1. Abstract
The Stroke-Adapted Sickness Impact Profile (SA-SIP30) is a condition-specific, health-related quality of life (HRQoL) measurement instrument developed to evaluate functional limitations and psychosocial disruption following a cerebrovascular accident (CVA). Derived from the comprehensive 136-item Sickness Impact Profile (SIP) by Annemieke van Straten and colleagues in 1997, the SA-SIP30 preserves the conceptual rigor of the original behavioral assessment while drastically reducing respondent burden. The inventory consists of 30 dichotomously scored items (checked if true for the respondent due to their health status) covering eight primary functional subscales: Body Care and Movement, Social Interaction, Mobility, Emotional Behavior, Household Management, Alertness Behavior, Ambulation, and Communication. These eight subscales aggregate into two higher-order dimensions—Physical Functioning and Psychosocial Functioning—alongside a global composite index. Extensive psychometric evaluations demonstrate high internal consistency (Cronbach’s alpha spanning 0.85 to 0.94 for the total score), robust test-retest reliability ($r > 0.88$), and superior responsiveness to longitudinal clinical recovery compared to the generic parent instrument. Construct validity is confirmed through strong convergent correlations with neurological impairment measures, functional independence assessments (such as the Barthel Index and the modified Rankin Scale), and subjective wellbeing scales. Designed for self-administration, proxy completion, or structured interview, the SA-SIP30 serves as a pragmatic and psychometrically sound standard for stroke rehabilitation research, clinical trials, and epidemiological outcome monitoring.
2. Keywords
Stroke-Adapted Sickness Impact Profile, SA-SIP30, Sickness Impact Profile, stroke rehabilitation, health-related quality of life, cerebrovascular accident, functional outcome, psychometrics, patient-reported outcome measures, physical disability, psychosocial functioning.
3. Authors
The Stroke-Adapted Sickness Impact Profile was developed by Annemieke van Straten, Ph.D., in collaboration with clinical epidemiologists and neurologists at the Academic Medical Center, University of Amsterdam, Netherlands.
- Annemieke van Straten, Ph.D. — Department of Clinical Epidemiology and Biostatistics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands; currently Professor of Clinical Psychology at Vrije Universiteit Amsterdam, Amsterdam, Netherlands.
- Rob J. de Haan, Ph.D. — Department of Clinical Epidemiology and Biostatistics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.
- Martin Limburg, M.D., Ph.D. — Department of Neurology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.
- Cees A. Schuling, M.D., Ph.D. — Department of Neurology, University Hospital Groningen, Groningen, Netherlands.
4. Purpose
The primary clinical and empirical objective of the Stroke-Adapted Sickness Impact Profile (SA-SIP30) is to provide an efficient, psychometrically robust, and disease-sensitive measure of health status and functional limitation specifically tailored to individuals recovering from stroke. While generic health status measures such as the full 136-item Sickness Impact Profile (SIP) and the Medical Outcomes Study 36-Item Short Form (SF-36) offer broad applicability across systemic illnesses, their application in acute and chronic stroke cohorts is frequently hampered by administrative burdens, irrelevant functional questions, and pronounced floor or ceiling effects.
Stroke survivors often experience profound physical fatigue, post-stroke cognitive slowing, expressive or receptive aphasia, and reduced sustained attention. Administering an exhaustive 136-item questionnaire under such neurological constraints risks significant non-response, respondent frustration, and incomplete data collection. The SA-SIP30 addresses these limitations by distilling the original questionnaire down to the 30 items that demonstrate the highest clinical relevance, discriminative validity, and metric sensitivity to stroke-induced impairments.
In clinical practice, the instrument captures the downstream behavioral consequences of neurological damage across both physical mobility and subtle psychosocial domains, such as social withdrawal, lability of affect, and reduced cognitive alertness. In clinical trial environments, the scale functions as a validated, patient-reported endpoint capable of tracking longitudinal changes following neuroprotective pharmacological therapies, acute thrombolysis, neurorehabilitation protocols, and community reintegration programs. By measuring actual behavioral performance rather than abstract perceived capability, the SA-SIP30 yields objective insight into how patients navigate their daily physical and social environment.
