Characterizing phenotypes and clinical and health utilization associations of young people with chronic pain: latent class analysis using the electronic Persistent Pain Outcomes Collaboration database.

ABSTRACT: Using the Australiasian electronic Persistent Pain Outcomes Collaboration, a binational pain registry collecting standardized clinical data from paediatric ePPOC (PaedsePPOC) and adult pain services (AdultePPOC), we explored and characterized nationally representative chronic pain phenotypes and associations with clinical and sociodemographic factors, health care utilization, and medicine use of young people. Young people ≥15.0 and <25.0 years captured in PaedePPOC and AdultePPOC Australian data registry were included. Data from 68 adult and 12 paediatric pain services for a 5-year period January 2018 to December 2022 (first episode, including treatment information) were analysed. Unsupervised latent class analysis was applied to explore the existence of distinct pain phenotypes, with separate models for both services. A 3-phenotype model was selected from both paediatric and adult ePPOC data, with 693 and 3518 young people included, respectively (at least one valid indicator variable). Indicator variables for paediatric models were as follows: pain severity, functional disability (quasisurrogate "pain interference"), pain count, pain duration, pain-related worry (quasisurrogate "catastrophizing"), and emotional functioning; and, for adult models: pain severity, pain interference, pain catastrophizing, emotional functioning, and pain self-efficacy. From both services, 3 similar phenotypes emerged ("low," "moderate," "high"), characterized by an increasing symptom-severity gradient in multidimensional pain-related variables, showing meaningful differences across clinical and sociodemographic factors, health service utilization, and medicines use. Derived phenotypes point to the need for novel care models that differentially respond to the needs of distinct groups of young people, providing timely, targeted, age-appropriate care. To effectively scale such care, digital technologies can be leveraged to augment phenotype-informed clinical care.

Lessons identified from applications of the Risk Analysis Quality Test Release 1.0.

The Risk Analysis Quality Test Release 1.0 (RAQT1.0) was developed as a framework to encourage mutual understanding between technical risk analysts and risk management decision makers of risk assessment quality indicators. The initial version (release 1.0) was published by the Society for Risk Analysis (SRA) in 2020 with the intent of learning from early test applications whether the approach was useful and whether changes in approach or contents would be helpful. The results of applications across three diverse fields are reported here. The applications include both retrospective evaluations of past risk assessments and prospective guidance on the design of future risk assessment projects or systems. The fields represented include Quantitative Microbial Risk Assessment, Cultural Property Risk Analysis, and Software Development Cyber Risk Analysis. The RAQT1.0 proved helpful for identifying shortcomings in all applications. Ways in which the RAQT1.0 might be improved are also identified.

Short waits, happy patients and expert care, moving basic musculoskeletal care from the emergency department to a physiotherapist-led diversion pathway.

OBJECTIVE: Patients with musculoskeletal conditions (MSKCs) are highly prevalent in ED. This project explores the impact of the pilot phase of a 'diversion pathway', which directed patients with MSKCs from the ED waiting room to an outpatient clinic led by advanced-scope physiotherapists. METHODS: A prospective intervention study comparing care outcomes between patients in the 'diversion pathway' with usual ED care. The characteristics of patients considered eligible and non-eligible are described. RESULTS: Between May and December 2022, 1099 patients were diverted. For diverted patients, mean length of stay (LOS) in ED was reduced by 110 (95% confidence interval [CI]: 99-120) min and 4 h rule compliance improved by 19.3% compared to usual ED care. There were fewer patients who 'did not wait' (DNW) with the diversion pathway. The diverted group was young (median age 22 years and 41% paediatric), mostly low urgency, self-referred and arrived by private transport with minor limb trauma. The diversion pathway triage process appropriately identified 182 patients ineligible for diversion. 96.7% of patients reported satisfaction with care received from the diversion pathway. There was no change in ED representation rates for diverted patients. CONCLUSIONS: A new pathway resulted in reduced LOS, reduced DNW, high patient satisfaction and more people being discharged within 4 h for diverted patients compared to usual ED care. The pathway increased ED capacity, improved key ED performance metrics and safely expedited care delivery for patients.

