Research from the Model Spinal Cord Injury Systems: findings from the current 5-year grant cycle

Linking Individual Data From the Spinal Cord Injury Model Systems Center and Local Trauma Registry: Development and Validation of Probabilistic Matching Algorithm

BACKGROUND

Linking records from the National Spinal Cord Injury Model Systems (SCIMS) database to the National Trauma Data Bank (NTDB) provides a unique opportunity to study early variables in predicting long-term outcomes after traumatic spinal cord injury (SCI). The public use data sets of SCIMS and NTDB are stripped of protected health information, including dates and zip code.

OBJECTIVES

To develop and validate a probabilistic algorithm linking data from an SCIMS center and its affiliated trauma registry.

METHOD

Data on SCI admissions 2011-2018 were retrieved from an SCIMS center (n = 302) and trauma registry (n = 723), of which 202 records had the same medical record number. The SCIMS records were divided equally into two data sets for algorithm development and validation, respectively. We used a two-step approach: blocking and weight generation for linking variables (race, insurance, height, and weight).

RESULTS

In the development set, 257 SCIMS-trauma pairs shared the same sex, age, and injury year across 129 clusters, of which 91 records were true-match. The probabilistic algorithm identified 65 of the 91 true-match records (sensitivity, 71.4%) with a positive predictive value (PPV) of 80.2%. The algorithm was validated over 282 SCIMS-trauma pairs across 127 clusters and had a sensitivity of 73.7% and PPV of 81.1%. Post hoc analysis shows the addition of injury date and zip code improved the specificity from 57.9% to 94.7%.

CONCLUSION

We demonstrate the feasibility of probabilistic linkage between SCIMS and trauma records, which needs further refinement and validation. Gaining access to injury date and zip code would improve record linkage significantly.

Spinal Cord Injury Model Systems: Review of Program and National Database From 1970 to 2015

The Spinal Cord Injury Model Systems (SCIMS) centers have provided continuous, comprehensive multidisciplinary care for persons with spinal cord injury (SCI) in the United States since their inception in 1970. In addition, the research conducted and the analysis of data collected at these centers facilitate advances in the care and the overall quality of life for people with SCI. Over the past 45 years, the SCIMS program and National Spinal Cord Injury Database (NSCID) have undergone major revisions, which must be recognized in the planning, conduct, and interpretation of SCIMS research to prevent misinterpretation of findings. Therefore, we provide herein a brief review of the SCIMS program and the associated NSCID throughout its history, emphasizing changes and accomplishments within the past 15 years, to facilitate a better understanding and interpretation of the data presented in SCIMS research publications, including the articles published in this special issue of the Archives.

Differences between manufacturers in reported power wheelchair repairs and adverse consequences among people with spinal cord injury

OBJECTIVE

To compare the frequency of power wheelchair (PWC) repairs and consequences experienced over a 6-month period by individuals with spinal cord injury (SCI) who use a PWC ≥40h/wk, based on manufacturer, seating functions, Healthcare Common Procedure Coding System (HCPCS) group, and model, and over time.

DESIGN

Convenience observational sample survey.

SETTING

Spinal Cord Injury Model System centers.

PARTICIPANTS

Individuals with SCI (N=945) who use a PWC ≥40h/wk.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Number of required wheelchair repairs and resulting consequences (ie, being stranded, missing work/school, or missing a medical appointment).

RESULTS

Rates of required repairs (47.6%-63.3%) and consequences (26.7%-40.7%) were high across manufacturers. Differences between manufacturers were found among PWCs without seating functions (P<.001-.008) and among group 2 wheelchairs (P=.007). Across the 10 most prescribed wheelchairs in this study, 54.5% to 73.9% of users required 1 or more repairs over a 6-month period. Increases in the number of repairs were also found for several PWC manufacturers with time. Differences were found in participant age, working status, years since injury, and presence of seating functions between manufacturers.

CONCLUSIONS

The differences found in the number of repairs reported by survey respondents based on PWC manufacturer and the increases in repairs over time require further evaluation.

Team size in spinal cord injury inpatient rehabilitation and patient participation in therapy sessions: the SCIRehab project

CONTEXT/OBJECTIVE

Rehabilitation teams generally are described as consisting of a single representative of 6-8 disciplines, but research suggests that the number of individuals involved may be much larger. This study aimed to determine the size of teams in spinal cord injury (SCI) rehabilitation, and the effect of team size on patients' active participation in their treatment sessions.

DESIGN

Prospective observational study.