5. Psychological Construct
The SA-SIP30 measures health-related functional impairment based on directly observable behavioral changes precipitated by illness. Rather than evaluating subjective emotional distress or biological organ pathology, the instrument focuses on behavioral modifications across eight discrete domains:
- Body Care and Movement (BCM): Quantifies difficulties in managing personal hygiene, dressing, bathing, and postural stability. Behaviors include requiring assistance to dress, alterations in physical coordination during basic self-care tasks, and reliance on assistive devices for maintaining physical stability.
- Social Interaction (SI): Assesses modifications in interpersonal relationships, social engagement, and voluntary interactions. This domain measures behaviors such as withdrawing from recreational gatherings, limiting communication with friends and family, and showing behavioral isolation within household environments.
- Mobility (M): Evaluates operational confinement and geographical range. Items quantify limitations regarding confinement to the immediate bed or chair, restrictions on leaving the domestic domicile, and dependencies regarding public transit or vehicular travel.
- Emotional Behavior (EB): Reflects behavioral manifestations of affective disruption, psychological distress, and irritability directly attributed to the cerebrovascular condition. Examples include observable weeping, uncharacteristic outbursts of impatience, and verbal expressions of frustration or despair regarding lost physical autonomy.
- Household Management (HM): Assesses performance in domestic maintenance, cleaning, meal preparation, shopping, and everyday financial and logistical organization. It reflects instrumental activities of daily living (IADLs) vital for independent community survival.
- Alertness Behavior (AB): Evaluates executive, cognitive, and attentional aspects of daily behavioral functioning. This includes observable memory lapses, difficulty concentrating on structured tasks (such as reading a newspaper or balancing a checkbook), and errors during complex task execution.
- Ambulation (A): Specifically measures basic locomotion, walking competence, gait abnormalities, and stair negotiation. It captures limitations such as needing a cane or walker, walking at a substantially decreased velocity, and avoiding steps or uneven surfaces.
- Communication (C): Quantifies behavioral impairments in linguistic expression and comprehension, which are highly relevant in post-stroke conditions like dysarthria or mild-to-moderate aphasia. Items assess difficulties in sustaining conversations, articulation impairments, and requiring written alternatives to convey intent.
6. Theoretical Framework
The theoretical architecture of the SA-SIP30 rests upon the behavioral sickness model formulated by Marilyn Bergner and colleagues during the development of the original Sickness Impact Profile. This framework is grounded in functionalism and medical sociology, defining sickness primarily through observable behavioral modifications rather than inner psychological states, biological indicators, or biochemical disease parameters.
According to this behavioral perspective, sickness becomes clinically and socially meaningful when an individual alters their normative daily actions. The focus is specifically on what individuals do or cannot do in response to physical pathology, rather than what they hypothetically feel capable of achieving. This behavioral operationalization minimizes response shifts and cognitive distortions common to general quality of life measures, anchoring self-assessment to concrete daily realities.
The SA-SIP30 also aligns with the International Classification of Functioning, Disability and Health (ICF) conceptualized by the World Health Organization (WHO). Within the ICF architecture, health consequences are parsed across three distinct levels: body structures and functions (impairments), personal activities (limitations), and social participation (restrictions). The SA-SIP30 spans both activity limitations (e.g., ambulation, self-care, meal preparation) and participation restrictions (e.g., social engagement, emotional interaction, domestic maintenance), providing a coherent bridge across ICF domains.