'I thought they would do it on the spot': why do people with non-traumatic musculoskeletal pain present to emergency departments?

Objective To investigate the reasons patients with non-traumatic musculoskeletal pain (NTMSP) present to an emergency department (ED), their experience of care and perceptions about managing their condition in the future. Methods A qualitative study using semi-structured interviews with patients with NTMSP presenting to a suburban ED. A purposive sampling strategy included participants with different pain characteristics, demographics and psychological factors. Results Eleven patients with NTMSP who presented to an ED were interviewed, reaching saturation of major themes. Seven reasons for ED presentation were identified: (1) desire for pain relief, (2) inability to access other healthcare, (3) expecting comprehensive care at the ED, (4) fear of serious pathology/outcome, (5) influence of a third party, (6) desire/expecting radiological imaging for diagnosis and (7) desire for 'ED specific' interventions. Participants were influenced by a unique combination of these reasons. Some expectations were underpinned by misconceptions about health services and care. While most participants were satisfied with their ED care, they would prefer to self-manage and seek care elsewhere in the future. Conclusions The reasons for ED presentation in patients with NTMSP are varied and often influenced by misconceptions about ED care. Most participants reported that, in future, they were satisfied to access care elsewhere. Clinicians should assess patient expectations so misconceptions about ED care can be addressed.

Evaluation of Provider Assessment of Clinical History When Using the HEART Score.

Objective: The HEART Score is a clinically validated risk stratification tool for patients with chest pain. Using five parameters (History, Electrocardiogram, Age, Risk factors, and Troponin), this instrument categorizes patients as low, moderate, or high risk for major adverse cardiac events within six weeks after evaluation. Of these parameters, History is the most subjective, as providers independently assign their level of clinical suspicion. Overestimation of history, and ultimately the HEART Score, can result in increased resource utilization, expense, and patient risk. We sought to evaluate bias in provider assessment of history when determining the HEART Score. Methods: Emergency medicine (EM) and Cardiology providers received surveys with one of two versions of clinical vignettes randomized at the question level and were asked to estimate the history component of the HEART Score. Vignettes differed by age, risk factors, sex, and socioeconomic status (SES), but both versions should have received the same score for history. Statistical analysis was then used to assess differences in history assessment between vignettes. Results: Of the 884 responses analyzed, most providers overestimated the historical portion of the HEART Score when assessing risk factors, patient distress, age, and lower SES. Many underestimated history with knowledge of a previous negative stress test. When controlling for specialty, the universal theme was overestimation by EM providers and underestimation by cardiologists. Despite the presence of hypertension, gender differences, and the appearance of mild distress, cardiologists were more likely to correctly estimate history compared to EM providers. SES consideration generally led to an underestimation of history by cardiologists. These findings were all statistically significant. Conclusion: Our study demonstrates that both EM and cardiology providers overestimate history when considering prognosticators that are frequently viewed as concerning. Further education on proper usage of the HEART Score is needed for more appropriate scoring of history and improved resource allocation for hospital systems.

Association between pelvic pain bothersomeness and pain sensitivity: A community-based cross-sectional study of young adult females in the Raine Study.

