Quantity of Movement as a Measure of Engagement for Dementia: The Influence of Motivational Disorders

Socially Assistive Robots for patients with Alzheimer's Disease: A scoping review

BACKGROUND

The most common form of dementia, Alzheimer's Disease (AD), is challenging for both those affected as well as for their care providers, and caregivers. Socially assistive robots (SARs) offer promising supportive care to assist in the complex management associated with AD.

OBJECTIVES

To conduct a scoping review of published articles that proposed, discussed, developed or tested SAR for interacting with AD patients.

METHODS

We performed a scoping review informed by the methodological framework of Arksey and O'Malley and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist for reporting the results. At the identification stage, an information specialist performed a comprehensive search of 8 electronic databases from the date of inception until January 2022 in eight bibliographic databases. The inclusion criteria were all populations who recive or provide care for AD, all interventions using SAR for AD and our outcomes of inteerst were any outcome related to AD patients or care providers or caregivers. All study types published in the English language were included.

RESULTS

After deduplication, 1251 articles were screened. Titles and abstracts screening resulted to 252 articles. Full-text review retained 125 included articles, with 72 focusing on daily life support, 46 on cognitive therapy, and 7 on cognitive assessment.

CONCLUSION

We conducted a comprehensive scoping review emphasizing on the interaction of SAR with AD patients, with a specific focus on daily life support, cognitive assessment, and cognitive therapy. We discussed our findings' pertinence relative to specific populations, interventions, and outcomes of human-SAR interaction on users and identified current knowledge gaps in SARs for AD patients.

The Wellbeing Index for Persons with Dementia-An Observational Study Based on the Group Observational Measurement of Engagement (GOME)

The Group Observational Measurement of Engagement (GOME) was developed to capture the impact of group recreational activities on the engagement and general wellbeing of persons with dementia. The psychometric properties of the GOME were originally described in a study of group activities conducted at one large Canadian geriatric center. Continuing this work in Israel, this article reports on further psychometric properties of the GOME based on observations of 115 persons with dementia from 10 geriatric units, of which four were senior day center units (in three institutions) and six were nursing units (representing five other institutions). Very good inter-rater reliability between research observers was found. Factor analysis suggests that the GOME's four individual-level outcomes can be combined into one indicator, the Wellbeing Index. Validity, examined via agreement between research observers and group activity leaders who were staff members in the facilities where the group activities were conducted, also showed high levels of positive correlations. The GOME provides a practical tool for assessing wellbeing in the context of group activities. It can be useful in clarifying the relative impact of process variables on participants' general wellbeing.

Student arousal, engagement, and emotion relative to Physical Education periods in school

BACKGROUND

Exercise has transient effects on cognition and mood, however the impact of Physical Education (PE) on cognitive and affective processes across the school day has not been examined.

METHOD

This study used wearables and questionnaires to track student arousal, engagement, and emotion across school days/periods following PE. Skin conductance, heart rate, heart rate variability, and self-reported engagement, arousal, and valence were analyzed for 23 students (age 15-17 years) on days with and without PE.

RESULTS

Sympathetic arousal was significantly higher for two hours following PE and there were stronger decreases in arousal across other classes relative to days without PE. On days with PE, engagement decreased, whereas valence increased from morning to afternoon.

CONCLUSION

These findings highlight the importance of considering acute effects of PE on learning across the entire school day, and demonstrates the feasibility of wearables to clarify how the timing of PE could positively or negatively affect self-regulation and learning.

Photo-elicited conversations about meetings with a therapy dog as a tool for communication in dementia care: An observational study

INTRODUCTION

It is well-known that people with dementia living in residential care facilities spend most of their time not engaged in meaningful activities. Being involved in activities can improve their quality of life. Animal-assisted therapy is an activity that can evoke engagement and joy. Another way to create engagement and promote communication between people with dementia and caregivers is to use photos.

METHODS

In this observational study, the researchers combined animal-assisted therapy and photobooks in order to explore whether photos of people with dementia who were engaged in animal-assisted therapy could be used as a tool for communication in dementia care. Ten persons (4 men and 6 women; aged 72-92) with dementia were video recorded during photo-elicited conversations with a dog handler/assistant nurse. The recordings were conducted in two residential care facilities in Sweden during 2017-2018. Each participant was video recorded 2-4 times. The recordings were analysed using The Observed Emotion Rating Scale and The Observational Measurement of Engagement-OME Modified. In addition, the video recordings were interpreted from a hermeneutic perspective.

