Validation of CARE Scale-7 in treatment-seeking patients with chronic pain: measurement of sex invariance.

OBJECTIVES: Social and interpersonal factors impact the trajectory of chronic pain. We previously developed and validated a 2-factor, 7-item measure to assess interpersonal factors, including relationship guilt and worry and difficulty prioritizing self-care in chronic pain. Here, we confirm the factor structure and examine the sex invariance of the two-factor structure of the CARE Scale-7. METHODS: Data were collected as part of routine clinical care at a tertiary pain clinic using the Collaborative Health Outcomes Information Registry. Patient participants (67% women) were predominantly middle-aged (M = 50.9 years, SD = 17.8), married (55.2%), and White/non-Hispanic (55.7%). Data included demographics, pain characteristics, CARE Scale-7, pain catastrophizing, and Patient-Reported Outcomes Measurement Information System psychological and physical function measures. Confirmatory factor analysis was conducted to validate the factor structure of the CARE Scale, and a stepwise approach to measurement invariances by sex examined configural, metric, and scalar invariance. RESULTS: Internal consistency of the scale items ensured suitability for factor analyses. Confirmatory factor analysis findings revealed an overall good fit of the 2-factor model among males and females and that CARE Scale-7 is in fact sex invariant. Finally, CARE Scale-7 showed convergent validity with pain-related outcomes. DISCUSSION: The CARE Scale is the first validated instrument to assess self-care in both sexes among patients with chronic pain. The subscale of difficulty prioritizing self-care emerged as a potentially unique factor that should be integrated in clinical assessment. CARE Scale may facilitate standardized measurement in research and clinical contexts, which may inform a comprehensive treatment focus that integrates individualized self-care planning.

Evaluation of the Preliminary Validity of Misuse of Prescription Pain Medication Items from the Patient-Reported Outcomes Measurement Information System (PROMIS)®.

OBJECTIVE: The National Institutes of Health's Patient-Reported Outcomes Measurement Information System (PROMIS)® includes an item bank for measuring misuse of prescription pain medication (PROMIS-Rx Misuse). The bank was developed and its validity evaluated in samples of community-dwelling adults and patients in addiction treatment programs. The goal of the current study was to investigate the validity of the item bank among patients with mixed-etiology chronic pain conditions. METHOD: A consecutive sample of 288 patients who presented for initial medical evaluations at a tertiary pain clinic completed questionnaires using the open-source Collaborative Health Outcomes Information Registry. Participants were predominantly middle-aged (M [SD] = 51.6 [15.5] years), female (62.2%), and white/non-Hispanic (51.7%). Validity was evaluated by estimating the association between PROMIS-Rx Misuse scores and scores on other measures and testing the ability of scores to distinguish among risk factor subgroups expected to have different levels of prescription pain medicine misuse (known groups analyses). RESULTS: Overall, score associations with other measures were as expected and scores effectively distinguished among patients with and without relevant risk factors. CONCLUSION: The study results supported the preliminary validity of PROMIS-Rx Misuse item bank scores for the assessment of prescription opioid misuse in patients visiting an outpatient pain clinic.

Childhood Adversity and Pain Sensitization.

OBJECTIVE: Childhood adversity is a vulnerability factor for chronic pain. However, the underlying pain mechanisms influenced by childhood adversity remain unknown. The aim of the current study was to evaluate the impact of childhood adversity on dynamic pain sensitivity in young adults. METHODS: After screening for childhood adverse events and health status, healthy individuals reporting low (below median; n = 75) or high levels of adversity (the top 5%; n = 51) were invited for pain testing. Both groups underwent heat pain threshold and temporal summation of second pain (TSSP) testing after reporting depressive symptoms. TSSP refers to a progressive increase in pain intensity with repetition of identical noxious stimuli and is attributed to central sensitization. Changes in pain ratings over time (slope) were computed for TSSP sensitization and decay of subsequent aftersensations. RESULTS: The high-adversity group showed greater TSSP sensitization (meanslope, 0.75; SDpositive slope, 1.78), and a trend toward a slower decay (meanslope, -11.9; SD, 3.4), whereas the low-adversity group showed minimal sensitization (meanslope, 0.07; SDnear-zero slope, 1.77), F(1,123) = 5.84, p = .017 and faster decay (meanslope, -13.1; SD, 3.4), F(1,123) = 3.79, p = .054. This group difference remained significant even after adjusting for adult depressive symptoms (p = .033). No group difference was found in heat pain threshold (p = .85). Lastly, the high-adversity group showed blunted cardiac and skin conductance responses. CONCLUSIONS: These findings suggest that enhancement of central sensitization may provide a mechanism underlying the pain hypersensitivity and chronicity linked to childhood adversity.