Raymond C. Tait

The Pain Disability Index: psychometric properties.

&NA; This paper reports two studies of chronic pain patients (n = 444) relevant to the psychometric properties of the Pain Disability Index (PDI), a self‐report instrument that has been used to assess the degree to which chronic pain interferes with various daily activities. In the first study, patients with high PDI scores reported more psychological distress (P < 0.001), more severe pain characteristics (P < 0.001), and more restriction of activities (P < 0.001) than patients with low PDI scores, findings supportive of the construct validity of the measure. Further, a multiple regression showed that a linear combination of 9 variables predicted PDI scores (R = 0.74): time spent in bed, psychosomatic symptoms, stopping activities because of pain, work status, pain duration, usual pain intensity, quality of life, pain extent, and education. This study also showed differences for age and gender on disability. The second study involved 46 patients who had undergone inpatient treatment for their pain conditions. The study revealed modest test‐retest reliability for the instrument. It also showed the PDI to be associated with the levels of pain behavior exhibited by these patients. The findings of both studies generally support the reliability and validity of the PDI as a brief measure of pain‐related disability. Questions regarding its test‐retest reliability and lack of association with certain pain behaviors are discussed, as are suggestions for future research.

An interdisciplinary expert consensus statement on assessment of pain in older persons

This paper represents an expert-based consensus statement on pain assessment among older adults. It is intended to provide recommendations that will be useful for both researchers and clinicians. Contributors were identified based on literature prominence and with the aim of achieving a broad representation of disciplines. Recommendations are provided regarding the physical examination and the assessment of pain using self-report and observational methods (suitable for seniors with dementia). In addition, recommendations are provided regarding the assessment of the physical and emotional functioning of older adults experiencing pain. The literature underlying the consensus recommendations is reviewed. Multiple revisions led to final reviews of 2 complete drafts before consensus was reached.

a rating system for use with patient pain drawings

&NA; Patients entering treatment for chronic benign pain often are asked to complete drawings indicating the intensity and location of their pain as part of the diagnostic process. While inferences have been made from pain drawings about the relative contributions of physiological and psychological factors to the patients experience of pain, previous research has provided only equivocal support for this practice. A reliable method for assessing pain drawings is needed both for clinical use and to assess the validity of such interpretations. While a number of systems for using such drawings have been proposed, it is not always clear exactly what aspect of the drawing is being quantified. In this study, 101 patients who presented with chronic pain were asked to complete pain drawings which were than scored for the presence or absence of pain in each of 45 body areas. Scorers achieved a high rate of inter‐rater agreement with relatively little training. The body surface scores obtained were shown to correlate highly with the penalty point system developed by Ransford et al., suggesting that extent of pain may account for much of the variance in this system. The results are discussed in relation to the clinical and experimental uses for such a system.

The Pain Disability Index: Factor Structure and Normative Data

The factor structure and normative data for the Pain Disability Index (PDI) were examined in a large (N = 1,059) sample of chronic pain patients. The results support a one-factor solution for the PDI. Analyses of normative data indicated very small effects associated with gender, age, and pain duration. Relatively larger effects were associated with compensation status, litigation status, and circumstances of pain onset. Working patients reported less disability than their nonworking counterparts, litigating patients reported more disability than nonlitigants, and patients injured at work reported higher levels of disability than those with pain origins unrelated to work. The results reflect the disability level of patients referred to a hospital-based pain management program and may be useful as a reference point when comparing disability levels of other patient groups or research samples.

Pain assessment in cognitively impaired and unimpaired older adults: a comparison of four scales.

&NA; The purpose of the study was to compare the psychometric properties of four established pain scales in a population of hospitalized older adults (mean age, 76 years) with varying levels of cognitive impairment. Patients made ratings of current pain three times/day for 7 days. They also made retrospective daily, weekly, and bi‐weekly ratings of usual, worst, and least pain levels over a 14‐day period. Ratings were made on four different scales, varying in numeric and verbal demands: a five‐point verbal rating scale, a seven‐point faces pain scale, a horizontal 21‐point (0–100) box scale, and two vertical 21‐point (0–20) box scales (measuring pain intensity and pain unpleasantness). The accuracy, reliability, construct validity, postdictive validity, and bias susceptibility of each scale were evaluated. The horizontal 21‐point box scale emerged as the best scale with respect to both psychometrics and validity, regardless of mental status. Pain intensity did not vary as a function of mental status. Retrospective estimates of pain varied by mental status: a combination of usual/worst pain was best for cognitively impaired patients, while a combination of usual/least pain was best for unimpaired patients. These findings support the use of the 21‐point box scale for pain assessment in older patients, including those with mild‐to‐moderate cognitive impairment. They also support the ability of older, cognitively impaired patients to rate pain reliably and validly.

