronic pain, major mental illness seldom defined • Incidence of minor mental illness so high that diagnosis not helpful • Identification of “adjustment disorder” unhelpful • No requirement to consider beliefs, coping strategies or the development of chronic incapacity
Linton’s Review: Conclusions • Psychological variables important in the onset and development of neck and back pain problems • Emotional, cognitive and behavioural domains • Efforts should be made to incorporate the information better into clinical practice to enhance assessment and treatment Linton S.J. (2000) 25:1148-1156
Factors associated with chronicity and outcome: a framework • DISTRESS • symptom awareness and concern • depressive reactions; helplessness • BELIEFS about PAIN and DISABILITY • significance; controllability • Fears and misunderstanding about pain • BEHAVIOURAL FACTORS • guarded movements and avoidance patterns • Coping styles and strategies
A reflection on chronic incapacity • Most people following minor injury, strain or sprain recover (despite the fact that some get too much treatment!) • The development of disability needs to be understood as a process in which a number of factors , individually and in combination can become obstacles to recovery • Psychological factors appear to be particularly important
Chronic Acute Invalidism Sick leave Avoidance Depression ThePainLadder (Waddell, 1992, Weiser, 1997-1999) Main,2000 Helplessness Failed treatment Anger &blame Catastrophising Uncertainty & fear
What are the important Social factors? • Cultural and sub-cultural • Social environment • family • health care system • Economic • benefits • Compensation and medico-legal • Occupational
Occupational stress Occupational factors • stress • and recovery from injury
Psychological Factors In Work Absence • Perceptions of Work • High / conflicting) demands • Low control • Time pressure • Long working hours
Clinical and legal issues • But pain is subjective • You cannot measure it directly (unlike e.g. temperature) • Medical assessment is required • Defendants have a right to challenge the evidence • They may challenge not only the nature of the injury; but also the self-report of the claimant
Common reasons for seeking Psychological Opinion in Personal Injury • Identification of Primary psychological disorder • “Inadequate” physical findings to explain persistence of pain • Type of response to Physical assessment • “Excessive” • “Inconsistent” • Level of disability/ work compromise not explicable on organic findings • Doubt regarding legitimacy of symptoms • I.e. issues of credibility
PSYCHOLOGICAL EVALUATION Purpose of evaluation • Detection of specific psychological injury • diagnosable psychiatric disorder (e.g. DSM-IV) • Determination of a Psychologically-mediated pain syndrome • Evaluation of the genuineness or veracity of the client
WHAT ARE CHRONIC PAIN SYNDROMES ? • Clinical disorders in which pain has persisted despite treatment • Characterised by pain-associated dysfunction • May be • Neurogenic (nerve injury) • Disease related (e.g. cancer) • Psychologically mediated
PSYCHOLOGICALLY MEDIATED CHRONIC PAIN SYNDROMES 1 • Primarily a type of Pain disorder, rather than a psychiatric disorder • Psychological factors influencing the perception of pain or pain-associated disability • Psychological factors include • Thoughts and beliefs about pain and treatment • Emotional responses • Behavioural responses to pain
PSYCHOLOGICALLY MEDIATED CHRONIC PAIN SYNDROMES 2 • May present with highly specific pain-associated limitations • Or may be characterised by florid and widespread dysfunction • May include significant iatrogenic confusion and distress • Syndrome may be enhanced by the medico-legal process
PSYCHOLOGICALLY MEDIATED CHRONIC PAIN SYNDROMES 3 • May also have diagnosable psychiatric illness • A careful analysis is needed of their development across time • There are multiple influences on adjustment to pain • They often cannot be explained simply by the characteristics of injury or the immediate response to it
CONTENT OF A PSYCHOLOGICAL EVALUATION • Patient’s self report • Presenting symptoms • Clinical history and response to treatment • Behavioural observation • Psychometric tests • Interview with spouses/relevant others • Videotaped Evidence
FEATURES INFLUENCING PSYCHOLOGICAL EVALUATION • Comprehension • Neuropsychological impairment • I.Q. • Language & literacy • Concentration and fatigue • Distress : (symptoms, incapacities and litigation) • P.T.S.D.
ARRIVING AT A PSYCHOLOGICAL OPINION A complex task involving the integration of a number of different clinical dimensions. The major focus may rest less on the origin of pain….but more on the nature of the injury and the components of the resulting incapacity…. Each component of the psychological opinion should if possible be clearly appraised before an attempt is made to integrate the opinion.
