Chapter 13. Psychosocial Assessment of Chronic Pain

Why does one patient develop chronic pain and face disability, while another—with seemingly the same injuries, extent of tissue damage, and quality of medical care—recovers and returns to normal activity following a brief convalescence? Arguably, there may be biologic variables between the two that are difficult to discern medically, but a comparison, in most cases, is likely to reveal that the greater portion of the variance consists of psychosocial differences. When pain physicians wonder why a patient fails to respond to procedures and medications that have proven efficacious for many others with the same medical presentation, it is frequently the pain psychologist who can offer the most reasonable and, more importantly, functional set of hypotheses.

Although nociceptive or purely physiologic factors may instigate pain, how it is expressed by the individual, over time, suggests that what might have begun as a simple picture can become considerably more complicated and intricate through the influence of psychological and social factors. Melzack and Wall’s gate control theory emphasizes that pain cannot be fully understood without an assessment of the motivational-affective, sensory-discriminative, and cognitive-evaluative processes of the individual. Adherents to the biopsychosocial, mind-body, and behavioral medicine approaches to pain all affirm that, whereas the origin of pain may not be psychological, how one responds to it is. Assessing this response expediently and accurately may redirect the focus of a patient’s treatment, highlighting the psychosocial dimension of the patient’s experience as essential to diagnosis and successful outcome. Chronic pain may not lead to adjustment difficulties, mental disorder, and disability, but when it does, psychosocial assessment may offer the only helpful perspective on why, as well as the best hope for recovery.

Social policy and, in some instances, medical practice have lagged behind science in operationalizing the comprehensive approach to pain management. Psychological services, for example, are a requirement for pain treatment centers seeking accreditation by the Commission on Accreditation of Rehabilitation Facilities (CARF)1; yet many health insurance carriers balk at the idea of reimbursing for psychological evaluation and treatment, and there are no uniformly endorsed standards in the private sector. In medical practice, physicians who do not see their patients in a multidisciplinary setting may not involve psychological evaluation in cases of chronic pain, until considerable frustration and the question of functional versus organic origin has arisen. Ironically, by that time, the interpretation of the patient’s pain has often passed from a medical to a wholly psychological one, and the wish not to affront or unduly alarm the patient is well past consideration.

When patients are asked to see a psychologist or to complete a battery of psychological tests and questionnaires, many indeed respond defensively and, sometimes, even hostilely. For many, referral to a psychologist is tantamount to confrontation with their worst fear: “My doctor doesn’t believe me.” How the physician approaches the patient, therefore, frequently becomes the first crucial step toward putting together a comprehensive picture of what the patient is experiencing. It may prove helpful to remind patients that their chronic pain is likely one of the biggest problems in their lives—if not indeed the biggest—and that it would be surprising if it did not affect their relationships and usual ways of coping. The principal goal of psychosocial assessment in chronic pain is not, as some patients fear, to determine whether or how much pain can be attributed to psychological sources but rather to identify the emotional, behavioral, and social factors that may be complicating the experience of pain—prolonging it beyond its organic usefulness, rendering it less tractable to treatment, and moving the patient toward physical and psychological disability. The development of a successful plan for treatment often depends on identifying these influences and strategizing how to address them expediently, sensitively, and thoroughly.

In this comprehensive approach to chronic pain, the question of disability becomes more complex than one of straightforward injury and tissue damage. How the patient responds to his or her pain raises questions about the contributions of temperament, personality, coping style, psychopathology, and the dominant beliefs or explanatory model through which he or she tries to make sense of his or her pain. If these dimensions of the patient’s experience are not carefully and thoughtfully evaluated, then the risk of missing a critical piece of information relevant to planning treatment is greatly increased. A misstep can set the patient back, physically and emotionally, at once contributing to the needlessly increased cost of care and the frustration of providers, families, employers, and health insurance carriers.