OBJECTIVE: Pelvic pain has been associated with augmented nociceptive processing, but large studies controlling for multiple potential confounding factors are lacking. This study investigated the association between pelvic pain bothersomeness and pain sensitivity in young adult women, accounting for potential confounding factors. DESIGN: Cross-sectional study. SETTING: Community-dwelling sample. POPULATION: The Raine Study Gen2-22 year follow-up (n = 475). MAIN OUTCOME MEASURES: The experience of bothersomeness related to pelvic pain was determined from a question in the Urogenital Distress Inventory short form. Pain sensitivity was measured using pressure pain and cold pain thresholds. Potential confounding factors included ethnicity, marital status, highest level of education, income, waist-hip ratio, level of activity, sleep quality, smoking, comorbidity history, C-reactive protein level, musculoskeletal pain experience and psychological distress. RESULTS: Three hundred and sixty-two women (76.2%) reported no pelvic pain bothersomeness, 74 (15.6%) reported mild pelvic pain bothersomeness and 39 (8.2%) reported moderate-severe pelvic pain bothersomeness. After adjusting for marital status (and test site), moderate-severe pelvic pain bothersomeness was associated with a lower pressure pain threshold (i.e. greater pressure pain sensitivity) (coefficient -51.46, 95% CI -98.06 to -4.86, p = 0.030). After adjusting for smoking, moderate-severe pelvic pain bothersomeness was also associated with a higher cold pain threshold (i.e. greater cold pain sensitivity) (coefficient 4.35, 95% CI 0.90-7.79, p = 0.014). CONCLUSIONS: This study suggests augmented nociceptive processing as a contributing factor in pelvic pain bothersomeness for some women. Thorough assessment of women who present clinically with pelvic pain should consider pain sensitivity as a potential contributing factor to their presentation.

The Scribe Effect: the Impact of a Pre-matriculation Experience on Subsequent Medical School Education.

Medical scribes have been utilized since the 1970s but have been in ever-increasing demand over the past 25 years. The reasons for this growth have been well documented, with positive impacts on provider well-being, patient satisfaction, clinical efficiency, and revenue generation. Many aspiring healthcare providers become medical scribes during or immediately after college, believing it will provide them with helpful experience and increase their chances of gaining entrance into medical education. However, little data exists to justify those beliefs. Through written surveys and semi-structured interviews, we found that scribes feel that their experience shaped their futures in medicine in two broad themes, specifically confirming their commitment to medicine (with subthemes of specialty choice, establishing mentorship, and exposure to difficult topics) and the essential skills of a physician (with subthemes of communication, professionalism, history and physical, terminology and jargon, and clinical reasoning). Understanding the impact of a scribe experience may provide medical school admissions personnel a more thorough sense of the scribe's strengths and likelihood of success in training, and should generate testable hypotheses for further studies into the learning processes of medical scribes.

The association of early life stressors with pain sensitivity and pain experience at 22 years.

Early life stress (ELS) can significantly influence biological pathways associated with nociception, increasing vulnerability to future heightened pain sensitivity and subsequent risk of pain events. However, very little human research has investigated the association of ELS, measured across multiple domains, with future pain sensitivity. Data from Gen1 and Gen2 of the Raine Study were used to assess the association between a wide range of early life stressors, including antenatally, and pressure and cold pain sensitivity at young adulthood. Participants were classified into 2 groups according to their cold pain sensitivity. In addition, the interaction between ELS, pain sensitivity, and pain experience (based on Örebro Musculoskeletal Pain Questionnaire) at age 22 years was examined. Analysis was performed using both a complete case and multiple imputation approach, adjusting for contemporaneous 22-year correlates, with comparable results in each model. More problematic behaviour at age 2 years was associated with less pressure pain sensitivity at 22 years (13.7 kPa, 95% CI: 1.0-27.0, P = 0.037), with no interaction between problematic behaviour and pain experience at 22 years. For those reporting a moderate/high pain experience at 22 years, poor family functioning increased the odds ratio for high cold pain sensitivity (3.0, 95% CI: 1.6-5.6), but for those reporting no/low pain experience, it did not (OR:1.2, 95% CI: 0.8-1.8). This study provides the most comprehensive investigation of the relationship between ELS and pressure and cold pain sensitivity in young adults supporting early life as a critical period of development influencing future nociceptive processing.

Associations of physical activity or sedentary behaviour with pain sensitivity in young adults of the Raine Study.

