Motivation in stroke patients for rehabilitation scale

1. Abstract

The Motivation in stroke patients for rehabilitation scale (commonly designated as the MORE scale) represents a landmark development within contemporary rehabilitation psychology and neurorehabilitation psychometrics. Designed to quantitatively measure the motivational intensity and psychological commitment of adult stroke survivors undergoing active convalescent therapy, the instrument resolves persistent methodological shortcomings inherent in conventional assessment strategies. Historically, the evaluation of post-stroke rehabilitation drive has been constrained either by clinician-rated observational instruments—which routinely conflate physical fatigue, motor paresis, or neuro-motor impairment with a genuine absence of psychological engagement—or by generic self-report batteries adapted from athletic or occupational spheres that fail to reflect the existential crisis, functional bereavement, and neurocognitive sequelae characteristic of cerebrovascular accidents. Developed rigorously according to the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) taxonomy and recommendations, the MORE scale establishes a standardized, patient-reported outcome measure (PROM) grounded directly in the lived phenomenology of stroke survivors through mixed-method Delphi consensus and clinical psychometric validation.

The scale encompasses 17 self-report items scored on an authentic 7-point Likert scale ranging from 1 (Strongly disagree) to 7 (Strongly agree), generating a cumulative score between 17 and 119, with higher scores reflecting elevated levels of therapeutic motivation. Psychometrically, the instrument was calibrated using both classical test theory (CTT) and multidimensional/unidimensional item response theory (specifically, Samejima’s Graded Response Model). Although the initial item generation paradigm mapped across diverse ecological facets—including internal goal orientation, personal resilience, emotional processing of functional feedback, and interpersonal alliances with rehabilitation therapists and family—empirical exploratory and confirmatory factor analyses identified an unambiguous, robust unidimensional latent structure. Internal consistency is exceptionally high (Cronbach’s α = 0.948), and temporal stability evaluated across a one-month test-retest interval demonstrates moderate longitudinal reproducibility (Spearman's ρ = 0.612), reflecting the dynamic, state-like responsiveness of recovery drive. The MORE scale displays divergent validity against clinical apathy (Apathy Scale ρ = -0.536) and depressive symptomatology (Zung Self-rating Depression Scale ρ = -0.347), and robust convergent validity with subjective motivational visual analogue scales (ρ = 0.536), rendering it a vital diagnostic and clinical research instrument in post-acute neurorehabilitation.

2. Keywords

stroke rehabilitation, motivation, patient-reported outcome measure, psychometrics, COSMIN, item response theory, cerebrovascular accident, neurorehabilitation, convalescent care, graded response model

3. Authors

The scale was developed and empirically validated by a multidisciplinary research consortium in Japan specializing in physical and rehabilitation medicine, occupational therapy, and psychometric science:

• Taiki Yoshida — Department of Rehabilitation Medicine, Keio University School of Medicine, Tokyo, Japan; Department of Rehabilitation Medicine, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
• Yohei Otaka (Corresponding Author) — Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan. Email: [email protected].
• Shin Kitamura — Department of Rehabilitation Medicine, Keio University School of Medicine, Tokyo, Japan.
• Kazuki Ushizawa — Department of Rehabilitation, Fujita Health University Hospital, Toyoake, Aichi, Japan.
• Masashi Kumagai — Department of Rehabilitation Medicine, Keio University School of Medicine, Tokyo, Japan.
• Yuto Kurihara — Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan.
• Jun Yaeda — Faculty of Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
• Rieko Osu — Faculty of Science and Engineering, Waseda University, Tokyo, Japan.

4. Purpose

Within inpatient neurorehabilitation, therapeutic engagement represents one of the single most influential determinants of long-term functional recovery, neuroplastic reorganization, and community reintegration following a cerebrovascular accident (CVA). Stroke rehabilitation necessitates prolonged, intensive, and physically taxing efforts distributed across multiple therapeutic modalities, including physical therapy, occupational therapy, and speech-language pathology. Despite empirical consensus linking high motivational engagement with superior functional independence measure gains, measuring motivation has long posed severe diagnostic and epistemological challenges for clinical teams.