FINDINGS

The findings showed that the most frequently observed effects were pleasure and general alertness, and the participants were observed to be attentive most of the time. The most common attitude during the conversations was 'somewhat positive'. The hermeneutic interpretations were grouped into four themes: Conveys a structure for the conversation with an inherent beginning and ending; An opportunity to recognise oneself and recall a sense of belonging; Awakens emotions and creates fellowship and Entails confirmation and revitalises their identity.

CONCLUSION

Photobooks can be used by caregivers as a tool for meaningful and joyful communication with people with dementia, even those with severe dementia.

Clinical utility of an assessment scale for engagement in activities for patients with moderate-to-severe dementia: additional analysis

BACKGROUND

We developed the assessment scale for engagement in activities (ASEA), an assessment tool used to quantify engagement in therapeutic activities for patients with moderate-to-severe dementia. In this study, we report additional analyses to confirm the viability of ASEA as a reliable measurement scale.

METHODS

This study included 195 patients with moderate-to-severe dementia in a psychiatric acute-phase hospital. Additional analyses based on the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist were as follows: (i) exploratory and confirmatory factor analysis; (ii) standard error of measurement (SEM), minimal detectable change (MDC) and limit of agreement (LOA); (iii) short change score from baseline to 2 weeks; and (iv) correlation to the facial expression analysis system.

RESULTS

Exploratory factor analysis yielded two factors. This two-factor model of ASEA exhibited an acceptable and validated model fit (comparative fit index = 0.954, Tucker Lewis index = 0.936, goodness-of-fit index = 0.927, adjusted goodness-of-fit index = 0.873, root mean square error of approximation = 0.091, standardised root mean square residual = 0.045) by confirmatory factor analysis. SEM and MDC were 1.29 and 3.80, respectively. The Bland-Altman plot for examining LOA showed no apparent fixed bias. From baseline to 2 weeks later, 129 participants were retested. The mean ASEA total score improved significantly (Wilcoxon signed-rank test; P < 0.01, effect size = 0.25) from baseline (14.30 ± 2.63) to 2 weeks later (15.00 ± 2.73). The correlation between each emotion value was calculated using Kokoro sensor, which is an affect analysis based on human facial expression data using deep learning. For the 36 video data samples, the total score and domains of arousal, interaction, and affect in ASEA were statistically significantly correlated with the emotion value of joy, engagement, and valence (Spearman rank correlation; P < 0.05).

CONCLUSIONS

Among the few evaluation methods specific to severe dementia, ASEA is a useful scale for quantifying and evaluating the state of engagement in therapeutic activities.

Singing and music making: physiological responses across early to later stages of dementia

Background: Music based interventions have been found to improve wellbeing for people with dementia. More recently there has been interest in physiological measures to provide additional information about how music and singing impact this population. Methods: This multiple-case study design explored physiological responses (heart rate-HR, electrodermal activity-EDA, movement, and skin temperature-ST) of nine people with mild-to-moderate using simulation modelling analysis.             Results: In study 1,  the singing group showed an increase in EDA (p < 0.01 for 8/9 participants) and HR (p < 0.01 for 5/9 participants) as the session began. HR (p < 0.0001 for 5/9 participants) and ST (p < 0.0001 for 6/9 participants) increased during faster tempos. EDA (p < 0.01 all), movement (p < 0.01 for 8/9 participants) and engagement were higher during singing compared to a baseline control. In study 2 EDA (p < 0.0001 for 14/18 data points [3 music conditions across 6 participants]) and ST (p < 0.001 for 10/18 data points) increased and in contrast to the responses during singing, HR decreased as the sessions began (p < 0.002 for 9/18 data points). EDA was higher during slower music (p < 0.0001 for 13/18 data points), however this was less consistent in more interactive sessions than the control. There were no consistent changes in HR and movement responses during different music genre.   Conclusions: Physiological measures provide valuable information about the experiences of people with dementia participating in musical activities, particularly for those with verbal communication difficulties. Future research should consider using physiological measures. video-analysis and observational measures to explore further how engagement in specific activities, wellbeing and physiology interact.