BACKGROUND AND AIMS: There is high level evidence for physical activity (PA) improving outcomes in persistent pain disorders and one of the mechanisms proposed is the effect of exercise on central nociceptive modulation. Although laboratory studies and small field intervention studies suggest associations between physical activity and pain sensitivity, the association of objectively measured, habitual PA and sedentary behaviour (SB) with pain sensitivity requires further investigation. Current evidence suggests PA typically lowers pain sensitivity in people without pain or with single-site pain, whereas PA is frequently associated with an increase in pain sensitivity for those with multisite pain. The aim of this study was to explore the relationships of PA and SB with pain sensitivity measured by pressure pain thresholds and cold pain thresholds, considering the presence of single-site and multisite pain and controlling for potential confounders. METHODS: Participants from the Western Australian Pregnancy Cohort (Raine) Study (n = 714) provided data at age 22-years. PA and SB were measured via accelerometry over a 7-day period. Pain sensitivity was measured using pressure pain threshold (4 sites) and cold pain threshold (wrist). Participants were grouped by number of pain areas into "No pain areas" (n = 438), "Single-site pain" (n = 113) and "Multisite pain" (n = 163) groups. The association of PA and SB variables with pain sensitivity was tested separately within each pain group by multivariable regression, adjusting for potential confounders. RESULTS: For those with "Single-site pain", higher levels (>13 min/day) of moderate-vigorous PA in ≥10 min bouts was associated with more pressure pain sensitivity (p = 0.035). Those with "Multisite pain" displayed increased cold pain sensitivity with greater amounts of vigorous PA (p = 0.011). Those with "No pain areas" displayed increased cold pain sensitivity with decreasing breaks from sedentary time (p = 0.046). CONCLUSIONS: This study was a comprehensive investigation of a community-based sample of young adults with "No pain areas", "Single-site pain" and "Multisite pain" and suggests some associations of measures of PA and SB with pain sensitivity. IMPLICATIONS: The findings suggest that the pattern of accumulation of PA and SB may be important to inform improved clinical management of musculoskeletal pain disorders. This study provides a baseline for follow-up studies using the Raine Study cohort. Future research should consider temporal influences of PA and SB on pain sensitivity, pain experience and consider using a broader range of pain sensitivity measures.

Non-traumatic musculoskeletal pain in Western Australian hospital emergency departments: A clinical audit of the prevalence, management practices and evidence-to-practice gaps.

OBJECTIVES: Musculoskeletal pain (MSP) conditions are a leading cause of morbidity worldwide and a common reason for ED presentation. Little is currently known about non-traumatic MSP (NTMSP) presenting to EDs. The present study described the prevalence and management practices of NTMSP in EDs. METHODS: The design was a retrospective clinical audit in two hospital EDs in Western Australia covering 3 months beginning 1 January 2016. We defined NTMSP as pain of musculoskeletal origin occurring in the absence of external force or excessive physical loading. The outcomes measured included: patient, condition and hospital-episode characteristics, as well as management practices. Management practices were compared to recommended care derived from guideline recommendations. These included: assessment for red flags and psychosocial risk factors, appropriate use of diagnostic imaging, provision of patient education, administration and prescription of analgesic medication, and assessment of risk factors for opioid-related harm. RESULTS: Eight hundred and eighty-eight patients were included in the present study. NTMSP accounted for 3.0% of all ED presentations. According to clinician documentation, red flag and psychosocial assessments were recorded in 73.3 and 10.5% of patients. Forty-one percent of patients were referred for imaging, of which 39.7% were inconsistent with guideline recommendations. Education was recorded 52.0% of the time. At least one opioid medication was administered to 55.3% of patients and there was no documented assessment of risk factors for opioid-related harm. CONCLUSIONS: NTMSP is a relatively common reason for ED presentation. Documented management practices are discordant with guideline recommendations. Strategies to improve the concordance between management and guideline recommendations are needed.

Associations Between Musculoskeletal Pain Experience and Pressure and Cold Pain Sensitivity: A Community-based Cross-sectional Study of Young Adults in the Raine Study.