Test-retest reliability of the pain drawing instrument

&NA; Test‐retest reliability of a pain drawing instrument was investigated. Pain drawings of chronic pain patients (n = 51) were scored for percentage of total body surface in pain and location of pain. A test‐retest reliability coefficient of r = 0.85 was calculated for a time interval that averaged 71 days. In addition, a percentage of agreement based on distribution of pain over time was calculated at 88.2%. The effect on reliability of age, gender and time‐interval differences was investigated. The utility of the pain drawing instrument as a measure of extent of pain and location of pain over time is discussed.

Physician judgments of chronic pain patients

Recent evidence has indicated that physician judgments of patients can be influenced by contextual factors. This study examined three contextual factors relevant to hypothetical patients with low back pain, using vignettes that were varied in a 2 x 2 x 2 factorial design: level of reported pain (high vs low), level of supporting medical evidence (high vs low), and the valence of the physician-patient interaction (positive vs negative). Perceived levels of pain, disability, emotional distress, and somatic preoccupation were rated by internists after reading a vignette. Ratings of pain and disability were lower for patients without supporting medical evidence; ratings of distress, somatic preoccupation, and disability were greater for patients who exhibited negative rather than positive affect; internist ratings of pain were lower than patient ratings among patients reporting high levels of pain, while ratings were inflated for patients with low levels of pain. The results suggest that characteristics of both the patient and the situation may influence medical judgments.

Provider Judgments of Patients in Pain: Seeking Symptom Certainty

OBJECTIVE Uncertainty often surrounds judgments of pain, especially when pain is chronic. In order to simplify their decisions, providers adduce information from a variety of sources. Unfortunately, an extensive literature suggests that the information that is brought to bear actually can bias pain judgments, resulting in judgments that consistently differ from patient reports, with a potential negative impact on treatment. METHODS This review examines the pain assessment literature from a social cognition perspective that emphasizes interpersonal and situational factors that can influence judgments. Consistent with that model, it organizes research findings into three broad domains that have been shown to systematically influence assessments of pain, involving patient, provider, and situational factors. RESULTS A causal model for pain judgment is proposed, and its implications for clinical research and practice are explored. CONCLUSIONS In order to minimize the uncertainty that can characterize symptoms such as chronic pain, practitioners bring information to bear on pain assessment that can lead to misjudgments. While intuitively appealing, much of the information that is considered often has little association with pain severity and/or adjustment. A more rational decision-making process can reduce the judgment errors common to pain assessment and treatment.

Relationship between social desirability and self-report in chronic pain patients

Objective:To examine the relationship between social desirability and self- report in data collected from chronic pain patients. Setting:A multidisciplinary pain management center located in a major university medical center. Patients:Two hundred persons presenting with chronic pain, including low back, head/neck, and extremity pain. Measures:Marlowe-Crowne Social Desirability Scale, Beck Depression Inventory—Short Form, Spielberger Trait Anxiety Inventory, Psychosomatic Symptom Checklist, McGill Pain Questionnaire, Pain Disability Index, Quality of Life Scale, Pain Drawing. Results and Conclusions:Correlations showed that patients with greater social desirability response bias reported less depression and anxiety but higher levels of pain severity. When depression effects were controlled in a regression analysis, social desirability correlated positively with self-reported disability. These results show systematic response patterns associated with social desirability, suggesting that social desirability response biases should be considered in both research and clinical assessments of chronic pain patients.

Development of a brief version of the Survey of Pain Attitudes.

Abstract Because patient attitudes and beliefs about pain have been shown to affect treatment outcomes and adjustment to illness, a number of self‐report instruments have been developed assess those constructs. The Survey of Pain Attitudes (SOPA) is a well‐researched instrument that assesses patient feelings about pain control, solicitude (solicitous responses from others in response to ones pain), medication (as appropriate treatment for pain), pain‐related disability, pain and emotions (the interaction between emotions and pain), medical cures for pain, and pain‐related harm (pain as an indicator of physical damage or harm). The factor structure of the SOPA, however, has not been verified and its length makes its administration cumbersome. The present study examined the factor structure of the SOPA and developed a brief 30‐item version of the original. Factor analysis showed that the SOPA did not contain seven unique dimensions. The brief version (the SOPA‐B), however, clearly reflected the seven dimensions described for the SOPA. The psychometric properties of the SOPA‐B were comparable to those of the SOPA. The SOPA‐B appears to be a practical, easily‐administered alternative to the longer version.