Disorders of the back and spine in construction workers. Prevalence and prognostic value for disability

STUDY DESIGN: A cohort study on back-related morbidity and its impact on early retirement resulting from disability among employees in the construction industry. OBJECTIVE: To describe the prevalence of back-related morbidity according to different measures in various occupational groups and to assess the prognostic value of these measures for early retirement resulting from disability. METHODS: The results of occupational health examinations conducted in 1986-1988 among 4,958 employees of the German construction industry aged 40-64 years were analyzed. Active follow-up evaluation was carried out between October 1992 and July 1994 to ascertain employment status. RESULTS: Compared with that of white-collar employees, no excess risk for self-reported back pain or sciatica was seen for any of the manual professions. In contrast, the age-adjusted prevalence of clinical findings of the spine was elevated among all employees in manual professions, and the prevalence of a recorded diagnosis related to disorders of the back and spine (ICD-9 position 720-724) was elevated among bricklayers compared with white-collar employees. The relative risk of being granted a disability pension in the follow-up period was 1.6 (95% Confidence Interval [Cl], 1.3-2.1) for persons reporting back pain or sciatica, 1.8 (95% Cl, 1.4-2.2) for persons with an abnormal clinical finding of the spine, and 1.5 (95% Cl, 1.2-1.8) for persons with a recorded medical diagnosis related to disorders of the back or spine (ICD-9 720-724). CONCLUSION: Patterns of morbidity varied according to the evaluated morbidity measure. All three measures qualified as significant predictors of disability and helped to identify high-risk occupations and high-risk employees.     

A population-based, randomized clinical trial on back pain management

STUDY DESIGN: Population-based randomized clinical trial. OBJECTIVES: To develop and test a model of management of subacute back pain, to prevent prolonged disability. SUMMARY OF BACKGROUND DATA: The present management of back pain seems inadequate, and development of innovative models has been urged. METHODS: A model for the treatment of subacute work-related back pain has been developed and evaluated in a population-based randomized clinical trial. Workers (n = 130) from eligible workplaces in the Sherbrooke area (N = 31), who had been absent from work for more than 4 weeks for back pain, were randomized, based on their workplace, in one of four treatment groups: usual care, clinical intervention, occupational intervention, and full intervention (a combination of the last two). The duration of absence from regular work and from any work was evaluated using survival analysis. Functional status and pain were compared at study entry and after 1 year of follow-up. RESULTS: The full intervention group returned to regular work 2.41 times faster than the usual care intervention group (95% confidence interval 1.19-4.89; P < 0.01). The specific effect of the occupational intervention accounted for the most important part of this result, with a rate ratio of return to regular work of 1.91 (95% confidence interval = 1.18-3.10; P < 0.01). Pain and disability scales demonstrated either a statistically significant reduction or a trend toward reduction in the three intervention groups, compared with the trend in the usual care intervention group. CONCLUSIONS: Close association of occupational intervention with clinical care is of primary importance in impeding progression toward chronicity of low back pain.     

Somatization in cross-cultural perspective: a World Health Organization study in primary care

OBJECTIVE: The purpose of this study was to examine the phenomenon of somatization in different cultures by determining its frequency and correlates in primary care settings in 14 countries. METHOD: Consecutive primary care patients (N = 25,916) were screened with the 12-item General Health questionnaire, and a stratified sample (N = 5,438) was interviewed with the Composite International Diagnostic Interview. Interviewed patients were also assessed for physical disease burden, self-rated overall health, physician-rated physical health status, number of disability days, and interviewer-rated occupational role functioning. The authors determined center-specific associations with the use of logistic regression analyses in which confounding variables were controlled. RESULTS: ICD-10 defined somatization disorder was relatively uncommon in most primary care settings. A less restrictively defined form was more common. Symptom rates were much higher in South American sites. There was a modest association with low education. Otherwise, frequency of unexplained somatic symptoms did not clearly vary according to geography or level of economic development. Somatizing patients were at elevated risk for self-reported disease burden, negative perception of their health, and comorbid depression and generalized anxiety disorder. Somatization was also commonly associated with disability. Cultures did not differ markedly in the pattern of these associated features. CONCLUSION: Somatization is a common problem in primary care across cultures and is associated with significant problems and disability.     