OBJECTIVES: To investigate the cross-sectional associations between musculoskeletal pain experience and measures of pressure and cold pain sensitivity in young adults from the Western Australian Pregnancy Cohort (Raine) Study. PARTICIPANTS AND METHODS: In total, 917 participants were eligible for analysis if they provided data pertaining to musculoskeletal pain status at the 22-year follow-up and had data for at least 1 valid pain sensitivity test. Standardized protocols were used to assess pressure pain threshold (4 sites: lumbar spine, tibialis anterior, upper trapezius, and wrist) and cold pain threshold (wrist). Four pain experience groups ("No pain" [n=562, 61.3%], "Low" [n=84, 9.2%], "Medium" [n=147, 16.0%], "High" [n=124, 13.5%]) were determined by latent class analysis using parameters of pain chronicity, frequency, intensity, and number of pain areas. Variables considered as confounders included sex, age, ethnicity, waist-hip ratio, psychological symptoms, sleep quality, physical activity, sedentary behavior, smoking, and income. RESULTS: There were no associations between pain experience and pressure pain sensitivity after adjusting for confounders. The "Medium" and "High" pain experience groups demonstrated heightened cold pain sensitivity compared with the "No pain" group (P=0.023), adjusted for sex and smoking. DISCUSSION: This study provides the most extensive investigation of the relationship between musculoskeletal pain experience and pressure and cold pain sensitivity in young adults. Heightened cold pain sensitivity in those classified as "Medium" and "High" pain experience may suggest altered nociceptive processing and has implications for clinical management.

Are measures of pain sensitivity associated with pain and disability at 12-month follow up in chronic neck pain?

OBJECTIVES: Pain sensitivity and psychosocial issues are prognostic of poor outcome in acute neck disorders. However, knowledge of associations between pain sensitivity and ongoing pain and disability in chronic neck pain are lacking. We aimed to investigate associations of pain sensitivity with pain and disability at the 12-month follow-up in people with chronic neck pain. METHODS: The predictor variables were: clinical and quantitative sensory testing (cold, pressure); neural tissue sensitivity; neuropathic symptoms; comorbidities; sleep; psychological distress; pain catastrophizing; pain intensity (for the model explaining disability at 12 months only); and disability (for the model explaining pain at 12 months only). Data were analysed using uni- and multivariate regression models to assess associations with pain and disability at the 12-month follow-up (n = 64 at baseline, n = 51 at follow-up). RESULTS: Univariable associations between all predictor variables and pain and disability were evident (r > 0.3; p < 0.05), except for cold and pressure pain thresholds and cold sensitivity. For disability at the 12-month follow-up, 24.0% of the variance was explained by psychological distress and comorbidities. For pain at 12 months, 39.8% of the variance was explained primarily by baseline disability. CONCLUSIONS: Neither clinical nor quantitative measures of pain sensitivity were meaningfully associated with long-term patient-reported outcomes in people with chronic neck pain, limiting their clinical application in evaluating prognosis.

Poor overall quality of clinical practice guidelines for musculoskeletal pain: a systematic review.

OBJECTIVES: Undertake a systematic critical appraisal of contemporary clinical practice guidelines (CPGs) for common musculoskeletal (MSK) pain conditions: spinal (lumbar, thoracic and cervical), hip/knee (including osteoarthritis) and shoulder. DESIGN: Systematic review of CPGs (PROSPERO number: CRD42016051653).Included CPGs were written in English, developed within the last 5 years, focused on adults and described development processes. Excluded CPGs were for: traumatic MSK pain, single modalities (eg, surgery), traditional healing/medicine, specific disease processes (eg, inflammatory arthropathies) or those that required payment. DATA SOURCES AND METHOD OF APPRAISAL: Four scientific databases (MEDLINE, Embase, CINAHL and Physiotherapy Evidence Database) and four guideline repositories. The Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument was used for critical appraisal. RESULTS: 4664 records were identified, and 34 CPGs were included. Most were for osteoarthritis (n=12) or low back pain (n=11), most commonly from the USA (n=12). The mean overall AGREE II score was 45% (SD=19.7). Lowest mean domain scores were for applicability (26%, SD=19.5) and editorial independence (33%, SD=27.5). The highest score was for scope and purpose (72%, SD=14.3). Only 8 of 34 CPGS were high quality: for osteoarthritis (n=4), low back pain (n=2), neck (n=1) and shoulder pain (n=1).