Assessing Momentary Well-Being in People Living With Dementia: A Systematic Review of Observational Instruments

Optimizing the possibility to lead good lives is at the core of treatment and care for people with dementia. This may be monitored by assessing well-being and quality of life. However, cognitive impairment following dementia may complicate recall-based assessment with questionnaires, and proxy-ratings from family-caregivers do not correspond well to self-reports. Thus, using observational measures represents a potentially advanced option. Systematic reviews evaluating measurement properties, interpretability and feasibility of observational instruments assessing well-being in people living with dementia are lacking. Thus, this review performed systematic searches to find peer reviewed validated instruments of relevance in the databases MEDLINE, EMBASE, PsycINFO, Web of Science, CINAHL and ProQuest. Twenty-two instruments assessing well-being were included for evaluation of measurement properties based on the systematic approach of the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). The evaluation included risk of bias on study level, and assessment of measurement properties on instrument level including content validity, construct validity, structural validity, internal consistency, measurement invariance, cross-cultural validity, measurement error and inter-rater/intra-rater/test-retest reliability and responsiveness. Additionally, the feasibility and interpretability of the measures were evaluated. No single instrument could be recommended based on existing publications. Thus, we provide general recommendations about further assessment and development of these instruments. Finally, we describe the most promising instruments and offer guidance with respect to their implementation and use in clinical and research contexts.

The LEDs move pilot study: the Light Curtain and physical activity and well-being among people with visual and intellectual disabilities

BACKGROUND

Moving around and being physically active can often be challenging for people with a visual impairment. The combination of a visual and intellectual disability can make being physically active even more difficult. The aim of the current study was to examine whether a technological device for physical activity promotion would be associated with more movement and whether using it would be experienced as enjoyable for people with visual and intellectual disabilities.

METHODS

A randomised multiple baseline design was used for this study. The participants were nine adults with a visual impairment and an IQ between 20 and 50. As participants interacted with the Light Curtain, movement was measured with triaxial accelerometers embedded in the Empatica E4 wristband. Independent observers scored activity, alertness and well-being from video-recordings using the following observation lists: the Happiness Feature Score (HFS) and the Arousal and Valence Scale (AVS).

RESULTS

Physical activity measured with the accelerometer and positive excitement measured with the AVS significantly increased among participants when they were engaged with the Light Curtain compared with care-as-usual activities. Well-being measured with the HFS did not show a significant difference between the baseline and intervention phases.

CONCLUSIONS

Engagement with the Light Curtain increased physical activity and positive excitement in persons with visual and intellectual disabilities, but more research is necessary to understand how the Light Curtain might affect happiness and well-being.

Singing and music making: physiological responses across early to later stages of dementia

Background: Music based interventions have been found to improve the wellbeing of people living with dementia. More recently there has been interest in physiological measures to provide additional information about how music and singing impact this population. Methods: This multiple-case study design explored physiological responses (heart rate-HR, electrodermal activity-EDA, movement, and skin temperature-ST) of nine people with mild-to-moderate dementia during a singing group, and six people in the later stages of dementia during an interactive music group. The interactive music group was also video recorded to provide information about engagement. Data were analysed using simulation modelling analysis.             Results: The singing group showed an increase in EDA (p < 0.01 for 8/9 participants) and HR (p < 0.01 for 5/9 participants) as the session began. HR (p < 0.0001 for 5/9 participants) and ST (p < 0.0001 for 6/9 participants) increased during faster paced songs. EDA (p < 0.01 all), movement (p < 0.01 for 8/9 participants) and engagement were higher during an interactive music group compared to a control session (music listening). EDA (p < 0.0001 for 14/18 participants) and ST (p < 0.001 for 10/18 participants) increased and in contrast to the responses during singing, HR decreased as the sessions began (p < 0.002 for 9/18 participants). EDA was higher during slower music (p < 0.0001 for 13/18 participants), however this was less consistent in more interactive sessions than the control. There were no consistent changes in HR and movement responses during different styles of music.   Conclusions: Physiological measures may provide valuable information about the experiences of people with dementia participating in arts and other activities, particularly for those with verbal communication difficulties. Future research should consider using physiological measures with video-analysis and observational measures to explore further how engagement in specific activities, wellbeing and physiology interact.

Can a humanoid social robot stimulate the interactivity of cognitively impaired elderly? A thorough study based on computer vision methods

Social Assistive Robotics is increasingly being used in care settings to provide psychosocial support and interventions for the elderly with cognitive impairments. Most of these social robots have provided timely stimuli to the elderly at home and in care centres, including keeping them active and boosting their mood. However, previous investigations have registered shortcomings in these robots, particularly in their ability to satisfy an essential human need: the need for companionship. Reports show that the elderly tend to lose interests in these social robots after the initial excitement as the novelty wears out and the monotonous familiarity becomes all too familiar. This paper presents our research facilitating conversations between a social humanoid robot, Nadine, and cognitively impaired elderly at a nursing home. We analysed the effectiveness of human-humanoid interactions between our robot and 14 elderly over 29 sessions. We used both objective tools (based on computer vision methods) and subjective tools (based on observational scales) to evaluate the recorded videos. Our findings showed that our subjects engaged positively with Nadine, suggesting that their interaction with the robot could improve their well-being by compensating for some of their emotional, cognitive, and psychosocial deficiencies. We detected emotions associated with cognitively impaired elderly during these interactions. This study could help understand the expectations of the elderly and the current limitations of Social Assistive Robots. Our research is aligned with all the ethical recommendations by the NTU Institutional Review Board.