Although successful treatment is the designated end of psychosocial assessment, psychologists may be asked to evaluate a range of secondary issues, including estimated course of health care utilization, probability of returning to previous employment, and probability of re-injury.2 Depending on the setting, they may also be asked to screen patients for the appropriateness of medical and surgical interventions, to evaluate the risk of substance abuse or suicide, to assess the likelihood of compliance with medical recommendations, and to render an opinion in the determination of whether a patient is partially or totally, temporarily or permanently disabled.3,4 Especially when the question of disability is raised, psychological evaluation may move to the foreground—not only as an assessment of those psychosocial factors contributing to disability, but as a vehicle for cross-validating the available medical findings.

Unfortunately, whether from the medical or the psychological perspective, there are few objective clinical or empirical measures with any reliability or predictive validity where the determination of disability based on chronic pain is concerned. Clinical data from physical examinations are often notoriously at variance with patients’ reports of their distress; and, to date, there are no laboratory measures available to quantify the experience of pain or even establish whether pain is present. What physicians have at their disposal in cases of chronic pain is frequently little better than their patients’ self-report and their own informed observation, whereas what they are usually asked to provide are “objective” findings. The use of clinical “signs” to establish the presence of nonorganic factors in pain is a well-established tradition,5 but such examinations are frequently skewed by patients’ attempts to draw attention to their plight by endorsing a broad range of sometimes contradictory symptoms.

When insurance carriers and disability determination boards ask for objective indications of disability, there is enormous potential for equivocating on the term objective, because many clinically important findings from physical examination are “semi-objective,” at best.6 The result is a growing dissatisfaction with health care for chronic pain by all concerned and a renewed emphasis on the need for a comprehensive approach to the problem.7 With so much at stake for the patient with chronic pain, a disservice is done, when diagnosis and treatment are undertaken haphazardly, fragmentarily, or even sequentially, by providers working independently without adequate cross-consultation. A comprehensive evaluation, involving a team of providers—pain physicians, pain psychologists, physical therapists, nurses, and complementary specialists—working toward an interdisciplinary synthesis of all the available data, may be the only means of ensuring the likelihood of an accurate, useful, and fair assessment of chronic pain.

Frustration in arriving at a reliable and predictively valid means of medically determining disability based on chronic pain, as well as numerous cases of failure prominently displayed in the media, has historically led to speculation that the causes of chronic pain may be primarily or wholly psychogenic and that only particular types of personality are affected. The search for the so-called pain-prone personality, however, never produced a satisfying or useful model and never received much empirical support.8,9 Given the array of variables, it would be surprising if a unified theory were to emerge. The combination of temperament, traits, coping style, influential beliefs, and a host of environmental factors is expressed uniquely in the personality of each patient. Furthermore, there is evidence suggesting that chronic pain unfolds according to a developmental course, in which each of the preceding variables may present differently, according to the level of psychological distress.8

If profiling offers few answers, there is nevertheless a valuable model proposed by the current heuristic approach to pain, which suggests that a range of factors may be associated with the subjective experience of pain, each of which can exert an influence on the individual’s unique interpretation of nociception. As chronic pain emerges over time, the interaction of psychological, social, and environmental factors with physical pathology tends to influence the patient’s perception of pain, as well as his or her interpretation of its impact on life, sometimes leading to disability and the adoption of the sick role.10 These psychosocial factors have been found to be even more influential than medical factors in the development and report of disability across cultures.11

Comparatively recent efforts to delineate those psychosocial influences with the greatest and most consistent impact on the development of disability have led to the identification of a number of largely independent risk factors associated with poor recovery from injury and the development of chronic pain. When these risk factors are present premorbidly or develop comorbidly with injury, they may complicate the patient’s subjective experience of pain, moving him or her toward a state of learned helplessness out of which chronic pain and disability can develop. One exhaustive review of the literature proposes a list of eight risk factors, documented as obstacles to the recovery from acute pain and as predisposing influences in the development of chronic pain.12 To these eight factors, the author has added one, (j), which has received much recent scientific scrutiny, and divided another into two (b and c). The resulting list of ten psychosocial factors can be further divided into comorbid and premorbid influences.