7. Validity
Construct and Convergent Validity
Construct validity for the SA-SIP30 was established by van Straten et al. (1997) across multi-center stroke cohorts by correlating its scores with conventional stroke outcome indices. The SA-SIP30 demonstrated strong convergent validity with the Barthel Index ($r = -0.74$ to $-0.82$, reflecting inverse relationships between functional independence and sickness impact) and the modified Rankin Scale ($r = 0.70$ to $0.78$). Furthermore, the subscales of the SA-SIP30 correlated predictably with the EuroQol (EQ-5D) and SF-36 dimensions, displaying moderate to strong associations ($r = 0.55$ to $0.72$) across analogous physical and mental components.
Discriminant and Known-Groups Validity
Discriminant validity is supported by the instrument’s ability to differentiate between distinct patient subgroups categorized by stroke hemisphere (left versus right hemisphere lesions), neurological severity, and discharge destination (home versus residential nursing care facilities). Patients discharged to chronic rehabilitation institutions or long-term nursing homes yielded significantly higher baseline and 6-month SA-SIP30 scores ($p < 0.001$) than those able to return home immediately. The tool also discriminates between stroke patients with severe motor deficits and those with predominantly lacunar, sensory, or transient attacks.
Predictive Validity and Responsiveness
Longitudinal evaluations demonstrate that the SA-SIP30 exhibits high responsiveness to recovery during the first year post-stroke. In sensitivity analyses calculating the standardized response mean (SRM) and effect size (ES) between three months and one year post-stroke, the SA-SIP30 showed responsive effect sizes ($ES > 0.60$) superior to the generic SIP-136, as uninformative or non-responsive items (e.g., occupational and leisure items irrelevant to older, bed-bound cohorts) were eliminated during scale adaptation.
8. Reliability
Internal Consistency
The SA-SIP30 displays strong internal consistency across varied clinical populations. In the initial validation study conducted by van Straten et al. (1997), Cronbach’s alpha for the composite 30-item scale reached $\alpha = 0.85$ at initial assessment and $\alpha = 0.89$ at six months follow-up. Subsequent validation studies across diverse cultural adaptations (e.g., Italian, Turkish, Brazilian Portuguese, and French) have replicated these metrics, yielding Cronbach’s alpha values between $0.84$ and $0.94$ for the overall composite index. The Physical and Psychosocial sub-dimensions consistently show alpha values between $0.78$ and $0.88$.
Test-Retest and Inter-Rater Reliability
Test-retest stability was evaluated by administering the questionnaire to clinically stable stroke patients across an interval ranging from 7 to 14 days. Intraclass correlation coefficients (ICC) for the total score ranged from $0.88$ to $0.92$, demonstrating high stability in the absence of acute neurological changes. Furthermore, inter-rater reliability across distinct clinical examiners and proxy-patient concordance revealed weighted kappa coefficients ranging from $0.68$ to $0.84$, indicating substantial agreement between patients and trained surrogate respondents when cognitive deficits preclude direct patient response.
9. Factor Analysis
The structural reduction of the original 136-item SIP down to the 30-item stroke-specific tool was guided by clinical judgment, item-rest correlations, and principal component analysis (PCA) followed by confirmatory factor analyses (CFA).
Exploratory and Dimensional Structure
Factor analyses confirmed that the 30 retained items map cleanly onto the eight original subscales, which in turn load onto two overarching second-order factors:
- Physical Functioning Dimension: Encompasses Body Care and Movement, Ambulation, and Mobility. Factor loadings for these domains onto the secondary physical construct routinely exceed $0.70$.
- Psychosocial Functioning Dimension: Encompasses Social Interaction, Emotional Behavior, Alertness Behavior, and Communication. Factor loadings onto the secondary psychosocial construct range from $0.58$ to $0.76$.
- Household Management: Functions as a hybrid domain that loads across both physical and psychosocial constructs, reflecting its mixed demand on motor ability and executive planning.
Confirmatory Factor Models and Goodness-of-Fit
Subsequent structural equation modeling across international validation cohorts has confirmed this hierarchically structured two-factor model. Modern confirmatory factor analytic criteria reflect adequate goodness-of-fit indices: Root Mean Square Error of Approximation (RMSEA) $\approx 0.052 – 0.064$, Comparative Fit Index (CFI) $ge 0.92$, and Tucker-Lewis Index (TLI) $ge 0.90$. Item-to-total correlations for all 30 individual items exceed the conventional $0.35$ threshold, confirming satisfactory construct homogeneity.