Development of the Video Analysis Scale of Engagement (VASE) for people with advanced dementia

Background: The current study sought to develop a valid, reliable and unobtrusive tablet computer-based observational measure to assess engagement of people with advanced dementia. The Video Analysis Scale of Engagement (VASE) was designed to enable the rating of moment-by-moment changes in engagement during an activity, which would be useful for both future research and current residential care.

Methods: An initial version of the VASE was tested. Face validity and content validity were assessed to validate an operational definition of engagement and develop an acceptable protocol for the scale. Thirty-seven non-professional and professional volunteers were recruited to view and rate level of engagement in music activities using the VASE.

Results: An inter-class coefficient (ICC) test gave a high level of rating agreement across professionals and non-professionals.  However, the ICC results of within-professionals were mixed. Linear mixed modelling suggested that the types of interventions (active or passive music listening), the particular intervention session being rated, time period of video and the age of raters could affect the ratings.

Conclusions: Results suggested that raters used the VASE in a dynamic fashion and that the measure was able to distinguish between interventions. Further investigation and adjustments are warranted for this to be considered a valid and reliable scale in the measurement of engagement of people with advanced dementia in a residential care setting.

Development of the Video Analysis Scale of Engagement (VASE) for people with advanced dementia

Background: The current study sought to develop a valid, reliable and unobtrusive tablet computer-based observational measure to assess engagement of people with advanced dementia. The Video Analysis Scale of Engagement (VASE) was designed to enable the rating of moment-by-moment changes in engagement during an activity, which would be useful for both future research and current residential care. Methods: An initial version of the VASE was tested. Face validity and content validity were assessed to validate an operational definition of engagement and develop an acceptable protocol for the scale. Thirty-seven non-professional and professional volunteers were recruited to view and rate level of engagement in music activities using the VASE. Results: An inter-class coefficient (ICC) test gave a high level of rating agreement across professionals and non-professionals.  However, the ICC results of within-professionals were mixed. Linear mixed modelling suggested that the types of interventions (active or passive music listening), the particular intervention session being rated, time period of video and the age of raters could affect the ratings. Conclusions: Results suggested that raters used the VASE in a dynamic fashion and that the measure was able to distinguish between interventions. Further investigation and adjustments are warranted for this to be considered a valid and reliable scale in the measurement of engagement of people with advanced dementia in a residential care setting.

Singing and music making: physiological responses across early to later stages of dementia

Background: Music based interventions have been found to improve the wellbeing of people living with dementia. More recently there has been interest in physiological measures to provide additional information about how music and singing impact this population. Methods: This multiple-case study design explored physiological responses (heart rate-HR, electrodermal activity-EDA, movement, and skin temperature-ST) of nine people with mild-to-moderate dementia during a singing group, and six people in the later stages of dementia during an interactive music group. The interactive music group was also video recorded to provide information about engagement. Data were analysed using simulation modelling analysis.             Results: The singing group showed an increase in EDA (p < 0.01 for 8/9 participants) and HR (p < 0.01 for 5/9 participants) as the session began. HR (p < 0.0001 for 5/9 participants) and ST (p < 0.0001 for 6/9 participants) increased during faster paced songs. EDA (p < 0.01 all), movement (p < 0.01 for 8/9 participants) and engagement were higher during an interactive music group compared to a control session (music listening). EDA (p < 0.0001 for 14/18 participants) and ST (p < 0.001 for 10/18 participants) increased and in contrast to the responses during singing, HR decreased as the sessions began (p < 0.002 for 9/18 participants). EDA was higher during slower music (p < 0.0001 for 13/18 participants), however this was less consistent in more interactive sessions than the control. There were no consistent changes in HR and movement responses during different styles of music.   Conclusions: Physiological measures may provide valuable information about the experiences of people with dementia participating in arts and other activities, particularly for those with verbal communication difficulties. Future research should consider using physiological measures with video-analysis and observational measures to explore further how engagement in specific activities, wellbeing and physiology interact.