The only factor that may be considered exclusively comorbid is (a) pain duration. As pain endures, the likelihood increases that a chronic pain syndrome and disability have developed. Pain of 2 years’ duration is often cited as the decisive threshold, when multiple courses of medical or surgical intervention have failed to produce relief. When the criterion shifts to that of a successful return to work, however, much shorter durations of pain become actuarially significant. The likelihood of a patient’s returning to his or her old job, after 6 months of unemployment resulting from chronic pain, is only 50%; and, after a year, there is only a 10% chance of a successful return.

Two risk factors that may exert either a premorbid or comorbid influence are (b) a history of major psychopathology and (c) a history of substance abuse or dependence. Both of these factors may predispose an individual toward the development of chronic pain, but either may emerge from within the context of chronic pain, as well (see Chap. 14). The presence of premorbid mood, anxiety, psychotic, or personality disorder places an additional burden on the patient and may mean that he or she faces a new problem, such as injury and pain, with already compromised or maladaptive coping skills. Mood, anxiety, and adjustment disorders can also develop comorbidly, as expressions of the pain-stress cycle, contributing a new and, where the patient is concerned, often unprecedented burden. Somatoform disorders may have existed previously, with the focus on pain or other physical symptoms, or they may coalesce around the advent of a new constellation of symptoms. Premorbid problems with substance abuse can similarly predispose patients toward maladaptive coping strategies, leading to over-reliance on medications and noncompliance with medical recommendations. Substance abuse problems may also develop comorbidly in treatment, through the impulsive or injudicious use of opioid and anxiolytic medications.

The remaining psychosocial risk factors are generally considered to exert a premorbid influence on the development of chronic pain and disability. When patients report (d) job dissatisfaction, one of the principal motivations for recovery may be absent. When there is (e) a history of prolonged recovery from previous experiences of pain, the expectation that any injury or illness may require extended convalescence is already established. When there is (f) a pattern of reduced activity, coupled with excessive pain behaviors, supported by family and other social contacts who are either too solicitous or inconsistent or too harsh and punitive in their responses, the resulting struggles around secondary gain may completely derail treatment, giving disability a firm foothold. As factors predisposing patients toward the development of chronic pain, all three may severely inhibit the frequently necessary transition of the patient from passive recipient of care to active participant in care.

In cases where there is (g) a history of psychological or physical trauma or (h) a history of emotional, physical, or sexual abuse, chronic pain may represent a means of psychologically symbolizing and organizing an unbearable, traumatic event or series of events. When a patient’s focus on chronic pain and disability serves to defend against the experience of overwhelming affects by displacing emotional conflict onto the somatic sphere, the motivation to recover may be inhibited or removed. The high correlation between a history of childhood physical and sexual abuse, for example, and the development of chronic pain syndromes later in life is a well-documented phenomenon.13–15

The presence of (i) negative or anxiety-provoking beliefs about the meaning of pain suggests that—whether through misinformation, superstition, or distortion—the patient has acquired a set of maladaptive but nevertheless predisposing beliefs about his or her pain that are neither physiologically accurate nor psychologically realistic. One of the more persistent and insidious of these negative beliefs about chronic pain is that hurt means harm: “If it hurts, I must be injuring myself.” Other negative beliefs tend to lead to the premature conclusion of disability: “I’ll never be able to work again, if I can’t get rid of this pain!” This risk factor may not be prominent, until the advent of serious injury and pain; but it tends to reflect long-standing patterns of maladaptive coping and pessimistic thinking.

One last predisposing factor has been the focus of increasing attention in the past few years; namely, the patient’s (j) explanatory model of pain and how he or she interprets the meaning of pain in the context of his or her relationship to the world or to God.16 There is a growing body of surprisingly rigorous empirical studies suggesting that an affirmative outlook and an essentially optimistic philosophy can make a positive contribution to recovery from illness and the restoration of health. By contrast, patients who feel that their suffering represents a punishment or that they are being persecuted or victimized by pain often have an arduous path to recovery and may contribute to the poor tractability of their pain by assuming a passive, helpless role.