Veracity of the Claimant • Who decides if the claimant is genuine? • Medical assessment of injury (and its sequelae) is required • Defendants have a right to challenge the evidence • They may challenge not only the nature of the injury; but also the self-report of the claimant
What about Malingering? • True malingering is probably relatively rare • It is a legal not a clinical “diagnosis” • The clinical equivalent is “total fabrication” • Probably rare • Those may be “filtered out” prior to joint instruction • Medico-legal issue is one of exaggeration • However the legal and clinical uses of the term are slightly different
What about Exaggeration? • Legally the term doesn’t imply intent as such; but some sort of mismatch is implied • Attribution of mismatch however implies a set of fundamental equivalences • Accident and injury • Injury and damage “physical signs” • Signs and symptoms • Symptoms and limitations (disability) • Disability and work compromise
Difficulties in assessment of exaggeration? • Three problems in providing a simple answer • 1 There are wide variations in symptoms, disability in work compromise which cannot be accurately predicted from injury or supposed damage • 2 Disability and work compromise are multiply determined • 3 Psychosocial factors are far more important than physical factors in the development of chronic disability
What sort of evidence do we have from a medico-legal assessment? • Claimants symptomatic presentation • Interview • Type of symptoms • Manner in which symptoms are presented • Accuracy & consistency of recall • Response to clinical assessment • Physical signs • Behavioural signs • Clinical / occupational records • Other medico-legal reports
Lets assume some sort of mismatch or exaggeration • Is it deliberate? • Is it with intent to deceive? • If so, properly a judicial matter; as a medicolegal expert, you can only lay out your “evidence” • Is it with intent to convince? • More likely if iatrogenic distress/confusion
A further question • Is it “unconscious” • Is it mediated by distress • Is it based on misunderstandings about pain, hurt and harming? • It it part of a “learned behaviour pattern”?
Current state of play • Undoubtedly we need better models of injury • We now know that the mechanisms of injury are different from mechanisms of chronicity • We need to consider injury and pain from a biopsychosocial perspective • This is still a lot we do not know about the nature and content of symptom presentation
Where do we go from here?Some unanswered questions • We must be clearer about the boundaries of clinical expertise. • What about specific expertise in deception and malingering? • Is there any? • Is it robust enough for medico-legal use? • What about “objective measures” • Traditional psychometrics; polygraphy, simulation tests,FCA etc? • Is there any place for simulation tests?
Problems in the development of a “Gold standard” • There is only a legal judgement in an extremely small proportion of cases • Most cases are settled by lawyers • Only potentially expensive cases are fought • Clinicians do not usually get lawyers specific feedback on specific strengths of their reports or critical issues • There is a lot of poker played (and bluff)
Do we need a “Gold standard”?If so, what sort? • Psychometric? • Behavioural? • Psychophysiological? • Performance evaluations? • Surveillance?
A scientific “Gold standard”:the challenge • We do not as yet have tools of sufficient sensitivity and specificity for medicolegal use in claimants with chronic pain • In offering ourselves as clinical experts we must be careful not to find ourselves in the role of “thought police” or moral adjudicators • That is the role for the law acting on behalf of society
Implications for medicolegal assessment 1 • “Hired guns” fit better into the old type of legislation than the new one • The prime responsibility of the expert witness is to the Court.. • It was always so. • Need to distinguish assessment of pain from assessment of veracity
Implications for medicolegal assessment 2 • A view on inconsistency or exaggeration may be asked of an expert witness • It should be in the context of a clinical assessment • But we need to a stronger evidence-base • Malingering is a matter for the Court
Principal references for this material 1 Main C.J. (1998) “Medicolegal aspects of pain” in PSYCHOSOCIAL FACTORS IN PAIN Ed. Gatchel R.J. and Turk D.C.: Chap 9: p132-147 Guilford Press, New York and London. 2 Main C.J. and Spanswick C.C., (1995) “Functional overlay and illness behaviour in chronic pain: distress or malingering?. Conceptual difficulties in the assessment of personal injury claims. Journ. Of Psychosom. Res. 39:737-753.
Principal references for this material 3 Main C.J. and Waddell G. (1998) “Behavioural responses to examination (a re-appraisal of the “non-organic signs”)” Spine: 23:2367-2371 4 Main C.J. (2003) “The nature of chronic pain. A Clinical and Legal Challenge”. In MALLINGERING AND ILLNESS DECEPTION: Clinical and Theoretical Perspectives Ed. Halligan P., Bass C. and Oakley D. O.U.P.; Oxford. In Press