Characteristics of NPS use in patients admitted to acute psychiatric services in Southeast Scotland: a retrospective cross-sectional analysis following public health interventions.

OBJECTIVES: Assess the impact of selective prohibition and seizure of novel psychoactive substances (NPS) supply on NPS use prevalence within psychiatric admissions and evaluate demographic characteristics of current NPS users. DESIGN: A 6-month retrospective cross-sectional analysis of discharge letters between 1 October 2015 and 31 March 2016. SETTING: General psychiatry inpatients and intensive home treatment team (IHTT) community patients at a psychiatric hospital in a Scottish city. PARTICIPANTS: All participants were between the ages of 18 and 65 years. After application of exclusion criteria, 473 discharge letters of general psychiatry patients were deemed suitable for analysis and 264 IHTT patient discharge letters were analysed. INTERVENTIONS: A nationwide temporary class drug order (TCDO) was placed on 10 April 2015 reclassifying methylphenidate-related compounds as class B substances. On 15 October 2015, local forfeiture orders were granted to trading standards permitting the seizure of NPS supplies. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was to determine the prevalence of NPS use in two cohorts. Second, demographic features of patients and details regarding their psychiatric presentation were analysed. RESULTS: The prevalence of NPS use in general psychiatry and IHTT patients was 6.6% and 3.4%, respectively. Inpatients using NPS compared with non-users were more likely to be men (OR 2.92, 95% CI 1.28 to 6.66, P=0.009), have a forensic history (OR 5.03, CI 2.39 to 10.59, P<0.001) and be detained under an Emergency Detention Certificate (OR 3.50, CI 1.56 to 7.82, P=0.004). NPS users were also more likely to be diagnosed under International Statistical Classification of Diseases and Related Health Problems, Version 10, F10-19 (OR 9.97, CI 4.62 to 21.49, P<0.001). CONCLUSIONS: Compared with previous work, psychiatric inpatient NPS use has fallen. NPS continue to be used by a demographic previously described resulting in presentations consistent with a drug-induced psychosis and at times requiring detention under the Mental Health Act. Further research is required to evaluate the effectiveness of the recent prohibition of all NPS.

Pressure and cold pain threshold reference values in a large, young adult, pain-free population.

BACKGROUND AND AIMS: Currently there is a lack of large population studies that have investigated pain sensitivity distributions in healthy pain free people. The aims of this study were: (1) to provide sex-specific reference values of pressure and cold pain thresholds in young pain-free adults; (2) to examine the association of potential correlates of pain sensitivity with pain threshold values. METHODS: This study investigated sex specific pressure and cold pain threshold estimates for young pain free adults aged 21-24 years. A cross-sectional design was utilised using participants (n=617) from the Western Australian Pregnancy Cohort (Raine) Study at the 22-year follow-up. The association of site, sex, height, weight, smoking, health related quality of life, psychological measures and activity with pain threshold values was examined. Pressure pain threshold (lumbar spine, tibialis anterior, neck and dorsal wrist) and cold pain threshold (dorsal wrist) were assessed using standardised quantitative sensory testing protocols. RESULTS: Reference values for pressure pain threshold (four body sites) stratified by sex and site, and cold pain threshold (dorsal wrist) stratified by sex are provided. Statistically significant, independent correlates of increased pressure pain sensitivity measures were site (neck, dorsal wrist), sex (female), higher waist-hip ratio and poorer mental health. Statistically significant, independent correlates of increased cold pain sensitivity measures were, sex (female), poorer mental health and smoking. CONCLUSIONS: These data provide the most comprehensive and robust sex specific reference values for pressure pain threshold specific to four body sites and cold pain threshold at the dorsal wrist for young adults aged 21-24 years. Establishing normative values in this young age group is important given that the transition from adolescence to adulthood is a critical temporal period during which trajectories for persistent pain can be established. IMPLICATIONS: These data will provide an important research resource to enable more accurate profiling and interpretation of pain sensitivity in clinical pain disorders in young adults. The robust and comprehensive data can assist interpretation of future clinical pain studies and provide further insight into the complex associations of pain sensitivity that can be used in future research.