Effect of blood viscosity on the function of isolated perfused porcine kidney after cold preservation

STUDY DESIGN: Cross-sectional study with two age cohorts. OBJECTIVE: To assess whether women receiving hormone replacement therapy after menopause have a higher prevalence of back problems than women who do not receive such treatment. BACKGROUND: Back pain is a common medical problem throughout life and especially during pregnancy. Hormonal factors have been proposed as a possible contributor. PATIENTS AND METHODS: A validated postal questionnaire was sent in early 1995 to all 1324 women of 55 years and 56 years of age residing in Link?ping, Sweden. This questionnaire included questions about current hormone replacement treatment, previous and current back problems, medical care for back problems, parity, exercise and smoking habits, and occupation. RESULTS: The questionnaire was returned by 84.7% of the women. There was a significant, albeit weak, positive association between current use of hormone replacement treatment and low back pain. Previous back problems during pregnancy was a strong risk factor for current back pain, whereas neither current smoking nor regular physical exercise was a risk factor according to multiple logistic regression analysis. The interaction of smoking and an occupation involving heavy lifting significantly affected back pain. CONCLUSIONS: Women receiving hormone replacement treatment had a slightly, but significantly, higher prevalence of current back pain than nonusers (48% vs. 42%, respectively, P < 0.05), which could not be explained by differences in occupation, smoking habits, or current physical activity. Although the association between hormone replacement therapy and back problems is weak and probably of minor clinical importance, it is speculated that hormonal effects on joints and ligaments may be involved.     

Chronic posttraumatic stress disorder and chronic pain in Vietnam combat veterans

A study was conducted to investigate chronic pain patterns in Vietnam veterans with posttraumatic stress disorder (PTSD). Combat veterans with PTSD completed standardized PTSD severity, pain, somatization, and depression measures. Of 129 consecutive out-patient combat veterans with PTSD, 80% reported chronic pain. In descending order were limb pain (83%), back pain (77%), torso pain (50%), and headache pain (32%). Compared to PTSD combat veterans without chronic pain, PTSD veterans who reported chronic pain reported significantly higher somatization as measured by the Minnesota Multiphasic Inventory 2 hypochondriasis and hysteria subscales. In the sample of 103 combat veterans with PTSD and chronic pain, MMPI 2 hypochondriasis scores and B PTSD symptoms (reexperiencing symptoms) were significantly related to pain disability, overall pain index, and current pain level MMPI 2 hypochondriasis and depression scores were also significantly related to percent body pain. These results are discussed in the context of current conceptualizations of PTSD.     

Giant congenital nevocellular nevus overlying an encephalocele

OBJECTIVE: To compare patients with knee osteoarthritis (OA) who have and do not have back pain, and evaluate the prevalence, characteristics, and consequences of back pain among knee OA patients. METHODS: During a 3-year period, consecutive patients attending an outpatient rheumatology clinic were evaluated for the presence of back pain, and 368 were found to have OA of the knee. Clinical status was evaluated by the Clinical Health Assessment Questionnaire, radiographs, and joint examinations. RESULTS: Back pain was present in 54.6% of patients with OA of the knee. Almost every clinical status measure was worse among those reporting back pain, including Health Assessment Questionnaire (HAQ) disability, pain, global severity, fatigue, and psychological status. Back pain was more common in women and the obese, but was not associated with age, marital status, formal education, smoking history, or knee radiographic scores. In multivariate analyses the strongest correlates of back pain in knee OA patients were anxiety, night pain, HAQ disability, and global severity. CONCLUSION: Back pain is prevalent among OA clinic patients, more common than in rheumatoid arthritis or population studies, is linked to body mass index, and is associated with clinically significant increases in pain and other measures of clinical distress.     

Early physician notification of patient disability risk and clinical guidelines after low back injury: a randomized, controlled trial