SETTING

Six SCI rehabilitation centers.

PARTICIPANTS

A total of 1376 patients with traumatic SCI admitted for first rehabilitation.

INTERVENTIONS

Not applicable.

OUTCOME MEASURES

Number of treatment sessions, by discipline and overall clinician rating of active participation of the patient; Treatment Concentration Index (TCI) calculated as Σp(k)(2) (where p refers to the proportion of treatment sessions delivered by team member k).

RESULTS

The average patient was treated by 39.3 different clinicians. The numbers were especially high for physical therapy (mean: 8.8), occupational therapy (7.2), and nursing (16.1). TCI was 0.08 overall; it varied by discipline. TCI was negatively correlated with length of stay, except for psychology. Participation ratings were minimally affected by the number of sessions the patient and the therapist had worked together.

CONCLUSIONS

In SCI rehabilitation, teams are at least as large as suggested by previous research. However, this may not mean lack of familiarity of patient and therapist with one another, or alternatively, the possibly weak therapeutic alliance does not affect the patients' active participation in their sessions. Further research is needed to determine whether there are negative effects on rehabilitation outcomes.

Spinal cord injury-functional index: item banks to measure physical functioning in individuals with spinal cord injury

OBJECTIVES

To develop a comprehensive set of patient-reported items to assess multiple aspects of physical functioning relevant to the lives of people with spinal cord injury (SCI), and to evaluate the underlying structure of physical functioning.

DESIGN

Cross-sectional.

SETTING

Inpatient and community.

PARTICIPANTS

Item pools of physical functioning were developed, refined, and field tested in a large sample of individuals (N=855) with traumatic SCI stratified by diagnosis, severity, and time since injury.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

Spinal Cord Injury-Functional Index (SCI-FI) measurement system.

RESULTS

Confirmatory factor analysis (CFA) indicated that a 5-factor model, including basic mobility, ambulation, wheelchair mobility, self-care, and fine motor function, had the best model fit and was most closely aligned conceptually with feedback received from individuals with SCI and SCI clinicians. When just the items making up basic mobility were tested in CFA, the fit statistics indicated strong support for a unidimensional model. Similar results were demonstrated for each of the other 4 factors, indicating unidimensional models.

CONCLUSIONS

Though unidimensional or 2-factor (mobility and upper extremity) models of physical functioning make up outcomes measures in the general population, the underlying structure of physical function in SCI is more complex. A 5-factor solution allows for comprehensive assessment of key domain areas of physical functioning. These results informed the structure and development of the SCI-FI measurement system of physical functioning.

Current research outcomes from the spinal cord injury model systems

This article serves as an introduction to this issue of the Archives of Physical Medicine and Rehabilitation that is devoted to current research findings of the Spinal Cord Injury Model Systems (SCIMS) program. The SCIMS program began in 1970, with funding from the National Institute on Disability and Rehabilitation Research in the U.S. Department of Education, to demonstrate a comprehensive care system for spinal cord injury (SCI) and also to conduct research to improve the health and quality of life of persons with SCI. Over the last 20 years, similar collaborative efforts for the dissemination of SCIMS research outcomes have produced conference proceedings in 1990, a book in 1995, and dedicated journal issues in 1999 and 2004. The collection of 24 articles in this issue shows the depth and breadth of work being carried out by the SCIMS investigators, from descriptive epidemiology to a randomized controlled trial, from neurologic recovery to community reintegration, and from health services utilization to assistive technology for mobility. Herein, we provide a brief overview of the SCIMS program, highlight the research initiatives currently underway, and describe the important findings of the original research articles contained in this issue.

Conversion in ASIA impairment scale during the first year after traumatic spinal cord injury

The neurological severity of a spinal cord injury (SCI) is commonly classified according to the American Spinal Injury Association (ASIA) Impairment Scale (AIS). The aim of this study was to assess the course of the AIS following SCI, and to discern the nature of any changes in the classification that occur. Assessments were performed in a European cohort of SCI patients within 2 weeks and at 1, 3, 6, and 12 months after the initial injury. Overall, about 70% of the patients initially diagnosed as AIS A did not convert, as did 90% of the AIS D patients. When only evaluating patients with complete datasets, 68% did not convert, while the AIS category improved in 30% of patients and deteriorated in 2%. A change in the last sacral segments (40%), motor improvement (31%), sensory improvement (19%), and a change in the neurological level of the SCI (10%) contributed to or accompanied the AIS conversion. When the AIS remained unchanged between successive assessment points, there was no change in the number of muscles graded three or more (NMG3(+)) in 73% of the transitions. An improvement in AIS was associated with a gain in NMG3(+) in 49% of the transitions, while an aggravation in AIS was accompanied by a loss in NMG3(+) in 10% of the transitions. These results, documenting a substantial amount of spontaneous AIS conversions, should be taken into consideration when designing clinical trials to assess the effects of potential new treatments for SCI.