Although the presence of any of these ten risk factors (a–j) in a patient’s life predisposes toward the onset of chronic pain and disability, five psychosocial factors have been identified as predictors of negative outcome in the treatment of chronic pain.12 These include three of the factors already discussed—job dissatisfaction, reduced activity, and negative beliefs—coupled with a sustained attitude of hostility, anger, and alienation and a reliance on maladaptive coping strategies. Anger and hostility are disruptive of treatment and destructive of the alliance between physician and patient, often perpetuating the pain-stress cycle and thwarting intervention,17 whereas the maintenance of defective strategies for coping tends to disclose an inflexibility of psychological defenses. In both cases, psychotherapeutic intervention and management may prove necessary adjuncts to recovery. When one or more of these five factors is present, the course of treatment will almost certainly involve frustration for both patient and providers.

The influence of any psychosocial risk factor may signal reluctance on the part of the patient to give up his or her pain and suffering and relinquish the refuge of disability. Whether the motivation for this reluctance is unconscious conflict, primary or secondary gain, inflexibility associated with a personality disorder, psychopathology, deficits in education, or simply poor coping skills, investigators have found that patients vary considerably regarding how prepared they are to make changes in their behavior around the management of pain. The prevailing paradigm for understanding change in this context is the transtheoretical model, which proposes a series of stages that must be progressively negotiated, if change in behavior is to occur and endure.18,19 Although initially developed in the context of addictive behaviors and habit management, the model has been applied successfully to chronic pain in several settings and even across national boundaries.20–22

Assessing readiness for change may prove essential to understanding why some patients never seem to improve, as well as to the planning of interventions to promote behavioral change, active participation in care, and increased self-management of chronic pain. One way of assisting patients toward a greater acceptance of responsibility in the management of their pain is to help them see that changing or not changing is up to them and that they can choose to change. Cognitive therapy often begins with two questions that establish the cognitive framework within which change is possible: (1) What do you want (to change)? (2) What are you willing to do to get it?23 The first question is easy for most patients with chronic pain, but the second implies work and sacrifice and is not so easy when patients are preoccupied with their own suffering and deprivation. Assessing how ready patients are to do the work and make the sacrifice in their own behalf is a first and necessary step in deciding which interventions, both medical and psychological, are most likely to succeed and which are likely to fail or even cause harm.

The first stage in the transtheoretical model is precontemplation. It represents the point at which patients are highly resistant to change and disinterested in making any accommodation or adjustment in their own behavior, even for the sake of treatment. Such patients usually arrive at pain clinics with the attitude that only medical interventions will make any positive impact and that there is little they can do on their own to influence their pain. Patients in this stage are often characterized as helpless, passive, and highly distressed, and they typically challenge any suggestion that psychological factors can have any bearing on their pain.

Patients who are willing to consider the possibility that stress may affect their pain and that there may be steps they can take toward managing their stress and pain, even though they are not yet sure or committed, are in the contemplation stage. Such patients have begun to entertain and nurture the idea of change but are not sure how or whether they can do it. They have acknowledged that they are stuck, but they have no firm ideas about how to move forward. Much of the effort of psychoeducation in pain management programs is directed toward nurturing the appeal of change by challenging patients’ resistances and offering reasonable alternative explanations for what they are experiencing–in effect, moving them from the precontemplation to the contemplation stage of readiness for change.

Patients in the third or preparation stage have progressed to the point where they understand that change will offer them a route to more successful pain management, but they are not yet sure of what to change or how to begin changing. This stage often represents the time during which patients are considering their options and developing plans to make changes—whether adding new wellness behaviors, such as relaxation exercises, or dropping maladaptive behaviors, such as isolating themselves. The fourth or action stage represents the point at which the decision to change is translated into action. Patients endeavor to inhibit, reduce, or extinguish behaviors that cast them in the “sick” role and to promote and increase behaviors that give them a measure of control in managing their stress and pain. The fifth or maintenance stage sees them working to sustain the changes they have made, even through exacerbations and relapses. The motivation has shifted to the rewards of mastery and self-efficacy and the understanding that, not only is change possible, but it is desirable and even necessary, if pain is to continue to be successfully managed.