STUDY DESIGN: Back-injured workers with high disability risk scores on a predictive questionnaire participated in a randomized, controlled trial of physician notification, with outcomes follow-up 3 months after injury. OBJECTIVES: To test whether physician intervention improves return to work and self-assessment outcomes for people at relatively high risk for disability. SUMMARY OF BACKGROUND DATA: Only a small number of back-injured workers suffer significant disability. Quick identification of these people would facilitate more efficient targeting and trials of interventions. Controlling variations in practice through practice guidelines has been recommended as a promising strategy for improving care and reducing disability. METHODS: Workers filing back injury reports responded to a disability prediction questionnaire. Those with high risk scores were randomly assigned to control or intervention groups. Patient-designated physicians in the intervention group received two letters identifying the patient's risk and making recommendations for care, including the Agency for Health Care Policy and Research's algorithms for acute low back pain. Predictive accuracy of the questionnaire and efficacy of physician intervention were evaluated on the basis of work status and self-assessments 3 months after injury. RESULTS: Of the 268 workers completing the questionnaire portion of the study, 32 (12%) were out of work because of back pain 3 months after injury. The questionnaire's predictive accuracy included maximum kappa of 0.277 and a receiver operating curve area of 0.78. Fifty-three people completed the physician intervention trial. The intervention had no significant impact on return to work, self-assessed pain, or satisfaction with health care. CONCLUSIONS: Stratification of back-injured people according to disability risk can can increase intervention efficiency by identifying those who require treatment and sparing those who do not. The apparent failure of risk notification and practice guidelines to reduce disability in this study may be improved by different application methods in the future.     

Psychosocial issues: their importance in predicting disability, response to treatment, and search for compensation

The conceptualization of pain and its progression into chronic disability has evolved from unidimensional models to more integrative, biopsychosocial models that take into account the many biological, psychosocial, social, and economic factors that may significantly contribute to the low back pain experience. This chapter reviews various studies that have demonstrated our growing understanding of these complex, interactive processes in helping to predict those who develop chronic disability as well as those who respond best to treatment attempts. Further, we examine the issue of compensation and how it too is intricately intertwined with the other variables contributing to lower back pain disability.     

Construction of vectors expressing bioactive heterodimeric and single-chain murine interleukin-12 for gene therapy

OBJECTIVE: We examined the prevalence, correlates, and predictive value of an abbreviated somatization index, based on specific symptom thresholds, in primary care patients using services at a university-affiliated clinic. METHOD: We interviewed 1456 patients with a survey instrument that included the Composite International Diagnostic Interview (CIDI) to elicit symptoms and diagnoses of several psychiatric disorders as well as demographic information and a measure of disability. Statistical analyses examined the relationship of abridged somatization with physical functioning and various demographic and diagnostic factors. RESULTS: About one fifth of this primary care sample met the abridged somatization criteria. "Somatizers," defined according to these criteria, had significantly higher levels of psychiatric comorbidity and disability than "nonsomatizers". Analyses taking into account the number and type of organ/body systems represented by the unexplained symptoms showed that this dimension adds specificity to the prediction of outcomes. Thus, regardless of the total number of medically unexplained symptoms, abridged somatization with unexplained symptoms attributable to four or more organ/body systems showed the strongest association with disability and psychopathology. CONCLUSIONS: Abridged Somatization is a frequent syndrome in primary care that is strongly associated with psychopathology and physical disability. Our research also yielded a new series of abridged somatization subtypes (eg, "discrete" vs. "comorbid" and "simple" vs. "polymorphous") that may effectively separate among various psychopathologies, and may become useful tools for future research with somatizing patients.     

Sexual and physical abuse in women with fibromyalgia: association with outpatient health care utilization and pain medication usage

OBJECTIVE: To evaluate the relationship between sexual and/or physical abuse and health care usage in patients with fibromyalgia (FM) and identify variables that may influence this relationship. METHODS: We assessed history of sexual/physical abuse, health care utilization, and medication usage, as well as related variables in 75 women with FM using standardized questionnaires, structured interviews, and laboratory pain perception tasks. RESULTS: Fifty-seven percent of FM patients reported a history of sexual/physical abuse. Compared to non-abused patients, abused patients reported significantly greater utilization of outpatient health care services for problems other than FM and greater use of medications for pain (P < or = 0.025). Consistent with our expectations, abused patients also were characterized by significantly greater pain, fatigue, functional disability, and stress, as well as by a tendency to label dolorimeter stimuli as painful regardless of their intensities (P < or = 0.05). Additional analyses suggested that the high frequency of sexual/physical abuse in our patients was associated primarily with seeking health care for chronic pain rather than the FM syndrome itself or genetic factors. CONCLUSION: There is an association in FM patients between sexual/physical abuse and increased use of outpatient health care services and medications for pain. This association may be influenced by clinical symptoms, functional disability, psychiatric disorders, stress, and abnormal pain perception. The relationships among these variables should be further tested in prospective, population-based studies.     