Wheelchair repairs, breakdown, and adverse consequences for people with traumatic spinal cord injury

McClure LA, Boninger ML, Oyster ML, Williams S, Houlihan B, Lieberman JA, Cooper RA. Wheelchair repairs, breakdown, and adverse consequences for people with traumatic spinal cord injury.

OBJECTIVES

To investigate the frequency of repairs that occurred in a 6-month period and the consequences of breakdowns on wheelchair users living with spinal cord injuries (SCIs), and to determine whether certain wheelchair and subject characteristics are associated with an increased number of repairs and adverse consequences.

DESIGN

Convenience sample survey.

SETTING

Sixteen Model Spinal Cord Injury Systems Centers that are part of the national database funded through the Department of Education, National Institute on Disability and Rehabilitation Research.

PARTICIPANTS

People with SCI who use a wheelchair for more than 40h/wk (N=2213).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

The frequency of wheelchair repairs and occurrence of adverse consequences caused by a wheelchair breakdown in a 6-month period.

RESULTS

Within a 6-month period, 44.8% of full-time wheelchair users completed a repair, and 8.7% had an adverse consequence occur. People who use power wheelchairs required significantly more repairs (P<.001), and adverse consequences occurred more frequently (P<.001) compared with manual wheelchair users. The presence of power seat functions, and a person's occupational status or sex did not influence the number of repairs or adverse consequences.

CONCLUSIONS

Frequent repairs and breakdown can negatively impact a person's life by decreasing community participation and threatening health and safety. Mandatory compliance with the American National Standards Institute and the Rehabilitation Engineering and Assistive Technology Society of North America standards, changes in insurance reimbursement policy, and patient and clinician education are necessary to reduce the number of repairs and adverse consequences that occur.

Results From a Prospective Acute Inpatient Rehabilitation Database: Clinical Characteristics and Functional Outcomes using the Functional Independence Measure

Introduction: Rehabilitation improves functional outcomes, but there is little data on the profiles and outcomes of patients undergoing inpatient rehabilitation in Singapore. The aims of this paper were to document the clinical characteristics and functional outcomes, using the Functional Independence Measure (FIM), of all patients admitted to an inpatient rehabilitation unit in a tertiary teaching hospital, and to identify and analyse factors significantly associated with better discharge functional scores and higher functional gains. Materials and Methods: In this prospective cohort study over a 4-year period, clinical and functional data for 1502 patients admitted consecutively to the Singapore General Hospital inpatient rehabilitation unit were charted into a custom-designed rehabilitation database. The primary outcome measures were the discharge total FIM scores, FIM gain and FIM efficiency. Multiple linear regression analysis was used to identify independent variables associated with better discharge FIM scores and FIM gain. Results: The mean age was 61.3 ± 15.0 years and 57.2% of the patients were male. Stroke (57.9%) followed by spinal cord injury (9.7%) were the most common diagnoses. The average rehabili-tation length of stay was 21.5 ± 19.0 days. The mean admission total FIM score was 70.3 ± 23.2 and the mean discharge total FIM score was 87.3 ± 23.0, with this gain being highly significant (P <0.001). The mean FIM gain was 17.0 ± 13.4 and FIM efficiency was 0.95 ± 0.90 points/day. Factors associated with better functional outcomes were higher admission motor and cognitive FIM scores, male gender, a longer rehabilitation length of stay and the use of acupuncture. Factors associated with poorer functional outcomes were older age, clinical deconditioning, ischaemic heart disease, depression, pressure sores and the presence of a domestic worker as a caregiver. Conclusions: The FIM is an easy-to-use, standardised and robust general measure of functional disability. Multiple demographic, clinical and socio-cultural variables are associated with the primary functional outcomes and should be taken into account in rehabilitation and discharge planning. Nevertheless, rehabilitation improves functional outcomes across a wide range of diagnoses. Further research should be aimed at evaluating long-term disability post-discharge from inpatient rehabilitation and translating these findings into improving rehabili-tation and healthcare resource utilisation. Key words: Database, Functional Independence Measure, Functional outcomes, Rehabilitation,