Because psychotherapeutic management in chronic pain encourages change in both behavior and attitude, it becomes critical to assess accurately where patients are in their readiness to make these changes. Recommending a course in relaxation techniques to a patient in the precontemplation stage will likely prove a futile and thankless intervention. Psychotherapy and, indeed, the efforts of all the members of a multidisciplinary team must respect and work within the context of the patient’s current stage of readiness if frustration is to be minimized and progress achieved. Clues regarding readiness for change can be gathered through the clinical interview of the patient, as well as by reviewing the medical record and interviewing the family; but a psychometric instrument has recently been developed with an already promising body of research behind it.

The Pain Stages of Change Questionnaire (PSOCQ) is a comparatively new entry in the panoply of measures devoted to the assessment of chronic pain.21 The PSOCQ applies the transtheoretical model of behavioral change, linked to a cognitive-behavioral perspective on chronic pain, in a 30-item, self-report format characterizing the patient’s stage of readiness on a continuum of four scales: Precontemplation, Contemplation, Action, and Maintenance. More research is needed to confirm the instrument’s predictive validity; however, the value of a measure that provides a means of cross-validating a patient’s simple profession of willingness to adopt a self-management approach to chronic pain may prove to be of enormous value in the selection of patients for particular approaches to treatment.

Evaluating which psychosocial risk factors may be influential in the life of a patient, as well as how committed that patient is to being an active, cooperative participant in his or her own care, are the objectives of psychosocial assessment in a multidisciplinary setting. The pain physician, like the psychologist, structures his or her time in discussion and examination of the patient, not only in the service of diagnosing pathology, but in an attempt to learn more about the patient’s experience and his or her responses to pain and illness. When one or more of the previously discussed psychosocial risk factors is identified as influential in the patient’s life, a referral for a more psychosocially based evaluation is indicated. In pain management centers and clinic or hospital-based practices, the psychosocial assessment of patients is usually coordinated by a psychologist, psychiatrist, clinical social worker, or psychiatric nurse practitioner.

The evaluation of the patient by the pain psychologist begins with a careful review of the available records in preparation for the clinical interview. When time and resources allow, the process may be extended to include (1) consultation with other providers, including the primary care physician; (2) ancillary interviews with family members; and (3) psychometric assessment. What happens during the time of the clinical interview is critical, not only because of the importance of the observations and data gathered by the psychologist, but because of the impression developed by the patient concerning the purpose and meaning of the visit. It is, therefore, essential to structure the time well and to make the patient feel comfortable and safe by allaying any fears and addressing any distortions he or she may harbor regarding how the information will be used. To overcome any initial defensiveness on the patient’s part, it is frequently helpful to begin by stating that the purpose of the interview is to find out more about the impact of the patient’s pain on his or her circumstances and level of functioning—how pain has affected his or her work, livelihood, family, relationships with friends, and personal goals.

Structured and Semistructured Pain Interviews

There are few structured interviews developed specifically for use with the pain patient, but one of the more widely used of these is the Psychosocial Pain Inventory (PSPI).24 This instrument guides the psychologist in gathering information from the patient and a family member through a series of 25 open-ended questions, all reflecting a psychosocial dimension of the patient’s experience of pain. The items included in the inventory explore major stressful life events, pain-related stressors, pain behavior at home, previous painful or disabling medical problems, and models of chronic pain in the patient’s family. An additional feature is that each of the 25 items can be scored according to a standardized system, with the goal of identifying those factors that are most influential in the patient’s pain. A drawback of the PSPI is that a careful administration often stretches into 1½ to 2 hours, sometimes taxing the patient and introducing a cost-effectiveness variable into practice management.

Semistructured interviews enjoy a wider use and broader application than structured interviews, but there is little standardization of format or administration among them. Many clinicians choose to adapt them still further to the needs of their settings. One attempt to describe the field of inquiry of the semistructured interview, regardless of format, suggests the necessary inclusion of seven objectives: (1) recording a careful pain history, (2) identifying the events that precede and follow exacerbations in pain perception and pain behavior, (3) evaluating daily activities and limitations, (4) determining whether there are family models of chronic pain and disability, (5) determining whether the patient has suffered physical or sexual abuse, (6) evaluating the degree of affective disturbance, and (7) determining the degree to which the patient is experiencing sexual dysfunction.25 Using these objectives as a guide, a useful semistructured interview can be developed for almost any setting or population of patients.

