A Psychophysical Investigation of the Facial Action Coding System as an Index of Pain Variability among Older Adults with and without Alzheimer's Disease

Factors influencing nurses' pain assessment and management of road traffic casualties: a qualitative study at a military hospital in Ghana

BACKGROUND

Evidence shows that patients who visit the surgical and trauma emergency units may be discharged with untreated or increased pain levels. This study explored nurses' pain assessment and management approaches at a trauma-surgical emergency unit in Ghana.

METHODS

Seventeen nurses who work in the trauma department participated in this qualitative exploratory descriptive study. In-depth individual interviews were conducted, and the thematic analysis was utilized to identify emerging themes and subthemes.

RESULTS

Three main themes were identified: patient pain indicators, pain management, and institutional factors influencing pain management. The study revealed that nurses rely on verbal expressions, non-verbal cues, physiological changes, and the severity of pain communicated. The findings highlighted staff shortage, inadequate resources, and lack of standardized guidelines as factors affecting pain and management.

CONCLUSIONS

Although the study offers critical new perspectives on nurses' experiences regarding pain related issues at the trauma-surgical emergency units, its small sample size limited its generalizability.

Increased pain unpleasantness and pain-related fMRI activation in the periaqueductal gray in Alzheimer's disease

Background

Pain continues to be underrecognized and undertreated in people with Alzheimer's disease (AD). The periaqueductal gray (PAG) is essential to pain processing and modulation yet is damaged by AD. While evidence exists of altered neural processing of pain in AD, there has not been a focused investigation of the PAG during pain in people with AD.

Purpose

To investigate the role of the PAG in sensory and affective pain processing for people living with AD.

Methods

Participants from a larger study completed pain psychophysics assessments and then a perceptually-matched heat pain task (warmth, mild, and moderate pain) during a functional MRI scan. In this cross-sectional study, we examined blood oxygenation level-dependent (BOLD) responses in the PAG and other pain-related regions in participants with AD (n = 18) and cognitively intact older adults (age- and sex-matched, n = 18). Associations of BOLD percent signal change and psychophysics were also examined.

Results

There were significant main effects of AD status on the temperature needed to reach each perception of warmth or pain, where people with AD reached higher temperatures. Furthermore, participants with AD rated mild and moderate pain as more unpleasant than controls. PAG BOLD activation was greater in AD relative to controls during warmth and mild pain percepts. No significant differences were found for moderate pain or in other regions of interest. Greater PAG activation during mild pain was associated with higher affective/unpleasantness ratings of mild pain in participants with AD but not in controls.

Conclusion

Results suggest a role for the PAG in altered pain responses in people with AD. The PAG is the primary source of endogenous opioid pain inhibition in the neuroaxis, thus, altered PAG function in AD suggests possible changes in descending pain inhibitory circuits. People with AD may have a greater risk of suffering from pain compared to cognitively intact older adults.

The influence of Alzheimer's disease stigma on pain assessment in older persons

INTRODUCTION

Pain of nursing homes residents with Alzheimer's disease remains under detected compared to their cognitively intact counterparts. Communication difficulties may partly explain this poor quality of care but the influence of stigmatization on pain assessment has never been explored.

RESEARCH QUESTION

The objective of this research was to analyze whether a diagnosis label of Alzheimer's disease or the stage of the disease may bias pain assessment scores and empathic reactions of health care staff in nursing homes.

METHODS

Two studies were conducted based on a similar experimental between-subjects design with a video showing an older adult woman experiencing undefined pain. Different labels and vignettes were manipulated to characterize the subject of the video. In the first study, 84 certified nursing assistants were asked to watch the video and then to assess the pain intensity and their empathic reaction. Participants were randomized in two conditions that varied the disease label (Alzheimer's disease vs no diagnosis). In the second study, 67 certified nursing assistants were enrolled who did not participate in the first study. They watched the same video as in the first study and assessed the pain intensity and their empathic reaction. They were randomized in two conditions that varied the stage of the Alzheimer's disease (mild stage vs severe stage).

RESULTS

Alzheimer's disease label had no influence on assessment scores. In contrast, the stage of the disease had a significant effect on the health care staff assessments with severe stage associated with lower pain intensity scores and empathic reactions.

CONCLUSION

These results confirm that the Alzheimer's disease stigma is a real phenomenon that tends to be mainly elicited by the symptoms of the acute phase of the disease. These findings are crucial to better understand the stigma related to Alzheimer's disease and to enhance the pain management of this frail population.

Multimodal explainable AI predicts upcoming speech behavior in adults who stutter

A key goal of cognitive neuroscience is to better understand how dynamic brain activity relates to behavior. Such dynamics, in terms of spatial and temporal patterns of brain activity, are directly measured with neurophysiological methods such as EEG, but can also be indirectly expressed by the body. Autonomic nervous system activity is the best-known example, but, muscles in the eyes and face can also index brain activity. Mostly parallel lines of artificial intelligence research show that EEG and facial muscles both encode information about emotion, pain, attention, and social interactions, among other topics. In this study, we examined adults who stutter (AWS) to understand the relations between dynamic brain and facial muscle activity and predictions about future behavior (fluent or stuttered speech). AWS can provide insight into brain-behavior dynamics because they naturally fluctuate between episodes of fluent and stuttered speech behavior. We focused on the period when speech preparation occurs, and used EEG and facial muscle activity measured from video to predict whether the upcoming speech would be fluent or stuttered. An explainable self-supervised multimodal architecture learned the temporal dynamics of both EEG and facial muscle movements during speech preparation in AWS, and predicted fluent or stuttered speech at 80.8% accuracy (chance=50%). Specific EEG and facial muscle signals distinguished fluent and stuttered trials, and systematically varied from early to late speech preparation time periods. The self-supervised architecture successfully identified multimodal activity that predicted upcoming behavior on a trial-by-trial basis. This approach could be applied to understanding the neural mechanisms driving variable behavior and symptoms in a wide range of neurological and psychiatric disorders. The combination of direct measures of neural activity and simple video data may be applied to developing technologies that estimate brain state from subtle bodily signals.