Approaches to assessing the impact of robotics in geriatric mental health care: a scoping review

The goals of this scoping literature review are to (1) aggregate the current research involving socially assistive robots in the setting of geriatric psychiatry and (2) examine the outcome measures used in these studies and determine where the gaps and needs are. In light of the global COVID-19 pandemic, the geriatric psychiatric population in particular is vulnerable to both the physical and mental toll COVID-19 may cause. Recently, socially assistive robots have gained attention for their ability to aid in the care of the geriatric psychiatry population and are being explored as a realistic way to deliver certain elements of psychiatric care that have the potential to be safe even in the setting of COVID-19. The results of this review indicate that robots are in the early stages of clinical applicability, they display usability for a range of psychiatric indications, and their impact on clinical care is notable. We project that in the next few years, robotic applications will be tailored to address clinical outcomes with a greater degree of precision and efficacy.

Development of the Video Analysis Scale of Engagement (VASE) for people with advanced dementia

Background: The current study sought to develop a valid, reliable and unobtrusive tablet computer-based observational measure to assess engagement of people with advanced dementia. The Video Analysis Scale of Engagement (VASE) was designed to enable the rating of moment-by-moment changes in engagement during an activity, which would be useful for both future research and current residential care. Methods: An initial version of the VASE was tested. Face validity and content validity were assessed to validate an operational definition of engagement and develop an acceptable protocol for the scale. Thirty-seven non-professional and professional volunteers were recruited to view and rate level of engagement in music activities using the VASE. Results: An inter-class coefficient (ICC) test gave a high level of rating agreement across professionals and non-professionals.  However, the ICC results of within-professionals were mixed. Linear mixed modelling suggested that the types of interventions (active or passive music listening), the particular intervention session being rated, time period of video and the age of raters could affect the ratings. Conclusions: Results suggested that raters used the VASE in a dynamic fashion and that the measure was able to distinguish between interventions. Further investigation and adjustments are warranted for this to be considered a valid and reliable scale in the measurement of engagement of people with advanced dementia in a residential care setting.

Development of an assessment scale for engagement in activities for patients with moderate to severe dementia

BACKGROUND

Various types of therapy, including occupational therapy, are utilised for the treatment of moderate to severe dementia. In order to determine the optimal rehabilitation strategy for such patients and examine the treatment efficacy, an assessment scale for engagement in various group activities that can be easily applied in clinical situations is required. We herein report the development of the Assessment Scale for Engagement in Activities (ASEA) and its clinical utility.

METHODS

The ASEA was developed by nine occupational therapists and a psychiatrist with experience in developing measures for dementia, in accordance with the COSMIN (COnsensus-based Standards for the selection of health status Measurement INstruments) checklist. This assessment comprises 10 items covering four domains: Engagement in the Activity, Interaction, Arousal, and Affect. Participants with moderate to severe dementia who resided in a psychiatric acute phase hospital in Japan were assessed in terms of engagement in activities using the ASEA and Todai-shiki Observational Rating Scale (TORS), and in terms of cognitive function using the Mini-Mental State Examination (MMSE). We examined the internal consistency, inter- and intra-rater reliability, content validity, and concurrent validity of the ASEA.

RESULTS

Cronbach's alpha of the ASEA was 0.889. The overall inter-rater reliability was 0.937 (Spearman rank correlation, P < 0.001), and the intraclass correlation (ICC) for each item was 0.490-0.965 (P < 0.018-0.001). The overall test-retest reliability was 0.778 (Spearman's rank correlation, P < 0.001), and the ICC for each item was 0.498-0.863 (P < 0.023-0.001). The test-retest correlations were significant for almost all items, aside from 'Interaction with others' (P = 0.051). The concurrent validity, examined using the TORS and MMSE, was 0.920 and 0.304 (Spearman's rank correlation, P < 0.001-0.006).

CONCLUSIONS

The ASEA has confirmed reliability and validity, aside from 'Interaction with others' regarding test-retest reliability. Generally, this assessment tool has clinical utility and allows the evaluation of activity engagement among patients with moderate to severe dementia.

Robot-mediated therapy to reduce worrying in persons with visual and intellectual disabilities

BACKGROUND

The study explored the use of a robot-mediated therapeutic intervention in persons with visual and intellectual disabilities.