Psychiatric Interviews

Although not developed specifically for use with pain patients, structured and semistructured psychiatric interviews are administered routinely in many pain management centers, as well as in chronic pain research. The format of the psychiatric interview is designed to assess psychosocial history in depth and to juxtapose this “life story” with a patient’s current symptomatologic profile. The interview itself may be thought of as a tool for systematically disclosing the dynamic relationship between the two—history and symptoms. Two widely used, structured formats for the psychiatric interview are based on the current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). The National Institute of Mental Health Diagnostic Interview Schedule for DSM-IV (DIS-IV)26 and the Structured Clinical Interview for DSM-IV (SCID)27 were developed to assess not only current psychiatric symptoms and disorders but lifetime histories of psychiatric diagnoses, as well. Both instruments require a brief course of training, and either may be administered by nonclinician assistants; but the SCID offers greater latitude to supplement the structured interview with spontaneous questions for clarification and challenges to inconsistent responses. The DIS-IV also is offered in a computerized version, which can be interviewer-administered or self-administered.

Despite the advantages of a standardized and structured format, many pain psychologists prefer the greater latitude offered by the generic psychiatric interview adapted to the situation of chronic pain. Although there are essential elements to the psychiatric interview, there is no standard or established structure. Its strength, when administered by a skilled clinician, lies in its flexibility and interactive freedom. It is frequently organized along progressive sections, which minimally include (1) presenting problem, (2) history of presenting problem, (3) psychiatric history, (4) substance abuse history, (5) medical history, (6) developmental and social history, and (7) the mental status examination. Each of these broad components can be modified to pose questions relevant to the patient’s experience of pain; or, the entire format can be shifted to make chronic pain the presenting problem and focus of the interview.28,29

Table 13-1 presents an example of how the format of the general psychiatric interview can be altered to shift the focus to a psychosocially based clinical interview for chronic pain. All of the previously discussed, essential objectives of the semistructured pain interview can easily be incorporated into this format; and its inherent flexibility facilitates the investigation of the broad range of psychosocial issues and risk factors that may be associated with the patient’s particular situation of chronic pain.25 When the results of psychological testing are available, it is often revealing to discuss them, in brief, with the patient; and when the data gathered during the interview are at variance with his or her responses on the psychometric measures, it is usually a good idea to call attention to the discrepancy and to wonder aloud with the patient what it might mean—that is, to discuss it without drawing or presenting conclusions. Many patients may deny feeling depressed during the interview, for example, but may nevertheless endorse a number of items reflecting mood disturbance and neurovegetative difficulties on the Beck Depression Inventory (BDI) or Minnesota Multiphasic Personality Inventory (MMPI-2).

In the psychosocially based clinical pain interview, the pain psychologist has the opportunity to develop lines of inquiry sequentially or organically, in a purposeful manner, fashioning each successive question to the immediate verbal and affective responses of the patient. This is especially important when reviewing the patient’s questions and goals for treatment at the conclusion of the session. It is here that the patient’s beliefs about pain and explanatory model of pain can be discussed in comparatively greater depth. It is here, as well, that the first indications of his or her readiness for change may be revealed. The pain psychologist’s questions should be formulated to elicit additional information and elaboration, not to convey judgment or sabotage future plans for psychoeducation by attempting prematurely to correct distortions or offer more logical explanations. At this first encounter, understanding the patient’s experience should be the guiding principle.

The interview is an indispensable feature of psychosocial assessment; however, developing diagnostic and prognostic impressions and a treatment plan based solely on the patient’s verbal self-report can prove a problematic enterprise. Even in casual conversation, people are likely to forget, editorialize, distort, and defensively censor themselves—both consciously and unconsciously—when disclosing personal information; and the situation of the clinical interview, as a sample of human behavior, is no different. One study even suggests that patients with chronic pain who wish to appear socially conventional—the response bias of social desirability—typically report less depression and anxiety but higher levels of pain.30 Although it is not feasible to test the veracity of every statement, it is nevertheless possible to improve on the likelihood of arriving at an accurate appreciation of an individual patient’s experience and story. Comparing data gathered by other providers, reviewing the available records, interviewing family members, and administering one or more psychometric instruments are all ways of cross-validating the data from the clinical interview of the patient.