Faces of Pain in Dementia: Learnings From a Real-World Study Using a Technology-Enabled Pain Assessment Tool

Pain is common in people living with dementia (PLWD), including those with limited verbal skills. Facial expressions are key behavioral indicators of the pain experience in this group. However, there is a lack of real-world studies to report the prevalence and associations of pain-relevant facial micro-expressions in PLWD. In this observational retrospective study, pain-related facial features were studied in a sample of 3,144 PLWD [mean age 83.3 years (SD = 9.0); 59.0% female] using the Face domain of PainChek®, a point-of-care medical device application. Pain assessments were completed by 389 users from two national dementia-specific care programs and 34 Australian aged care homes. Our analysis focused on the frequency, distribution, and associations of facial action units [AU(s)] with respect to various pain intensity groups. A total of 22,194 pain assessments were completed. Of the AUs present, AU7 (eyelid tightening) was the most frequent facial expression (48.6%) detected, followed by AU43 (closing eyes; 42.9%) and AU6 (cheek raising; 42.1%) during severe pain. AU20 (horizontal mouth stretch) was the most predictive facial action of higher pain scores. Eye-related AUs (AU6, AU7, AU43) and brow-related AUs (AU4) were more common than mouth-related AUs (e.g., AU20, AU25) during higher pain intensities. No significant effect was found for age or gender. These findings offer further understanding of facial expressions during clinical pain in PLWD and confirm the usefulness of artificial intelligence (AI)-enabled real-time analysis of the face as part of the assessment of pain in aged care clinical practice.

Mental states and personality based on real-time physical activity and facial expression recognition

INTRODUCTION

To explore a quick and non-invasive way to measure individual psychological states, this study developed interview-based scales, and multi-modal information was collected from 172 participants.

METHODS

We developed the Interview Psychological Symptom Inventory (IPSI) which eventually retained 53 items with nine main factors. All of them performed well in terms of reliability and validity. We used optimized convolutional neural networks and original detection algorithms for the recognition of individual facial expressions and physical activity based on Russell's circumplex model and the five factor model.

RESULTS

We found that there was a significant correlation between the developed scale and the participants' scores on each factor in the Symptom Checklist-90 (SCL-90) and Big Five Inventory (BFI-2) [r = (-0.257, 0.632), p < 0.01]. Among the multi-modal data, the arousal of facial expressions was significantly correlated with the interval of validity (p < 0.01), valence was significantly correlated with IPSI and SCL-90, and physical activity was significantly correlated with gender, age, and factors of the scales.

DISCUSSION

Our research demonstrates that mental health can be monitored and assessed remotely by collecting and analyzing multimodal data from individuals captured by digital tools.

Pain-related health care costs for long-term care residents

Background

We tested for differences in direct health care costs among long-term care (LTC) residents age 65 and older with clinically significant pain (CSP) and with no pain or non-daily mild pain (NP/NDMP). We are not aware of any other large scale investigation that examined the cost of pain in LTC environments.

Methods

Population-based administrative health data from Saskatchewan, Canada for 2004 to 2015 were used to compare direct health care costs for CSP and NP/NDMP groups up to one year after admission to LTC. Total accumulated costs for hospitalization, physician services, LTC, and prescription drugs were calculated in 2015 Canadian dollars. Group differences were tested using generalized linear models with generalized estimating equations.

Results

Amongst 24,870 LTC residents, 8289 (33.3%) were censored due to death or discharge in the 365-day study observation period. Of the 16,581 (66.7%) observed residents, 5683 (34.3%) had CSP at admission. Residents (66.3% female) had a mean age of 85 years (SD = 7.4). The mean annual total direct health care cost per resident was higher among the CSP group (CAD $8063) than the NP/NDMP group (CAD $6455). This difference was found even after including LTC costs, and for each cost component (i.e., CSP residents had higher hospitalization, physician, and prescription drug costs). Similar results were obtained after controlling for demographics, comorbidities, physical and cognitive impairment, prior health care costs, and facility characteristics.

Conclusion

The higher costs incurred by CSP residents compared to NP/NDMP residents are likely underestimated because pain problems are often missed in residents with dementia, who comprise a large portion of the LTC population. Improved pain care can reduce such costs and improve quality of life.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02424-2.

The Effectiveness of Facial Expression Recognition in Detecting Emotional Responses to Sound Interventions in Older Adults With Dementia

This research uses facial expression recognition software (FaceReader) to explore the influence of different sound interventions on the emotions of older people with dementia. The field experiment was carried out in the public activity space of an older adult care facility. Three intervention sound sources were used, namely, music, stream, and birdsong. Data collected through the Self-Assessment Manikin Scale (SAM) were compared with facial expression recognition (FER) data. FaceReader identified differences in the emotional responses of older people with dementia to different sound interventions and revealed changes in facial expressions over time. The facial expression of the participants had significantly higher valence for all three sound interventions than in the intervention without sound (p < 0.01). The indices of sadness, fear, and disgust differed significantly between the different sound interventions. For example, before the start of the birdsong intervention, the disgust index initially increased by 0.06 from 0 s to about 20 s, followed by a linear downward trend, with an average reduction of 0.03 per 20 s. In addition, valence and arousal were significantly lower when the sound intervention began before, rather than concurrently with, the start of the activity (p < 0.01). Moreover, in the birdsong and stream interventions, there were significant differences between intervention days (p < 0.05 or p < 0.01). Furthermore, facial expression valence significantly differed by age and gender. Finally, a comparison of the SAM and FER results showed that, in the music intervention, the valence in the first 80 s helps to predict dominance (r = 0.600) and acoustic comfort (r = 0.545); in the stream sound intervention, the first 40 s helps to predict pleasure (r = 0.770) and acoustic comfort (r = 0.766); for the birdsong intervention, the first 20 s helps to predict dominance (r = 0.824) and arousal (r = 0.891).

Pain processing in older adults with dementia-related cognitive impairment is associated with frontal neurodegeneration

Experimental pain research has shown that pain processing seems to be heightened in dementia. It is unclear which neuropathological changes underlie these alterations. This study examined whether differences in pressure pain sensitivity and endogenous pain inhibition (conditioned pain modulation (CPM)) between individuals with a dementia-related cognitive impairment (N=23) and healthy controls (N=35) are linked to dementia-related neurodegeneration. Pain was assessed via self-report ratings and by analyzing the facial expression of pain using the Facial Action Coding System. We found that cognitively impaired individuals show decreased CPM inhibition as assessed by facial responses compared to healthy controls, which was mediated by decreased gray matter volume in the medial orbitofrontal and anterior cingulate cortex in the patient group. This study confirms previous findings of intensified pain processing in dementia when pain is assessed using non-verbal responses. Our findings suggest that a loss of pain inhibitory functioning caused by structural changes in prefrontal areas might be one of the underlying mechanisms responsible for amplified pain responses in individuals with a dementia-related cognitive impairment.