Prior to the introduction of the MORE scale, clinicians predominantly assessed patient motivation using clinician-administered observation ratings, such as the Pittsburgh Rehabilitation Participation Scale (PRPS), or ad-hoc behavioral checklists. Such observational approaches possess profound systematic vulnerabilities: they inherently confound functional motor impairment, neuromuscular hemiplegia, post-stroke expressive aphasia, cognitive fatigue, and clinical apathy with a deliberate or subjective deficit in psychological drive. A patient who suffers from severe physical exhaustion or apraxia may be misclassified by clinical staff as unmotivated, whereas a compliant but profoundly passive patient may be inaccurately evaluated as possessing high intrinsic drive. Conversely, borrowing psychometric batteries originally developed within sport psychology—such as adaptations of the Sport Motivation Scale (SMS)—or traumatic brain injury tools lacking validation for ischemic and hemorrhagic stroke populations fails to account for the unique psychological devastation, sudden bodily transformation, and functional dependency intrinsic to stroke survivorship.

The primary clinical purpose of the MORE scale is to establish an authentic, self-administered patient-reported outcome measure that directly accesses the survivor's internal phenomenological state, bypassing clinician observational bias. In applied clinical environments, the MORE scale equips physical therapists, occupational therapists, rehabilitation physicians, and clinical neuropsychologists with an objective, standardized metric to detect motivational deficits early in the convalescent phase. Identifying patients with diminished rehabilitation drive enables care teams to deploy tailored psychological, environmental, and behavioral interventions—such as shared goal-setting protocols, self-efficacy training, collaborative therapeutic alliances, or pharmacological reviews for secondary apathy. In research paradigms, the scale serves as a standardized endpoint metric to evaluate the efficacy of motivational interviewing, virtual reality systems, robotic neurorehabilitation therapies, and patient-centered rehabilitation models on sustained patient engagement.

5. Psychological Construct

The latent construct quantified by the MORE scale is defined as rehabilitation motivation: the conscious, goal-directed psychological activation, persistence, and subjective determination of a stroke survivor to participate fully in therapeutic training aimed at functional restitution and psychosocial adaptation.

During the qualitative conceptualization phase, the construct was systematically structured through Delphi consensus panels encompassing stroke survivors and experienced multidisciplinary rehabilitation professionals. This initial mapping parsed the ecological drivers of rehabilitation drive into several interacting experiential dimensions:

• Intrapersonal Determinants and Goal Orientation: This facet reflects internal psychological resolve, cognitive awareness of the mechanistic value of therapeutic exercises, realistic yet ambitious long-term goal setting, and the fundamental aspiration to regain pre-morbid independence and bodily autonomy (e.g., items evaluating determination to regain functional capacity and understanding the therapeutic rationale behind exercises).
• Perceived Functional Progress and Mastery Feedback: Motivational drive is continuously reinforced through the perceived efficacy of therapeutic tasks. When patients observe tangible increments in motor control, gait stability, or manual dexterity, their sense of competence escalates, mitigating post-stroke demoralization (e.g., items focusing on the encouragement derived from observing small clinical improvements).
• Resilience Against Fatigue and Negative Affect: Stroke recovery is inherently non-linear and characterized by severe cognitive and somatic fatigue, emotional lability, and somatic discomfort. This dimension captures the volition necessary to sustain physical and cognitive effort even during days dominated by exhaustion, low mood, or psychological distress.
• Social Support Systems and Interpersonal Alliances: Motivation does not function within an isolated neural system; it is profoundly social. This dimension encapsulates the powerful psychological reinforcement supplied by family members, personal networks, and the reciprocal trust established between the patient and the clinical team (e.g., transparent communication, collaborative goal construction, and genuine empathetic listening from treating clinicians).

Crucially, while the qualitative construct blueprint was conceived as multifaceted across personal and relational spheres, empirical structural analysis demonstrated that among stroke survivors in active inpatient rehabilitation, these diverse personal, social, and functional drivers integrate into a singular, cohesive psychological entity. Rather than operating as compartmentalized or competing motivational modules, personal aspirations, family obligations, and therapeutic alliances synthesize into an undifferentiated latent motivational force that directly fuels rehabilitation engagement.

6. Theoretical Framework

The MORE scale is theoretically anchored at the intersection of Self-Determination Theory (SDT), Bandura’s Self-Efficacy Theory, and modern neurorehabilitation models of goal-directed action.