10. Instrument / Measurement Tool
- Type of Test: Patient-Reported Outcome Measure (PROM) / Behavioral Health Status Questionnaire.
- Format: Paper-and-pencil questionnaire, structured interview, or proxy-assisted report.
- Target Population: Adult and elderly individuals recovering from ischemic or hemorrhagic stroke (CVA).
- Total Item Count: 30 items.
- Subscale Breakdown:
- Body Care and Movement (BCM): 6 items
- Social Interaction (SI): 6 items
- Mobility (M): 3 items
- Emotional Behavior (EB): 3 items
- Household Management (HM): 4 items
- Alertness Behavior (AB): 3 items
- Ambulation (A): 3 items
- Communication (C): 2 items
- Response Options: Dichotomous format:
0= No / Does not apply to me1= Yes / Applies to me today due to my health
- Administration Time: Approximately 10 to 15 minutes (significantly less than the 30–45 minutes required for the full 136-item SIP).
- Scoring and Transformation Procedures:
- Unweighted Scoring (Standard Approach): Items checked affirmative (1) are summed within each subscale or globally. Global raw scores range from 0 to 30.
- Percentage Transformation: Total raw scores are commonly converted to a 0–100 scale using the formula:
$$\text{Score} = \left(\frac{\text{Sum of endorsed items}}{30}\right) \times 100$$ - Interpretation: 0 indicates no reported functional limitation or sickness impact; 100 indicates maximum sickness impact and complete functional dependency across all assessed areas.
11. Permissions & Fee and Test Year
The Stroke-Adapted Sickness Impact Profile was constructed and published in 1997. While the original parent instrument, the Sickness Impact Profile (SIP, 1981), was copyrighted by Johns Hopkins University, the adaptation (SA-SIP30) was developed by Annemieke van Straten, Rob de Haan, and associates as an open academic modification for clinical research.
The instrument is widely available in the academic literature for non-commercial clinical, academic, and research applications without individual licensing fees. However, institutional investigators planning large-scale multi-site pharmaceutical clinical trials or proprietary software implementations must verify institutional terms with the original authors or relevant journal copyright administrators (American Heart Association / Stroke). In all cases, proper citation of the primary index publication (van Straten et al., 1997) is mandatory.
12. References
- Bergner, M., Bobbitt, R. A., Carter, W. B., & Gilson, B. S. (1981). The Sickness Impact Profile: Development and final revision of a health status measure. Medical Care, 19(8), 787–805. https://doi.org/10.1097/00005650-198108000-00001
- de Haan, R. J., Limburg, M., Van der Meulen, J. H., Jacobs, H. M., & Aaronson, N. K. (1995). Quality of life after stroke: Impact of stroke type and lesion location. Stroke, 26(3), 402–408. https://doi.org/10.1161/01.str.26.3.402
- Post, M. W. M., de Haan, R. J., & van Zandvoort, M. M. (2001). Validity and responsiveness of the Stroke-Adapted Sickness Impact Profile (SA-SIP30). Clinical Rehabilitation, 15(5), 512–520. https://doi.org/10.1191/026921501680425225
- van Straten, A., de Haan, R. J., Limburg, M., Schuling, C. A., Bossuyt, P. M., & van den Bos, G. A. (1997). A stroke-adapted version of the Sickness Impact Profile (SA-SIP30). Stroke, 28(11), 2155–2160. https://doi.org/10.1161/01.str.28.11.2155
- van Straten, A., van der Meulen, J. H., van den Bos, G. A., & de Haan, R. J. (2000). Length of hospital stay and functional recovery in stroke patients. Journal of Clinical Epidemiology, 53(5), 453–459. https://doi.org/10.1016/s0895-4356(99)00192-3