METHOD

Three robot-mediated intervention sessions were developed to teach three coping skills for worrying. Effectiveness was examined using a multiple-baseline case study design (N = 7). Baseline, pre-intervention and post-intervention assessments included social validity, severity of worrying (PSWQ-C-NL), and observations by caregivers (SDQ). Short checklists on worrying were repeated throughout baseline and intervention stages. Transcripts of the sessions were analysed for participants' emotional openness.

RESULTS

Social validity was equally high before and after the intervention. The intervention did not impact the severity of worrying, although mentor caregivers reported a lower impact of personal difficulties for participants. We found no change in self-disclosure towards the robot over sessions.

CONCLUSIONS

The participants' positive responses warrant further exploration of using robot-mediated therapy for persons with visual and intellectual disabilities. Recommendations for additional adaptations are discussed.

Physical Activity in Severe Dementia Is Associated With Agitation Rather Than Cognitive Function

BACKGROUND

The authors examined associations between physical activity, cognitive function, activities of daily living, and behavioral and psychological dementia symptoms (BPSD) in severe and moderate dementia.

METHODS

A cross-sectional study was conducted to assess severe and moderate dementia groups according to the Clinical Dementia Rating. An actigraphy measured physical activity. Other measures included Mini-Mental State Examination, Cognitive Test for Severe Dementia, Hyogo Activities of Daily Living Scale, and Neuropsychiatric Inventory-Nursing Home.

RESULTS

Sixty-three participants were assessed (mean age = 89.3 ± 6.4). Physical activity was not associated with cognitive function among participants with severe dementia, although there was a trend-level association with cognitive function among those with moderate dementia. Physical activity was significantly associated with BPSD, specifically agitation/aggression symptoms, for participants with severe dementia, and there was a trend-level association with anxiety for participants with moderate dementia.

CONCLUSIONS

Physical activity appears to be associated with BPSD among individuals in the advanced stages of dementia.

Engagement and experience of older people with socially assistive robots in home care

Social isolation is one of the most common consequences of older people with dementia, especially for those who live at their own dwellings alone due to limited access to social activities. Research relating to the use of social robots in aged care has increasing attention to facilitating the support to care services for older people with dementia. Particularly less attention has focused on the applicability of social robots in home care services. This paper aims to study the engagement and robot experience of older people with dementia while interacting with a social robot named Betty in the context of home-based care. This paper contributes to the research relating to care service embedded robots by expanding the knowledge regarding longitudinal research in home based care, while there is limited long-term study in this context. The results show that social robots are evident to be able to engage with older people with dementia at home. Consequently, designing social robots in a social context is desirable. While the robots enabled service for the human partner within the social context is possible, there is a need to underpin the concept of personhood to realize personalization of services and its contents to suit individual preferences.

Understanding Engagement in Dementia Through Behavior. The Ethographic and Laban-Inspired Coding System of Engagement (ELICSE) and the Evidence-Based Model of Engagement-Related Behavior (EMODEB)

Engagement in activities is of crucial importance for people with dementia. State of the art assessment techniques rely exclusively on behavior observation to measure engagement in dementia. These techniques are either too general to grasp how engagement is naturally expressed through behavior or too complex to be traced back to an overall engagement state. We carried out a longitudinal study to develop a coding system of engagement-related behavior that could tackle these issues and to create an evidence-based model of engagement to make meaning of such a coding system. Fourteen elderlies with mild to moderate dementia took part in the study. They were involved in two activities: a game-based cognitive stimulation and a robot-based free play. The coding system was developed with a mixed approach: ethographic and Laban-inspired. First, we developed two ethograms to describe the behavior of participants in the two activities in detail. Then, we used Laban Movement Analysis (LMA) to identify a common structure to the behaviors in the two ethograms and unify them in a unique coding system. The inter-rater reliability (IRR) of the coding system proved to be excellent for cognitive games (kappa = 0.78) and very good for robot play (kappa = 0.74). From the scoring of the videos, we developed an evidence-based model of engagement. This was based on the most frequent patterns of body part organization (i.e., the way body parts are connected in movement) observed during activities. Each pattern was given a meaning in terms of engagement by making reference to the literature. The model was tested using structural equation modeling (SEM). It achieved an excellent goodness of fit and all the hypothesized relations between variables were significant. We called the coding system that we developed the Ethographic and Laban-Inspired Coding System of Engagement (ELICSE) and the model the Evidence-based Model of Engagement-related Behavior (EMODEB). To the best of our knowledge, the ELICSE and the EMODEB constitute the first formalization of engagement-related behavior for dementia that describes how behavior unfolds over time and what it means in terms of engagement.