Experimentally evoked pain in Alzheimer's disease

BACKGROUND

Pain continues to be underrecognized and undertreated in Alzheimer's disease (AD) while existing guidance about pain assessment and management in dementia is not widespread. Brain regions involved in pain processing and modulation are damaged during AD, and the pain experience in AD is not well understood. Experimental pain studies using psychophysics can further our understanding of the pain experience in AD, which may lead to improved assessment and management of pain in people living with AD.

OBJECTIVE

A systematic review was conducted to explicate the current understanding of experimentally evoked pain in AD from primary research using psychophysical methods.

DATA SOURCES

Peer-reviewed publications were found via PubMed, CINAHL, and PsycINFO. A total of 18 primary research, peer-reviewed full articles that met inclusion criteria were included, representing 929 total participants.

CONCLUSIONS

Experimentally evoked pain in people with AD demonstrates that despite cognitive impairment and a reduced ability to effectively communicate, individuals with AD experience pain similar to or more unpleasant than cognitively intact older adults. This may mean amplified pain unpleasantness in people with AD.

IMPLICATIONS FOR PRACTICE

Our current best practices need to be widely disseminated and put into clinical practice. Self-report of pain continues to be the gold standard, but it is ineffective for noncommunicative patients and those unable to understand pain scales or instructions because of memory/cognitive impairment. Instead, pain treatment should be ethically initiated based on patient reports and behaviors, caregiver/surrogate reports, review of the medical record for painful conditions, analgesic trials, and regular reassessments.

An Eye Tracking Investigation of Pain Decoding Based on Older and Younger Adults' Facial Expressions

Nonverbal pain cues such as facial expressions, are useful in the systematic assessment of pain in people with dementia who have severe limitations in their ability to communicate. Nonetheless, the extent to which observers rely on specific pain-related facial responses (e.g., eye movements, frowning) when judging pain remains unclear. Observers viewed three types of videos of patients expressing pain (younger patients, older patients without dementia, older patients with dementia) while wearing an eye tracker device that recorded their viewing behaviors. They provided pain ratings for each patient in the videos. These observers assigned higher pain ratings to older adults compared to younger adults and the highest pain ratings to patients with dementia. Pain ratings assigned to younger adults showed greater correspondence to objectively coded facial reactions compared to older adults. The correspondence of observer ratings was not affected by the cognitive status of target patients as there were no differences between the ratings assigned to older adults with and without dementia. Observers' percentage of total dwell time (amount of time that an observer glances or fixates within a defined visual area of interest) across specific facial areas did not predict the correspondence of observers' pain ratings to objective coding of facial responses. Our results demonstrate that patient characteristics such as age and cognitive status impact the pain decoding process by observers when viewing facial expressions of pain in others.

Interrater Variability in Pain Assessment of Long-term Care Residents with Dementia

PURPOSE

People with dementia are at great risk of their pain being undetected. In long-term care facilities, certified nursing assistants are on the front-line to detect whether a resident with dementia is experiencing pain, but research on certified nursing assistants' abilities to accurately assess pain are scarce. This study aims to examine certified nursing assistants' pain assessment skills using a simulated standardized video context.

DESIGN

A cross-sectional study was conducted.

METHODS

Fifty certified nursing assistants and 40 individuals with no professional experience in the field of care (controls) watched the same video of an older adult woman with dementia experiencing pain. Afterwards, they completed visual analog scales (pain intensity, affective distress), an observational pain assessment scale (Algoplus), and a set of questionnaires.

RESULTS

In both groups, pain intensity assessment and empathic reaction scores showed important interrater variability. Moreover, certified nursing assistants and controls did not differ in detecting the presence of pain or assessing its intensity. But certified nursing assistants displayed lower empathic reactions and dispositions. Certified nursing assistants pain assessment scores decreased with experience and expertise.

CONCLUSIONS

The practice of pain assessment is challenging for certified nursing assistants in long-term care facilities. Their professional status does not prevent inter-personal inconsistency and tends to lower their empathic dispositions. Personal determinants may interfere with their assessment behaviors and must be considered to enhance pain management for residents with dementia.

Resting-State Magnetoencephalography Reveals Neurobiological Bridges Between Pain and Cognitive Impairment

Introduction

Pain has been identified as a risk factor for cognitive dysfunction, which in turn affects pain perception. Although pain, cognitive dysfunction, and their interaction are clinically important, the neural mechanism connecting the two phenomena remains unclear.

Methods

The resting-state brain activity of 38 participants was measured using magnetoencephalography before and after the patients underwent selective nerve root block (SNRB) for the treatment of their pain. We then assessed the extent to which these data correlated with the subjective levels of pain experienced by the patients across SNRB based on the visual analogue scale and the cognitive status of the patients measured after SNRB using the Japanese versions of the Mini-Mental State Examination (MMSE-J).

Results

Slow oscillations (delta) in the right precentral gyrus, right middle temporal gyrus, and left superior frontal gyrus were negatively correlated with the subjective level of pain, and fast oscillations (gamma) in the right insular cortex and right middle temporal gyrus before SNRB were negatively correlated with the MMSE-J score afterwards. These correlations disappeared after SNRB.

Conclusion

The presently observed changes in neural activity, as indicated by oscillation changes, might represent the transient bridge between pain and cognitive dysfunction in patients with severe pain. Our findings underscore the importance of treating pain before a transient diminishment of cognitive function becomes persistent.

Automated vs. manual pain coding and heart rate estimations based on videos of older adults with and without dementia

Introduction

Technological advances have allowed for the estimation of physiological indicators from video data. FaceReader™ is an automated facial analysis software that has been used widely in studies of facial expressions of emotion and was recently updated to allow for the estimation of heart rate (HR) using remote photoplethysmography (rPPG). We investigated FaceReader™-based heart rate and pain expression estimations in older adults in relation to manual coding by experts.

Methods

Using a video dataset of older adult patients with and without dementia, we assessed the relationship between FaceReader’s™ HR estimations against a well-established Video Magnification (VM) algorithm during baseline and pain conditions. Furthermore, we examined the correspondence between the Facial Action Coding System (FACS)-based pain scores obtained through FaceReader™ and manual coding.