Natural history of low back pain. A longitudinal study in nurses

STUDY DESIGN: Longitudinal study. OBJECTIVES: To assess the natural history of low back pain. SUMMARY OF BACKGROUND DATA: Most episodes of low back pain resolve or improve within a few weeks, but chronic or recurrent symptoms are common. Previous studies of natural history have usually relied on people's long-term recall of symptoms, or they have been limited to patients seeking clinical care. METHODS: Nurses (1,165 women) completed a baseline questionnaire and up to eight follow-up questionnaires 3 months apart. Each questionnaire asked whether they had experienced low back pain in the past month. One-month prevalences of pain at specified follow-ups were calculated according to histories of pain reported on earlier questionnaires. RESULTS: The 1-month prevalence of low back pain at individual follow-ups ranged from 16% to 19%. Of 906 women who completed the baseline questionnaire and at least three follow-up questionnaires, 38 (4.2%) reported pain every time they returned a questionnaire, and 190 (21.0%) reported pain on at least three occasions. The presence or absence of low back pain at baseline was highly predictive of future pain throughout follow-up. The longer that back pain was consistently reported, the more likely it was to be present at the next follow-up. Later risk was lowest in women who reported no back pain at baseline or either of the first two follow-ups. Back pain carried a worse prognosis if it was disabling or associated with sciatica. CONCLUSIONS: Our results confirm the importance of back pain duration and the occurrence of associated disability and sciatica as predictors of future symptoms, and allow more reliable quantification of the natural history of back pain in women of working age. In the absence of other information, the differentials in risk associated with a person's history of back pain appear to remain constant for a period of at least 2 years.     

Epidemiologic study on the prevalence of low back pain in health personnel exposed to manual handling tasks]

An epidemiological study on the prevalence rate of low back pain among health care workers exposed to manual handling tasks and physical work load was performed. A representative sample (n. 1053) of nursing staff working at the San Matteo Hospital in Pavia was studied using a questionnaire with the purpose of evaluating the prevalence rate of low back pain and related risk factors. 86.4% of the subjects admitted having suffered from back pain at some stage in their life and 71.0% complained of back pain in the 3 months prior to answering the questionnaire. Multivariate logistic regression analysis revealed a significant correlation between low back pain, female gender and specific nursing activities. A significant correlation was found between smoking (> 20 cigarettes per day) and the presence of low back pain, due to intervertebral disk pathology. A statistically significant difference (p < 0.0001) was found in the average degree of disability between healthy nurses (1.3), those with low back pain taking analgesic drugs (5.9) and nurses suffering from low back pain without taking drugs (3.8).     

Increase of non-amidated muropeptides in the cell wall of vancomycin-resistant Staphylococcus aureus (VRSA) strain Mu50

BACKGROUND: In previous survey we found large socioeconomic differences in mortality among urban Swedish men which remained unexplained after controlling for smoking and standard coronary risk factors. The present analysis was undertaken in order to investigate a broader set of possible explanatory factors in another cohort of Swedish men. STUDY POPULATION AND METHODS: Occupation was coded into five occupational classes for 717 of 776 participant men from a random population sample of 1016 men who were born in 1933. All were living in G?teborg and were 50 years old at the baseline examination. After 12 years' follow-up, 68 of the 717 men had died (9.5%). RESULTS: Low occupational class was associated with a higher prevalence of smoking at baseline, but no association was found with systolic blood pressure, body mass index, waist to hip ratio, serum triglycerides or serum cholesterol. Subjects from higher socioeconomic strata were taller, had higher maximum peak respiratory flow, lower plasma fibrinogen and lower body temperature. Low occupational class was associated with low social integration, low home activity levels, low levels of activity outside home and low social activity levels (p = 0.001 for all) and with low emotional support (p = 0.018). There were also associations between low occupational class and poor self-perceived health, as well as with several cardiovascular symptoms. During 12 years' follow-up, there was a graded and inverse relationship between occupational class and mortality from all causes. The highest mortality was found among the men who could not be classified (23 per 1,000 person years) Of the men in the lowest occupational class, 12 per 1,000 died, compared to 3 per 1,000 in the highest class (relative risk 3.7 (1.4-9.8)). After controlling for smoking, the relative risk decreased to 3.2 (1.2-8.6) and after further adjustment for emotional support, self-perceived health, activity level at home, and peak expiratory flow, the relative risk was still twofold but not significantly so (RR 2.1 (0.8-5.8)). CONCLUSION: We were able to confirm earlier results as to the wide mortality differentials in urban middle-aged men in Sweden. There were also large differences in several other factors, including constitutional factors, health variables, lifestyle and social support indices, which explained important parts of the social mortality gradient, the most prominent being smoking, respiratory function, social network factors and subjective health.     