Self-Determination Theory in Neurorehabilitation

Formulated by Edward L. Deci and Richard M. Ryan, Self-Determination Theory posits that sustained human agency and psychological flourishing depend upon the satisfaction of three fundamental psychological needs: autonomy, competence, and relatedness. In the traumatic context of an acute stroke, all three basic needs are abruptly compromised:

• Autonomy is shattered by sudden physical paralysis, cognitive deficits, and total institutional dependency. The MORE scale captures autonomy restoration through items evaluating the patient’s active participation in setting personalized clinical goals and identifying personally meaningful rehabilitation activities.
• Competence is threatened by loss of basic motor and activities of daily living (ADL) capabilities. The scale taps the competence loop by assessing how recognizing incremental functional improvements validates personal effort and sustains belief in positive recovery outcomes.
• Relatedness is reflected through items capturing the therapeutic alliance and familial encouragement. When clinicians actively listen and provide clear explanations, the patient transitions from being an external, passive recipient of medical care to an autonomous, intrinsically engaged partner in their neuroplastic recovery.

Social Cognitive Theory and Mastery Expectations

Albert Bandura's Social Cognitive Theory underscores that motivation is fundamentally mediated by perceived self-efficacy—an individual's belief in their capability to execute courses of action required to attain designated performances. Within the MORE scale, self-efficacy is explicitly assessed through the survivor’s subjective conviction that their active physical participation makes an authentic difference in long-term functional recovery. This sense of personal agency serves as an essential psychological buffer against learned helplessness, which frequently develops when stroke patients perceive their physical impairments as irreversible.

Distinction from Apathy and Post-Stroke Depression Models

Neurorehabilitation literature has historically grappled with the conceptual overlap between diminished motivation, post-stroke depression (PSD), and organic post-stroke apathy resulting from frontal-subcortical circuit disruption (as characterized by Robert S. Marin and Sergio E. Starkstein). The theoretical premise underpinning the MORE scale posits that rehabilitation motivation is not simply the mirror inverse of apathy or depression. While apathy represents a broad deficit in self-initiated, goal-directed behavior spanning cognitive, behavioral, and emotional domains, rehabilitation motivation reflects context-specific, prospective volition directed specifically at functional restoration, somatic exercise, and identity reconstruction.

7. Validity

The validation methodology of the MORE scale was conducted in full alignment with the international COSMIN guidelines, combining Classical Test Theory with modern Item Response Theory to rigorously evaluate its psychometric properties.

Item Response Theory (IRT) Validation

The researchers fitted Samejima’s Graded Response Model (GRM), an advanced polytomous IRT framework suited for ordered categorical responses. The empirical parameter estimates demonstrated exceptional diagnostic performance across all 17 scale items:

• Item Discrimination Parameters (α): Slopes ranged from 0.811 to 2.142. In psychometric modeling, discrimination values exceeding 0.80 confirm that the items possess strong diagnostic power to distinguish accurately between individuals with low, moderate, and high levels of latent motivation (θ). The upper values (> 1.70) represent exceptionally high discriminative capability.
• Item Difficulty/Threshold Parameters (β): The boundary location parameters ranged from -3.203 to 0.522. This broad distribution on the latent trait continuum demonstrates that the scale effectively assesses motivation across a wide spectrum. The negative skew in threshold parameters indicates high sensitivity for detecting variations among individuals suffering from low-to-moderate motivational states, a primary clinical priority in post-stroke screening.

Convergent and Discriminant Validity Evidence

Construct validity was evaluated against validated standardized psychometric reference instruments in a clinical sample of 201 convalescent stroke survivors:

The statistical independence confirmed by the moderate correlation with the Zung SDS (ρ = -0.347) is especially vital: it confirms that clinicians cannot infer a stroke patient’s rehabilitation drive merely from their depression score, validating the requirement for a dedicated PROM.

8. Reliability

The psychometric evaluation of the MORE scale confirms excellent measurement precision and theoretically sound temporal stability.

Internal Consistency

The scale achieved an overall Cronbach’s alpha of α = 0.948 (frequently rounded to 0.95), indicating outstanding internal consistency. Such a high coefficient corroborates that all 17 items measure the shared latent dimension of rehabilitation motivation with exceptional homogeny and minimal random measurement error. Psychometricians note, however, that an alpha coefficient approaching 0.95 may suggest slight content redundancy among items or reflect an observed ceiling effect. This ceiling phenomenon commonly emerges when stroke patients are evaluated during early inpatient convalescent hospitalization, where optimism, heightened attention from clinical specialists, and initial functional gains often generate high overall motivation scores.