Results

FaceReader’s™ HR estimations were correlated with VM algorithm in baseline and pain conditions. Non-verbal FaceReader™ pain scores and manual coding were also highly correlated despite discrepancies between the FaceReader™ and manual coding in the absolute value of scores based on pain-related facial action coding of the events preceding and following the pain response.

Conclusions

Compared to expert manual FACS coding and optimized VM algorithm, FaceReader™ showed good results in estimating HR values and non-verbal pain scores.

Genuine Smiles by Patients During Marital Interactions are Associated with Better Caregiver Mental Health

OBJECTIVE

Providing care for a spouse with dementia is associated with an increased risk for poor mental health. To determine whether this vulnerability in caregivers is related to the expression of positive emotion, we examined 57 patients with Alzheimer's disease and behavioral variant frontotemporal dementia and their spouses as they discussed a marital conflict.

METHOD

Facial behavior during the discussion was objectively coded to identify Duchenne (i.e., genuine) smiles and non-Duchenne (i.e., polite) smiles. Caregiver mental health was measured using the Medical Outcomes Survey.

RESULTS

Greater expression of Duchenne smiles by patients was associated with better caregiver mental health, even when accounting for covariates (i.e., diagnosis, patient cognitive functioning, and caregiver marital satisfaction). Greater expression of non-Duchenne smiles by patients was associated with worse caregiver health, but only when covariates were entered in the model. Expression of Duchenne and non-Duchenne smiles by caregivers was not associated with caregiver mental health.

DISCUSSION

Patients' expression of Duchenne and non-Duchenne smiles may reveal important aspects of the emotional quality of the patient-caregiver relationship that influence caregiver burden and mental health.

Facial muscle movements encoding pain-a systematic review

Facial expressions of pain are not undefined grimaces, but they convey specific information about the internal state of the individual in pain. With this systematic review, we aim to answer the question of which facial movements are displayed most consistently during pain. We searched for studies that used the Facial Action Coding System to analyze facial activity during pain in adults, and that report on distinct facial responses (action units [AUs]). Twenty-seven studies using experimental pain and 10 clinical pain studies were included. We synthesized the data by taking into consideration (1) the criteria used to define whether an AU is pain-related; (2) types of pain; and (3) the cognitive status of the individuals. When AUs were selected as being pain-related based on a "pain > baseline" increase, a consistent subset of pain-related AUs emerged across studies: lowering the brows (AU4), cheek raise/lid tightening (AUs6_7), nose wrinkling/raising the upper lip (AUs9_10), and opening of the mouth (AUs25_26_27). This subset was found independently of the cognitive status of the individuals and was stable across clinical and experimental pain with only one variation, namely that eye closure (AU43) occurred more frequently during clinical pain. This subset of pain-related facial responses seems to encode the essential information about pain available in the face. However, given that these pain-related AUs are most often not displayed all at once, but are differently combined, health care professionals should use a more individualized approach, determining which pain-related facial responses an individual combines and aggregates to express pain, instead of erroneously searching for a uniform expression of pain.

Pain Expressions in Dementia: Validity of Observers' Pain Judgments as a Function of Angle of Observation

Facial expressions of pain are important in assessing individuals with dementia and severe communicative limitations. Though frontal views of the face are assumed to allow for the most valid and reliable observational assessments, the impact of viewing angle is unknown. We video-recorded older adults with and without dementia using cameras capturing different observational angles (e.g., front vs. profile view) both during a physiotherapy examination designed to identify painful areas and during a baseline period. Facial responses were coded using the fine-grained Facial Action Coding System, as well as a systematic clinical observation method. Coding was conducted separately for panoramic (incorporating left, right, and front views), and a profile view of the face. Untrained observers also judged the videos in a laboratory setting. Trained coder reliability was satisfactory for both the profile and panoramic view. Untrained observer judgments from a profile view were substantially more accurate compared to the front view and accounted for more variance in differentiating non-painful from painful situations. The findings add specificity to the communications models of pain (clarifying factors influencing observers' ability to decode pain messages). Perhaps more importantly, the findings have implications for the development of computer vision algorithms and vision technologies designed to monitor and interpret facial expressions in a pain context. That is, the performance of such automated systems is heavily influenced by how reliably these human annotations could be provided and, hence, evaluation of human observers' reliability, from multiple angles of observation, has implications for machine learning development efforts.

Validation of the Rotterdam Elderly Pain Observation Scale in the Hospital Setting

BACKGROUND

The Rotterdam Elderly Pain Observation Scale (REPOS) has been proven useful to assess pain in noncommunicative and cognitively impaired nursing home residents. We evaluated whether the REPOS is also reliable and valid for pain assessment in the hospital setting.

METHODS

In this prospective multicenter observational study, surgical patients were observed perioperatively at bedside and internal medicine patients were filmed during a possible painful moment and at rest. Pain behavior was assessed from the video recordings with the REPOS and the Pain Assessment Checklist for seniors with Severe Dementia-Dutch language (PACSLAC-D). Longitudinal associations between REPOS score and numeric rating scale pain ratings from observers and nurses (NRS_obs and NRS_proxy ) corrected for patients' gender were assessed with linear mixed models.

RESULTS

In total, 72 patients were included; 118 observations of surgical and 68 observations of internal medicine patients were analyzed. Interobserver reliability between the researcher and 2 other observers was good, with Cohen's kappa values of 0.71 (confidence interval [CI] 0.59 to 0.83) and 0.84 (CI 0.74 to 0.94), respectively. The intraobserver reliability of the principal investigator was good, with Cohen's kappa 0.82 (CI 0.67 to 0.91). Linear mixed modeling revealed correlation values between the REPOS and NRS_obs of 0.67 and the REPOS and NRS_proxy of 0.73. Optimal sensitivity (78%) and specificity (90%) for the detection of pain were found with a REPOS cutoff score of ≥3, using an NRS score of ≥4 as the reference value.

CONCLUSIONS

The REPOS is reliable and valid for the assessment of postoperative and chronic pain in hospital patients who cannot self-report pain.

Psychometric Evaluation of the Electronic Pain Assessment Tool: An Innovative Instrument for Individuals with Moderate-to-Severe Dementia

BACKGROUND/AIMS

Pain is common in aged care residents with dementia; yet it often goes undetected. A novel tool, the electronic Pain Assessment Tool (ePAT), was developed to address this challenging problem. We investigated the psychometric properties of the ePAT.