Clinical Ratings of Pain Sensitivity Correlate With Quantitative Measures in People With Chronic Neck Pain and Healthy Controls: Cross-Sectional Study.

BACKGROUND: Correlations between clinical and quantitative measures of pain sensitivity are poor, making it difficult for clinicians to detect people with pain sensitivity. Clinical detection of pain sensitivity is important because these people have a different prognosis and may require different treatment. OBJECTIVE: The purpose of this study was to investigate the relationship between clinical and quantitative measures of pain sensitivity across individuals with and without neck pain. METHODS: This cross-sectional study included 40 participants with chronic neck pain and 40 age- and sex-matched controls. Participants underwent quantitative sensory testing of cold pain thresholds (CPTs) and pressure pain thresholds (PPTs). Clinical tests for pain sensitivity were the ice pain test and the pressure pain test. All tests were undertaken at standardized local (neck and upper trapezius muscles) and remote (wrist and tibialis anterior muscles) sites. Median and interquartile range (IQR) were calculated for neck pain and control groups, and parametric and nonparametric tests were used to compare groups. Correlation coefficients were calculated between quantitative and clinical measures. RESULTS: There were significant differences for clinical and quantitative measures of cold and pressure sensitivity between the neck pain and control groups (eg, CPT neck pain group: median=22.31°C, IQR=18.58°C; control group: median=5.0°C, IQR=0.74°C). Moderate-to-good correlations were found between the clinical ice pain test and CPT at all sites (.46 to .68) except at the wrist (.29 to .40). Fair correlations were found for the clinical pressure pain test and PPT (-.26 to -.45). Psychological variables contributing to quantitative measures of pain sensitivity included catastrophization, sleep quality, and female sex. LIMITATIONS: Clinical pressure pain tests were not quantitatively standardized in this study. CONCLUSIONS: The ice pain test may be useful as a clinical correlate of CPT at all sites except the wrist, whereas the pressure pain test is less convincing as a clinical correlate of PPT.

Reliability of pressure pain threshold testing in healthy pain free young adults.

Background and aims Investigation of the multidimensional correlates of pressure pain threshold (PPT) requires the study of large cohorts, and thus the use of multiple raters, for sufficient statistical power. Although PPT testing has previously been shown to be reliable, the reliability of multiple raters and investigation for systematic bias between raters has not been reported. The aim of this study was to evaluate the intrarater and interrater reliability of PPT measurement by handheld algometer at the wrist, leg, cervical spine and lumbar spine. Additionally the study aimed to calculate sample sizes required for parallel and cross-over studies for various effect sizes accounting for measurement error. Methods Five research assistants (RAs) each tested 20 pain free subjects at the wrist, leg, cervical and lumbar spine. Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and systematic bias were calculated. Results Both intrarater reliability (ICC = 0.81-0.99) and interrater reliability (ICC = 0.92-0.95) were excellent and intrarater SEM ranged from 79 to 100 kPa. There was systematic bias detected at three sites with no single rater tending to consistently rate higher or lower than others across all sites. Conclusion The excellent ICCs observed in this study support the utility of using multiple RAs in large cohort studies using standardised protocols, with the caveat that an absence of any confounding of study estimates by rater is checked, due to systematic rater bias identified in this study. Implications Thorough training of raters using PPT results in excellent interrater reliability. Clinical trials using PPT as an outcome measure should utilise a priori sample size calculations.