The point is not to catch patients in the act of consciously or unconsciously misleading their providers but to gain as accurate an assessment as possible of the impact of pain on their lives. When a patient denies having used opioid medications while a previous medical report refers to “drug-seeking behavior”; when a family member contradicts what a patient has said; when a testing report characterizes a patient as severely depressed and anxious, even though he or she insists otherwise—these are all inconsistencies that require elucidation, if the patient’s situation is to be understood. The addition of psychometric instruments elicits one more sampling of the patient’s behavior; and patients frequently react differently to the situation of completing a questionnaire or computerized test or inventory than they do to the direct questions of psychologists and physicians. Furthermore, because the methods of test construction sometimes obscure the intention of certain questions, the point or interpretation of any particular item or trend is not always immediately discernible, sometimes resulting in a less defensive response. Especially when preparing forensic reports or documentation for outside agencies, having an actuarial or statistically meaningful basis for cross-validating a patient’s verbal self-report makes psychometric measures an important addition to psychosocial assessment.

Measures Developed for Use in Chronic Pain

Of the literally thousands of psychometric measures available for use in clinical settings and research, hundreds have been created or adapted specifically for application to patients with chronic pain or chronic illness. Most of these are pencil-and-paper, self-report instruments, but some are available in software editions; and the computerized pain testing battery is becoming increasingly popular in pain management centers. A few of these measures are multidimensional in scope; however, most were designed to assess one dimension of the experience of pain, with the categories of assessment being generally defined as (1) pain intensity, (2) pain beliefs and coping, and (3) functional capacity.

Measures of Pain Intensity

Measures of pain intensity provide quantitative estimates of a patient’s pain. The simplest of these are unidimensional scales—numerical rating scales (NRSs) and visual analog scales (VASs)—which ask patients to depict the severity of their pain as a number on a scale of “0 to 10” or “0 to 100” or to represent it on a line or continuum with bipolar attributes, such as “no pain” to “worst pain.” These are often used as clinical or bedside measures, because they provide a basis for longitudinal comparison of the patient’s progress. A “5,” today, is better than an “8,” yesterday. Verbal rating scales (VRSs) present lists or continua of adjectives or descriptors and ask the patient to select the word or words that best describe his or her pain. VRSs typically add a sensory and even a reactive dimension to the assessment of intensity, because many words describing pain are typically affect-laden (e.g., “annoying,” “excruciating,” “unbearable”). The application of these unidimensional measures is widespread, and they are generally held to be useful as indicators of pain intensity, but they offer no valid basis for comparison between patients.

One of the most comprehensive measures of pain intensity, the McGill Pain Questionnaire (MPQ),31 is also one of the oldest and most widely used and cited pencil-and-paper instruments developed for pain. The MPQ presents three classes of pain-related adjectives—sensory, affective, and evaluative—in 20 subclasses or groupings and instructs patients to endorse those words that accurately describe their pain. Scores are then derived for the sensory, affective, and evaluative dimensions of pain, along with a score of intensity from a five-item VRS. Line drawings depicting the front and back views of the body are also presented with instructions to portray the spatial distribution of pain. The MPQ has been criticized for requiring a comparatively high level of reading ability and intelligence, for lacking a consistent scoring technique, for the lengthy administration time, and for problems with construct validity; but it possesses a high content validity and is the measure of pain intensity most widely applied to research. A shorter form of the instrument (SF-MPQ)32 has been developed that correlates highly with the longer version and has a greater ease of administration.

Measures of Coping and Beliefs About Pain

A second category of measures developed for use in chronic pain consists of those instruments devoted to assessing (1) the ways in which patients attempt to cope with pain, as well as the relative success of their coping strategies; and (2) what patients believe about their pain and the ways in which their beliefs influence their responses to pain. The prevailing model of coping, based on the transactional model of stress, suggests that coping is a continuous process in which external and internal demands are managed through constantly changing cognitive and behavioral efforts.33 In effect, patients are always attempting to control or manage stressors, including the experience of their pain, by appraising their situations, reacting, and then reappraising their situations, based on the results of their actions.