METHODS

In a 10-week prospective observational study, the ePAT was evaluated by comparison against the Abbey Pain Scale (APS). Pain assessments were blindly co-performed by the ePAT rater against the nursing staff of two residential aged care facilities. The residents were assessed twice by each rater: at rest and following movement.

RESULTS

The study involved 34 residents aged 85.5 ± 6.3 years, predominantly with severe dementia (Psychogeriatric Assessment Scale - Cognitive Impairment score = 19.7 ± 2.5). Four hundred paired assessments (n = 204 during rest; n = 196 following movement) were performed. Concurrent validity (r = 0.911) and all reliability measures (κw = 0.857; intraclass correlation coefficient = 0.904; α = 0.950) were excellent, while discriminant validity and predictive validity were good.

CONCLUSION

The ePAT is a suitable tool for the assessment of pain in this vulnerable population.

A novel pain assessment tool incorporating automated facial analysis: interrater reliability in advanced dementia

OBJECTIVES

Regardless of its severity, dementia does not negate the experience of pain. Rather, dementia hinders self-reporting mechanisms in affected individuals because they lose the ability to do so. The primary aim of this study was to examine the interrater reliability of the electronic Pain Assessment Tool (ePAT) among raters when assessing pain in residents with moderate-to-severe dementia. Secondly, it sought to examine the relationship between total instrument scores and facial scores, as determined by automated facial expression analysis.

STUDY DESIGN

A 2-week observational study.

SETTING

An accredited, high-care, and dementia-specific residential aged care facility in Perth, Western Australia.

PARTICIPANTS

Subjects were 10 residents (age range: 63.1-84.4 years old) predominantly with severe dementia (Dementia Severity Rating Scale score: 46.3±8.4) rated for pain by 11 aged care staff. Raters (female: 82%; mean age: 44.1±12.6 years) consisted of one clinical nurse, four registered nurses, five enrolled nurses, and one care worker.

MEASUREMENTS

ePAT measured pain using automated detection of facial action codes and recordings of pain behaviors.

RESULTS

A total of 76 assessments (rest =38 [n=19 pairs], movement =38 [n=19 pairs]) were conducted. At rest, raters' agreement was excellent on overall total scores (coefficient of concordance =0.92 [95% CI: 0.85-0.96]) and broad category scores (κ=1.0). Agreement was moderate (κ=0.59) on categorical scores upon movement, while it was exact in 68.4% of the cases. Agreement in actual pain category scores gave κw=0.72 (95% CI: 0.58-0.86) at rest and κw=0.69 (95% CI: 0.50-0.87) with movement. All raters scored residents with higher total scores post-mobilization compared to rest. More facial action unit codes were also detected during pain (mean: 2.5 vs 1.9; p<0.0012) and following mobilization (mean: 2.5 vs 1.7; p<0.0001) compared to no pain and rest, respectively.

CONCLUSIONS

ePAT, which combines automated facial expression analysis and clinical behavioral indicators in a single observational pain assessment tool, demonstrates good reliability properties, which supports its appropriateness for use in residents with advanced dementia.

Revealing brain mechanisms of mTOR-mediated translational regulation: Implications for chronic pain

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mTOR is a major regulator of protein translation.

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mTOR serves an important role in neural plasticity.

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mTOR signalling in the brain as a pathology for neurological disorder is known.

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mTOR signalling in the brain as a chronic pain mechanism is understudied.

In the spinal cord, altered protein transcription and translation have received a lot of recent attention for their role in neural plasticity, a major mechanism leading to the development of chronic pain. However, changes in brain plasticity are also associated with the maintenance of pain symptoms, but these cellular mechanisms remain less clear. The mechanistic/mammalian target of rapamycin (mTOR) is a master regulator of protein synthesis, and controls several neuronal functions, including neural plasticity. While aberrant changes in mTOR signaling are associated with sensitization of the pain pathway (sensory neurons and spinal cord), there are various nervous system diseases that have pain as a comorbidity and altered mTOR activity in the brain. Here, we provide a brief review of mTOR changes in the brain that are associated with some neurological disorders and focus on how these changes may be relevant to the pain of the underlying condition and chronic pain itself.

Pain in severe dementia: A comparison of a fine-grained assessment approach to an observational checklist designed for clinical settings

Background

Fine‐grained observational approaches to pain assessment (e.g. the Facial Action Coding System; FACS) are used to evaluate pain in individuals with and without dementia. These approaches are difficult to utilize in clinical settings as they require specialized training and equipment. Easy‐to‐use observational approaches (e.g. the Pain Assessment Checklist for Limited Ability to Communicate‐II; PACSLAC‐II) have been developed for clinical settings. Our goal was to compare a FACS‐based fine‐grained system to the PACSLAC‐II in differentiating painful from non‐painful states in older adults with and without dementia.

Method

We video‐recorded older long‐term care residents with dementia and older adult outpatients without dementia, during a quiet baseline condition and while they took part in a physiotherapy examination designed to identify painful areas. Videos were coded using pain‐related behaviours from the FACS and the PACSLAC‐II.

Results

Both tools differentiated between painful and non‐painful states, but the PACSLAC‐II accounted for more variance than the FACS‐based approach. Participants with dementia scored higher on the PACSLAC‐II than participants without dementia.

Conclusion

The results suggest that easy‐to‐use observational approaches for clinical settings are valid and that there may not be any clinically important advantages to using more resource‐intensive coding approaches based on FACS. We acknowledge, as a limitation of our study, that we used as baseline a quiet condition that did not involve significant patient movement. In contrast, our pain condition involved systematic patient movement. Future research should be aimed at replicating our results using a baseline condition that involves non‐painful movements.

Significance

Examining older adults with and without dementia, a brief observational clinical approach was found to be valid and accounted for more variance in differentiating pain‐related and non‐pain‐related states than did a detailed time‐consuming fine‐grained approach.

Pain in Dementia: Use of Observational Pain Assessment Tools by People Who Are Not Health Professionals

Objective

Pain is prevalent among older adults but is often underestimated and undertreated, especially in people with severe dementia who have limited ability to self-report pain. Pain in patients with moderate to severe dementia can be assessed using observational tools. Informal caregivers (relatives of seniors with dementia) are an untapped assessor group who often bear the responsibility of care for their loved ones. Our objective was to evaluate the ability of laypeople to assess pain using observational measures originally developed for use by health care professionals.