The effect of compensation involvement on the reporting of pain and disability by patients referred for rehabilitation of chronic low back pain

STUDY DESIGN: In this prospective, observational, cohort study of 192 individuals with chronic low back pain, the group of individuals was divided based on compensation involvement, and their presentation pain and disability, treatment recommendations, and compliance were compared. For 85 of these individuals who completed a spine rehabilitation program, their pain and disability at 3 and 12 months were compared. OBJECTIVES: To test the theory that individuals with compensation involvement presented with greater pain and disability and would report less change of pain and disability after rehabilitation efforts. BACKGROUND: Previous studies have produced conflicting results concerning this issue. METHODS: Individuals were recruited as consecutive patients referred for consultation at a spine rehabilitation center. Pain, depression, and disability were assessed using self-report questionnaires at evaluation and at 3 and 12 months. Rehabilitation services consisted of aggressive, quota-based exercises aimed at correcting impairments in flexibility, strength, endurance, and lifting capacity, identified through quantification of back function. Multifactoral analysis of variance models were used to control for baseline differences between compensation and noncompensation patients during analysis of target variables. RESULTS: The compensation group included 96 patients; these patients reported more pain, depression, and disability than the 96 patients without compensation involvement. These differences persisted when baseline differences were controlled for with multifactoral analysis of variance models. Treatment recommendations and compliance were not affected by compensation. For patients completing the spine rehabilitation program, length of treatment, flexibility, strength, lifting ability, and lower extremity work performance before and after treatment and patient satisfaction ratings were similar for the compensation and noncompensation groups. At 3 and 12 months, improvements in depression and disability were noted for both groups, but were statistically and clinically less substantial for the compensation group. At the 12 month follow-up visit, pain scores improved for the noncompensation group, but not for the compensation group. CONCLUSIONS: In chronic low back pain, compensation involvement may have an adverse effect on self-reported pain, depression, and disability before and after rehabilitation interventions.     

Chronic low back pain: Toward an integrated psychosocial assessment model.

Reports on the integration of 6 dimensions of chronic low back pain to provide a multidimensional profile of the patient. These dimensions were pain intensity, functional disability, attitudes toward pain, pain coping strategies, depression, and illness behavior. Cluster analysis of the data obtained from 100 patients with chronic low back pain revealed the presence of 3 distinct patient groups: patients who were in control, patients who were depressed and disabled, and patients who were active copers with high denial. The validity of these clusters was supported by significance testing on several external variables. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Outpatient group treatment of chronic pain: Effects of spouse involvement.

Evaluated the efficacy of outpatient group treatment of chronic pain and the effect of spouse involvement in treatment in chronic pain patients ranging in age from 23 to 69 yrs who were randomly assigned to couples group treatment (n?=?17), patient-only group treatment (n?=?14), or waiting-list controls (n?=?12). 29 Ss had low back pain; the remaining Ss reported pain in the knee, arm, leg, hip, head, and phantom limb. The Ss completed the MMPI—168 and measures of health-related psychosocial and physical dysfunction and marital satisfaction. Results indicate that the 16-hr cognitive-behavioral program produced reductions in pain, somatization, spouse-observed pain behavior, physical and psychosocial dysfunction, spouse-rated dysfunction, and utilization of health care resources. Depression was not affected by treatment. Spouse involvement did not facilitate response to treatment on any variables. Also, Ss in the individual condition only showed improved marital satisfaction. All treatment gains were maintained at 3-mo to 7-mo follow-ups. Results indicate that brief outpatient treatment can significantly ameliorate chronic pain problems, and spouse involvement is not essential for a positive response to treatment. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preterm delivery: effects of socioeconomic factors, psychological stress, smoking, alcohol, and caffeine