Coping is both a conscious and an unconscious process, the characteristic patterns of which may be called a patient’s coping techniques or strategies. Not all of these techniques and strategies are effective, however, and learning more about the ways in a patient is trying to cope with pain can be a critical feature of psychosocial assessment and the planning of interventions. Similarly, what patients believe about their pain—whether deeply rooted philosophical assumptions or dominant attitudes or uncritically accepted superstitions—can contribute greatly to their ongoing experience of pain. Unrealistic or negative thinking can lead to intensified pain perception, increased distress, and a greater sense of suffering and disability. When a patient believes, for example, that further diagnostic procedures will eventually enable clinicians to arrive at an answer for his or her pain, then the idea of effective self-management can be postponed indefinitely. When a patient believes that he or she cannot function productively with his or her pain, then the motivation to become an active participant in treatment is reduced.

There are many available self-report measures of coping and beliefs about pain, including the Coping Strategies Questionnaire (CSQ),34 the Vanderbilt Pain Management Inventory (VPMI),35 the Chronic Pain Coping Inventory (CPCI),36 the Behavioral Assessment of Pain Questionnaire (BAP)37 the Survey of Pain Attitudes (SOPA),38 the Pain Beliefs and Perceptions Inventory (PBAPI),39 the Cognitive Risk Profile (CRP), 40 the Inventory of Negative Thoughts in Response to Pain (INTRP),41 and the already mentioned Pain Stages of Change Questionnaire (PSOCQ).21 Three of the more versatile and widely applied of these measures are summarized in Table 13-2.

Measures of Functional Capacity

One of the most important objectives of pain management is the increase of functional capacity. Is a reduction in pain meaningful if there is no noticeable change in the patient’s level of activity or ability to work or social involvement? Patients with pain describe considerable variation in the degree of interference they experience from distress and impairment; and it is usually a good idea to assess a patient’s perceived level of disability, from the outset of treatment, as well as longitudinally to mark his or her progress. A reliable measure of functional capacity can serve to quantify and cross-validate a patient’s self-report of changes in what he or she can do, as a result of treatment. A number of measures can be used to assess functional capacity, including the West-Haven Yale Multidimensional Pain Inventory (WHYMPI),42 the Chronic Illness Problem Inventory (CIPI),43 the Illness Behavior Inventory (IBI),44 the Sickness Impact Profile (SIP),45 the Short-Form Health Survey (SF-36),46 and the Pain Disability Index (PDI).47 Three of these measures are summarized in Table 13-3.

Measures of Psychopathology Applied to Chronic Pain

Most patients with chronic pain do not present with histories of major psychiatric disorder. Assessing psychopathology and its potential influence on the development and maintenance of pain is, nevertheless, critical for three reasons: (1) chronic pain is far more prevalent among psychiatric populations, (2) the incidence of patients developing comorbid psychiatric symptoms is high, and (3) major psychopathology is associated with poor prognosis in the treatment of chronic pain and disability (see Chap. 14). Some of the more useful measures of psychopathology applied to patients with chronic pain include the Beck Depression Inventory (BDI),48 the Pain Patient Profile (P3),49 the Millon Behavioral Health Inventory (MBHI),50 the Minnesota Multiphasic Personality Inventory (MMPI-2),51 and the Symptom Checklist 90 (SCL-90R).52 Three of these measures are summarized in Table 13-4.

The existence of such a broad array of techniques and measures employed in the psychosocial assessment of chronic pain is compelling evidence of the complexity of the problem. No single approach to diagnosis can discern all that we need to consider about a patient’s experience of pain. Cross-validating clinical impressions with other sets of data from multiple providers is, therefore, critical to the accurate diagnosis and effective treatment of chronic pain. The addition of a psychosocial approach to evaluation can ensure the likelihood of not missing a critical piece of the pain picture. When psychosocial factors are identified as influential in the patient’s history and presentation, a comprehensive evaluation, involving a multidisciplinary team of providers working toward an interdisciplinary synthesis of all the available data, may be the only means of ensuring a sensitive, accurate, and, above all, useful assessment of the patient’s problem.