Design

We employed a quasi-experimental design and presented videos depicting patients with dementia (portrayed by actors) displaying pain behaviors or during a calm relaxed state (no pain) to long-term care nurses and laypeople. Participants rated the pain behaviors observed in each video by completing two standardized observational measures that had been previously developed for use by long-term care staff.

Results

As expected, both laypeople and nurses were able to effectively differentiate painful from nonpainful situations using the standardized tools. Both groups were also able to discriminate among gradations of pain (i.e., no pain, mild, moderate, severe) and required comparable amounts of time to complete the assessments.

Conclusions

We conclude that, as hypothesized, the instruments under study can be used for the assessment of pain by laypeople. This is the first study to validate these instruments for use by laypeople. The use of these tools by laypeople (under the guidance of health professionals) has the potential of facilitating earlier detection and treatment of pain in older adults with dementia who live in community settings.

Contextual influences on pain communication in couples with and without a partner with chronic pain

This is an experimental study of pain communication in couples. Despite evidence that chronic pain in one partner impacts both members of the dyad, dyadic influences on pain communication have not been sufficiently examined and are typically studied based on retrospective reports. Our goal was to directly study contextual influences (ie, presence of chronic pain, gender, relationship quality, and pain catastrophizing) on self-reported and nonverbal (ie, facial expressions) pain responses. Couples with (n = 66) and without (n = 65) an individual with chronic pain (ICP) completed relationship and pain catastrophizing questionnaires. Subsequently, one partner underwent a pain task (pain target, PT), while the other partner observed (pain observer, PO). In couples with an ICP, the ICP was assigned to be the PT. Pain intensity and PO perceived pain intensity ratings were recorded at multiple intervals. Facial expressions were video recorded throughout the pain task. Pain-related facial expression was quantified using the Facial Action Coding System. The most consistent predictor of either partner's pain-related facial expression was the pain-related facial expression of the other partner. Pain targets provided higher pain ratings than POs and female PTs reported and showed more pain, regardless of chronic pain status. Gender and the interaction between gender and relationship satisfaction were predictors of pain-related facial expression among PTs, but not POs. None of the examined variables predicted self-reported pain. Results suggest that contextual variables influence pain communication in couples, with distinct influences for PTs and POs. Moreover, self-report and nonverbal responses are not displayed in a parallel manner.

Gaps in Aging Research as it Applies to Rheumatologic Clinical Care

The incidence and prevalence of rheumatologic conditions are increasing and the rheumatology workforce must be aware of aging-specific issues. This article reviews specific barriers to understanding the biology of aging and aging-related mechanisms that may underlie development of rheumatologic diseases in older adults. It summarizes gaps in the assessment, outcomes measurement, and treatment of these diseases in this unique population. It also highlights potential solutions to these barriers and suggests possible ways to bridge the gap, from a research and education standpoint, so that clinicians can be better prepared to effectively manage older adults with rheumatologic conditions.

Contact heat sensitivity and reports of unpleasantness in communicative people with mild to moderate cognitive impairment in Alzheimer's disease: a cross-sectional study

BACKGROUND

Compared to healthy controls, people with Alzheimer's disease (AD) have been shown to receive less pain medication and report pain less frequently. It is unknown if these findings reflect less perceived pain in AD, an inability to recognize pain, or an inability to communicate pain.

METHODS

To further examine aspects of pain processing in AD, we conducted a cross-sectional study of sex-matched adults ≥65 years old with and without AD (AD: n = 40, female = 20, median age = 75; control: n = 40, female = 20, median age = 70) to compare the psychophysical response to contact-evoked perceptual heat thresholds of warmth, mild pain, and moderate pain, and self-reported unpleasantness for each percept.

RESULTS

When compared to controls, participants with AD required higher temperatures to report sensing warmth (Cohen's d = 0.64, p = 0.002), mild pain (Cohen's d = 0.51, p = 0.016), and moderate pain (Cohen's d = 0.45, p = 0.043). Conversely, there were no significant between-group differences in unpleasantness ratings (p > 0.05).

CONCLUSIONS

The between-group findings demonstrate that when compared to controls, people with AD are less sensitive to the detection of thermal pain but do not differ in affective response to the unpleasant aspects of thermal pain. These findings suggest that people with AD may experience greater levels of pain and potentially greater levels of tissue or organ damage prior to identifying and reporting injury. This finding may help to explain the decreased frequency of pain reports and consequently a lower administration of analgesics in AD.

The use of facial expressions for pain assessment purposes in dementia: a narrative review

Facial expressions convey reliable nonverbal signals about pain and thus are very useful for assessing pain in patients with limited communicative ability, such as patients with dementia. In this review, we present an overview of the available pain observation tools and how they make use of facial expressions. Utility and reliability of facial expressions to measure pain in dementia are discussed, together with the effect of dementia severity on these facial expressions. Next, we present how behavioral alterations may overlap with facial expressions of pain, and may even influence the extent to which pain is facially expressed. The main focus is on disinhibition, apathy and emotional changes. Finally, an overview of theoretical considerations and practical implications is presented for assessing pain using facial expressions in clinical settings.

Contact Heat Evoked Potentials (CHEPs) in Patients with Mild-Moderate Alzheimer's Disease and Matched Control--A Pilot Study

OBJECTIVE

Clinical studies have found that patients with Alzheimer's disease report pain of less intensity and with a lower affective response, which has been thought to be due to altered pain processing. The authors wished to examine the cerebral processing of non-painful and painful stimuli using somatosensory evoked potentials and contact heat evoked potentials in patients with Alzheimer's disease and in healthy elderly controls.

DESIGN

Case-control study

SETTING AND SUBJECTS

Twenty outpatients with mild-moderate Alzheimer's disease and in 17 age- and gender-matched healthy controls were included

METHOD

Contact heat evoked potentials and somatosensory evoked potentials were recorded in all subjects. Furthermore, warmth detection threshold and heat pain threshold were assessed. Patients and controls also rated quality and intensity of the stimuli.

RESULTS

The authors found no difference on contact heat evoked potential amplitude (P = 0.59) or latency of N2 or P2 wave (P = 0.62 and P = 0.75, respectively) between patients and controls. In addition, there was no difference in regard to pain intensity scores or pain quality. The patients and controls had similar warmth detection threshold and heat pain threshold. Somatosensory evoked potentials, amplitude, and latency were within normal range and similar for the two groups.