OBJECTIVE: To examine the relation between preterm birth and socioeconomic and psychological factors, smoking, and alcohol, and caffeine consumption. DESIGN: Prospective study of outcome of pregnancy. SETTING: District general hospital in inner London. PARTICIPANTS: 1860 consecutive white women booking for delivery; 1513 women studied after exclusion because of multiple pregnancy and diabetes, refusals, and loss to follow up. MEASUREMENTS: Gestational age was determined from ultrasound and maternal dates; preterm birth was defined as less than 37 completed weeks. Independent variables included smoking, alcohol and caffeine consumption, and a range of indicators of socioeconomic status and psychological stress. MAIN RESULTS: Unifactorial analyses showed that lower social class, less education, single marital status, low income, trouble with "nerves" and depression, help from professional agencies, and little contact with neighbours were all significantly associated with an increased risk of preterm birth. There were no apparent effects of smoking, alcohol, or caffeine on the length of gestation overall, although there was an association between smoking and delivery before 32 weeks. Cluster analysis indicated three subgroups of women delivering preterm: two predominantly of low social status and a third of older women with higher social status who did not smoke. Mean gestational age was highest in the third group. CONCLUSIONS: Adverse social circumstances are associated with preterm birth but smoking is not, apart from an association with very early births. This runs counter to findings for fetal growth (birth weight for gestational age) in this study, where a strong effect of smoking on fetal growth was observed but there was no evidence for any association with psychosocial factors.     

Cognitive distortion and psychological distress in chronic low back pain.

Examined the association of cognitive distortion with 5 Minnesota Multiphasic Personality Inventory (MMPI) scales—Depression (D), Psychasthenia (Pt), Schizophrenia (Sc), Hypochondriasis (Hs), and Hysteria (H)—in 138 depressed, chronic low back pain patients (mean age 39.9 yrs). Ss completed a cognitive error questionnaire, the MMPI, a sickness impact profile, and daily pain diaries. Results indicate that cognitive distortion was associated with high scores on the D, Pt, and Sc scales but not the Hs and Hy scales. Thus, cognitive distortion is likely to be an important factor in general distress but not in somatization among back pain patients. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental disorders and disability among patients in a primary care group practice

OBJECTIVE: This article examines social and occupational disability associated with several DSM-IV mental disorders in a group of adult primary care outpatients. METHOD: The subjects were 1,001 primary care patients (aged 18-70 years) in a large health maintenance organization. Data on each patient's sociodemographic characteristics and functional disability, including scores on the Sheehan Disability Scale, were collected at the time of a medical visit. A structured diagnostic interview for current DSM-IV disorders was then completed by a mental health professional over the telephone within 4 days of the visit. RESULTS: The most prevalent disorders were phobias (7.7%), major depressive disorder (7.3%), alcohol use disorders (5.2%), generalized anxiety disorder (3.7%), and panic disorder (3.0%). A total of 8.3% of the patients met the criteria for more than one mental disorder. The proportion of patients with co-occurring mental disorders varied by index disorder from 50.0% (alcohol use disorder) to 89.2% (generalized anxiety disorder). Compared with patients who had a single mental disorder, patients with co-occurring disorders reported significantly more disability in social and occupational functioning. After adjustment for other mental disorders and demographic and general health factors, compared with patients with no mental disorder, only patients with major depressive disorder, bipolar disorder, phobias, and substance use disorders had significantly increased disability, as measured by the Sheehan Disability Scale. CONCLUSIONS: Primary care patients with more than one mental disorder are common and highly disabled. Individual mental disorders have distinct patterns of psychiatric comorbidity and disability.     

The effects of medical evidence and pain intensity on medical student judgments of chronic pain patients

This study examined symptom judgments made by medical students of hypothetical chronic low back pain patients. Eight vignettes were varied as to the pain intensity reported by the hypothetical patient (low vs. moderate vs. high vs. very high) and the availability of medical evidence supportive of the pain report (present vs. absent). Ninety-five subjects read vignettes and made judgments of patient emotional distress, pain intensity, and pain-related disability. Subjects significantly discounted pain level when intensity was high but slightly augmented pain level when intensity was low. Judgments of pain and disability were higher for patients for whom medical evidence was present compared to those for whom it was absent. The results support and extend previous research on the effects of situational and patient variables on observer pain judgments. Future research should examine the influence of these biasing variables on the assessment and treatment of chronic pain patients.