Test-Retest Temporal Stability

Longitudinal stability was examined over a one-month test-retest interval, yielding a Spearman rank correlation coefficient of ρ = 0.612. In traditional psychometrics assessing fixed cognitive or personality traits, a test-retest coefficient of 0.612 might be considered moderate. However, within the substantive context of neurorehabilitation psychology, this moderate coefficient provides critical empirical validation: rehabilitation motivation is fundamentally a state-like, dynamic psychological process rather than an unmodifiable trait. Over the course of 30 days of exhaustive daily physical therapy, patients inevitably experience functional plateaus, neurological recovery, pain flares, and environmental transitions. Thus, a coefficient of ρ = 0.612 demonstrates adequate structural stability while retaining sensitivity to real-world clinical fluctuations.

9. Factor Analysis

To determine the dimensionality and internal architecture of the MORE scale, the developers applied comprehensive exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to the validation cohort.

Exploratory Factor Analysis (EFA)

Prior to extraction, sampling adequacy and inter-item correlation matrices were confirmed using the Kaiser-Meyer-Olkin (KMO) measure and Bartlett's Test of Sphericity. Although qualitative development originated from multiple theoretical pillars (personal resilience, therapeutic relationships, goal orientation), the empirical EFA demonstrated a decisive single-factor dominance:

• The initial eigenvalue of the dominant first factor accounted for the vast majority of the shared variance, dropping sharply to the second eigenvalue (exhibiting a classic scree plot 'elbow' conforming to Kaiser-Guttman criteria).
• All 17 candidate items demonstrated high, unifactorial factor loadings exceeding acceptable psychometric thresholds (> 0.50), without complex or fragmented secondary cross-loadings.

Confirmatory Factor Analysis (CFA)

A subsequent structural equation modeling framework was utilized to verify the fit of the hypothesized unidimensional model. The single-factor model converged successfully, yielding structural fit indices that satisfied standard international thresholds for health status questionnaires:

• Comparative Fit Index (CFI) & Tucker-Lewis Index (TLI): Demonstrated robust adequacy (> 0.90), corroborating that a singular latent factor sufficiently reproduces the sample covariance structure.
• Root Mean Square Error of Approximation (RMSEA): Fell within acceptable parameters, indicating minimal residual error between the observed correlation matrix and the model-implied matrix.
• Standardized Factor Loadings: Every individual item loaded significantly (p < 0.001) onto the unitary latent construct of rehabilitation motivation.

This structural finding conveys substantial clinical meaning: while stroke patients draw motivation from multifaceted ecological sources (family encouragement, internal resolve, clinician empathy), these disparate influences aggregate clinically into a cohesive psychological state. Consequently, scoring the instrument as a single composite index is psychometrically justified.

10. Instrument / Measurement Tool

• Instrument Name: Motivation in stroke patients for rehabilitation scale (MORE scale)
• Test Type: Patient-Reported Outcome Measure (PROM); self-administered standardized psychological rating scale
• Target Population: Adult and older adult stroke survivors (ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage) admitted to acute or convalescent rehabilitation wards
• Item Count: 17 items
• Response Scale: Authentic 7-point Likert scale (1 = Strongly disagree, 2 = Disagree, 3 = Somewhat disagree, 4 = Neither agree nor disagree, 5 = Somewhat agree, 6 = Agree, 7 = Strongly agree)
• Scoring Methodology: Total score is calculated by summing all 17 individual item responses. No items require reverse scoring in the unidimensional model.
• Score Range: 17 to 119 points. Higher cumulative scores indicate greater motivation, commitment, and subjective readiness for physical rehabilitation.
• Administration Time: Approximately 5 to 10 minutes (can be read aloud by an assistant for patients with minor visual or mild non-fluent language impairments, provided no clinician interpretation is injected).
• Language: Originally developed and validated in Japanese; verified English academic translation provided in psychometric source literature.

11. Permissions & Fee and Test Year

The Motivation in stroke patients for rehabilitation scale was formally published in 2022 under the terms of the Creative Commons Attribution (CC BY 4.0) license via the open-access journal PLoS ONE (Yoshida et al., 2022). As an open-access psychometric instrument, it is free of commercial licensing fees for non-profit academic research and clinical healthcare utilization, provided proper scholarly attribution is maintained.

Researchers or rehabilitation health systems planning translation, formal cross-cultural adaptation, or clinical electronic medical record (EMR) integration are encouraged to coordinate directly with the lead corresponding author:

• Yohei Otaka, M.D., Ph.D.
  Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan.
  Email: [email protected]

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13. Items of the Scale