CONCLUSIONS

The findings suggest that the processing of non-painful and painful stimuli is preserved in patients with mild to moderate Alzheimer's disease.

[Pain assessment using the Facial Action Coding System. A systematic review]

Self-reporting is the most widely used pain measurement tool, although it may not be useful in patients with loss or deficit in communication skills. The aim of this paper was to undertake a systematic review of the literature of pain assessment through the Facial Action Coding System (FACS). The initial search found 4,335 references and, within the restriction «FACS», these were reduced to 40 (after exclusion of duplicates). Finally, only 26 articles meeting the inclusion criteria were included. Methodological quality was assessed using the GRADE system. Most patients were adults and elderly health conditions, or cognitive deficits and/or chronic pain. Our conclusion is that FACS is a reliable and objective tool in the detection and quantification of pain in all patients.

Pain management in patients with dementia

There are an estimated 35 million people with dementia across the world, of whom 50% experience regular pain. Despite this, current assessment and treatment of pain in this patient group are inadequate. In addition to the discomfort and distress caused by pain, it is frequently the underlying cause of behavioral symptoms, which can lead to inappropriate treatment with antipsychotic medications. Pain also contributes to further complications in treatment and care. This review explores four key perspectives of pain management in dementia and makes recommendations for practice and research. The first perspective discussed is the considerable uncertainty within the literature on the impact of dementia neuropathology on pain perception and processing in Alzheimer's disease and other dementias, where white matter lesions and brain atrophy appear to influence the neurobiology of pain. The second perspective considers the assessment of pain in dementia. This is challenging, particularly because of the limited capacity of self-report by these individuals, which means that assessment relies in large part on observational methods. A number of tools are available but the psychometric quality and clinical utility of these are uncertain. The evidence for efficient treatment (the third perspective) with analgesics is also limited, with few statistically well-powered trials. The most promising evidence supports the use of stepped treatment approaches, and indicates the benefit of pain and behavioral interventions on both these important symptoms. The fourth perspective debates further difficulties in pain management due to the lack of sufficient training and education for health care professionals at all levels, where evidence-based guidance is urgently needed. To address the current inadequate management of pain in dementia, a comprehensive approach is needed. This would include an accurate, validated assessment tool that is sensitive to different types of pain and therapeutic effects, supported by better training and support for care staff across all settings.

Facial expression as an indicator of pain in critically ill intubated adults during endotracheal suctioning

BACKGROUND

Facial expression is often used to evaluate pain in noncommunicative critically ill patients.

OBJECTIVES

To describe facial behavior during endotracheal suctioning, determine facial behaviors that characterize the pain response, and describe the effect of patient factors on facial behavior during pain response.

METHODS

Fifty noncommunicative patients receiving mechanical ventilation were video recorded during 2 phases (rest and endotracheal suctioning). Pain ratings were gathered by using the Behavioral Pain Scale. Facial behaviors were coded by using the Facial Action Coding System for 30 seconds for each phase.

RESULTS

Fourteen facial actions were associated more with endotracheal suctioning than with rest (z = 5.78; P < .001). The sum of intensity of the 14 actions correlated with total mean scores on the Behavioral Pain Scale (ρ = 0.71; P < .001) and with the facial expression component of the scale (ρ = 0.67; P < .001) during suctioning. In stepwise multivariate analysis, 5 pain-relevant facial behaviors (brow raiser, brow lower, nose wrinkling, head turned right, and head turned up) accounted for 71% of the variance (adjusted R² = 0.682; P < .001) in pain response. The sum of intensity of the 5 actions correlated with total mean scores on the behavioral scale (ρ = 0.72; P < .001) and with the facial expression component of that scale (ρ = 0.61; P < .001) during suctioning. Patient factors had no association with pain intensity scores.

CONCLUSIONS

Upper facial expressions are most frequently activated during pain response in noncommunicative critically ill patients and might be a valid alternative to self-report ratings.

Development and mixed-methods evaluation of a pain assessment video training program for long-term care staff

INTRODUCTION

Inadequacies in pain assessment and management in long-term care have been well documented. Insufficient pain education and inaccurate beliefs about the nature of pain and aging have been identified as possible contributors. The present study addresses the need for improved, efficient and feasible continuing pain education through the use of an assessment training video.

METHODS

A total of 148 long-term care staff viewed and evaluated the training video. Knowledge changes and pain beliefs were assessed postvideo and at a four-week follow-up. Beliefs about pain, as well as pain and aging, were also examined using multivariate procedures to determine whether these variables influenced participants' evaluation of the video. Focus groups were also conducted, and transcripts were analyzed using thematic content analysis.

RESULTS

Pain assessment knowledge improved postvideo and at the four-week follow-up. Participants positively evaluated the content and quality of the video. Individuals who held stronger beliefs (at baseline) about the organic nature of pain provided more positive evaluations. Barriers to implementation of practices in the video identified by the focus groups (and qualitative analysis) included time, workload and resistance to change. Facilitators to implementation included continued management support and observing the benefits to implementation.

DISCUSSION

The present study provides support for the use of video training. However, based on the focus group results, top-down implementation approaches with ongoing management involvement throughout the implementation process may be needed to achieve sustained changes in pain assessment practices. A model useful for sustained implementation was proposed and discussed, and is hoped to facilitate future research.

Automatic detection of pain intensity

Previous efforts suggest that occurrence of pain can be detected from the face. Can intensity of pain be detected as well? The Prkachin and Solomon Pain Intensity (PSPI) metric was used to classify four levels of pain intensity (none, trace, weak, and strong) in 25 participants with previous shoulder injury (McMaster-UNBC Pain Archive). Participants were recorded while they completed a series of movements of their affected and unaffected shoulders. From the video recordings, canonical normalized appearance of the face (CAPP) was extracted using active appearance modeling. To control for variation in face size, all CAPP were rescaled to 96×96 pixels. CAPP then was passed through a set of Log-Normal filters consisting of 7 frequencies and 15 orientations to extract 9216 features. To detect pain level, 4 support vector machines (SVMs) were separately trained for the automatic measurement of pain intensity on a frame-by-frame level using both 5-folds cross-validation and leave-one-subject-out cross-validation. F1 for each level of pain intensity ranged from 91% to 96% and from 40% to 67% for 5-folds and leave-one-subject-out cross-validation, respectively. Intra-class correlation, which assesses the consistency of continuous pain intensity between manual and automatic PSPI was 0.85 and 0.55 for 5-folds and leave-one-subject-out cross-validation, respectively, which suggests moderate to high consistency. These findings show that pain intensity can be reliably measured from facial expression in participants with orthopedic injury.

Behavioral cues to expand a pain model of the cognitively impaired elderly in long-term care

BACKGROUND

The purpose of this study was to determine the relationship between hypothesized pain behaviors in the elderly and a measurement model of pain derived from the Minimum Data Set-Resident Assessment Instrument (MDS-RAI) 2.0 items.

METHODS

This work included a longitudinal cohort recruited from Medicare-certified longterm care facilities across the United States. MDS data were collected from 52,996 residents (mean age 83.7 years). Structural equation modeling was used to build a measurement model of pain to test correlations between indicators and the fit of the model by cognitive status. The model evaluates the theoretical constructs of pain to improve how pain is assessed and detected within cognitive levels.

RESULTS

Using pain frequency and intensity as the only indicators of pain, the overall prevalence of pain was 31.2%; however, analysis by cognitive status showed that 47.7% of the intact group was in pain, while only 18.2% of the severely, 29.4% of the moderately, and 39.6% of the mildly cognitively impaired groups were experiencing pain. This finding supports previous research indicating that pain is potentially under-reported in severely cognitively impaired elderly nursing home residents. With adjustments to the measurement model, a revised format containing affective, behavioral, and inferred pain indicates a better fit of the data to include these domains, as a more complete measure of the pain construct.

CONCLUSION

Pain has a significant effect on quality of life and long-term health outcomes in nursing home residents. Patients most at risk are those with mild to severe cognitive decline, or those unable to report pain verbally. Nursing homes are under great scrutiny to maintain standards of care and provide uniform high-quality care outcomes. Existing data from federally required resident surveys can serve as a valuable tool to identify indicators of pain and trends in care. Great responsibility lies in ensuring pain is included and monitored as a quality measure in long-term care, especially for residents unable to communicate their pain verbally.

Emotional reactivity and awareness of task performance in Alzheimer's disease

Lack of awareness about performance in tasks is a common feature of Alzheimer's disease. Nevertheless, clinical anecdotes have suggested that patients may show emotional or behavioural responses to the experience of failure despite reporting limited awareness, an aspect which has been little explored experimentally. The current study investigated emotional reactions to success or failure in tasks despite unawareness of performance in Alzheimer's disease. For this purpose, novel computerised tasks which expose participants to systematic success or failure were used in a group of Alzheimer's disease patients (n=23) and age-matched controls (n=21). Two experiments, the first with reaction time tasks and the second with memory tasks, were carried out, and in each experiment two parallel tasks were used, one in a success condition and one in a failure condition. Awareness of performance was measured comparing participant estimations of performance with actual performance. Emotional reactivity was assessed with a self-report questionnaire and rating of filmed facial expressions. In both experiments the results indicated that, relative to controls, Alzheimer's disease patients exhibited impaired awareness of performance, but comparable differential reactivity to failure relative to success tasks, both in terms of self-report and facial expressions. This suggests that affective valence of failure experience is processed despite unawareness of task performance, which might indicate implicit processing of information in neural pathways bypassing awareness.

The assessment of post-vasectomy pain in mice using behaviour and the Mouse Grimace Scale

BACKGROUND

Current behaviour-based pain assessments for laboratory rodents have significant limitations. Assessment of facial expression changes, as a novel means of pain scoring, may overcome some of these limitations. The Mouse Grimace Scale appears to offer a means of assessing post-operative pain in mice that is as effective as manual behavioural-based scoring, without the limitations of such schemes. Effective assessment of post-operative pain is not only critical for animal welfare, but also the validity of science using animal models.

METHODOLOGY/PRINCIPAL FINDINGS

This study compared changes in behaviour assessed using both an automated system ("HomeCageScan") and using manual analysis with changes in facial expressions assessed using the Mouse Grimace Scale (MGS). Mice (n = 6/group) were assessed before and after surgery (scrotal approach vasectomy) and either received saline, meloxicam or bupivacaine. Both the MGS and manual scoring of pain behaviours identified clear differences between the pre and post surgery periods and between those animals receiving analgesia (20 mg/kg meloxicam or 5 mg/kg bupivacaine) or saline post-operatively. Both of these assessments were highly correlated with those showing high MGS scores also exhibiting high frequencies of pain behaviours. Automated behavioural analysis in contrast was only able to detect differences between the pre and post surgery periods.

CONCLUSIONS

In conclusion, both the Mouse Grimace Scale and manual scoring of pain behaviours are assessing the presence of post-surgical pain, whereas automated behavioural analysis could be detecting surgical stress and/or post-surgical pain. This study suggests that the Mouse Grimace Scale could prove to be a quick and easy means of assessing post-surgical pain, and the efficacy of analgesic treatment in mice that overcomes some of the limitations of behaviour-based assessment schemes.

[Pain assessment in patients with dementia]

Recent literature demonstrates that pain in patients with dementia is often undertreated. This can partially be explained by a lack of training in the possibilities of assessing pain in patients with dementia. Subjective reports are the most valid approach for the assessment of the subjective experience of pain and should therefore be preferred over other methods. The assessment of the context, behavior, and physiological markers is advised if the patient is unable to provide a subjective report. Pain assessment scales are useful for documentation and monitoring.

Development and evaluation of the Pain Assessment in the Communicatively Impaired (PACI) tool: part II

Pain is a common symptom for long-term care residents, particularly those in need of palliative care. However, pain assessment in residents who have communication limitations is challenging. A study was conducted with the aim of developing a pain assessment tool that could feasibly be used by direct care providers in long-term care with minimal training yet demonstrating strong psychometric properties. The study used both qualitative and quantitative methods to develop and test the Pain Assessment in the Communicatively Impaired (PACI) tool. Part I of this paper reported on the development phase; this second part reports on the test results. The validity and reliability results of the PACI tool were acceptable, and the convergent validity was moderately strong. A moderate level of interobserver agreement was evident, with kappas ranging from 0.46 to 0.63 for the individual items and a kappa score of 0.59 for the total tool score. The overall results of this study support the psychometric properties and feasibility of the PACI tool, offering preliminary support for its use in clinical practice.