Disability Outcomes Following Inpatient Rehabilitation for Stroke

Transcription

1 - Disability Outcomes Following Inpatient Rehabilitation for Stroke The Uniform Data System for Medical Rehabilitation and the Functional Independence kleasure have been utilized to evaluate outcomes of patients undetgoing initial comprehensive inpatient medical rehabilitation for stroke. The Functional Independence Measure total, domain, subscale, and item scores were wed to monitor. patients during and following rehabilitation. The benchmark function values and times from stroke onset were reported, and the functional areas of physical therapy participation were noted. It is expected that these benchmarks may serve as a baseline for future study of the extent and rate offunctional return following stroke and for strengthening the scientt$c bask of rehabilitation practice:, leading to improved effectiveness and eficiency of rehabilitation therapy. [Hamilton BB, Granger CV. Disability outcomes following inpatient rehabilitation for stroke. Phys Ther 199g 74: ] Byron B Hamilton Carl V Granger Key Words: Disability, Functional assessment, Functional Independence Measure, Outcomes, Rehabilitation. Background and Purpose A principal objective of comprehensive inpatient medical rehabilitation is to increase patient function at the person level of biological organization. Functions at this level include self-care and mobility. In the World Health Organization Classification of Impairments, Disabilities, and Handicaps, this level refers to the area of disability.' An instrument designed and broadly used to assess function at this level and in this setting is the Functional Independence Measure (FIM); a, higher FIM score means a higher level of independence.z4 The functiorlal outcome of a patient following rehabilitation is usually as- sessed by documenting discharge or follow-up level of function or by determining change in function (ie, by subtracting the admission level of function from the discharge or follow-up level). This gain in function is likely attributable to a number of factors, among which are the patient's capacity to regain function (including learning ability), therapeutic intervention, and time. The contribution of these or other factors to functional outcome, however, is yet to be elucidated. Documenting gains in patient function within specific impairment groups using a uniform functional assessment instrument allows rehabilitation facili- BB Hamilton, MD, PhD, is Clinical Associate Professor and Director for Research, Center for Functional Assessment Research, Department of Rehabilitation Medicine, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, 232 Parker Hall, SUNY South Campus, Buhlo, bn (USA). Address all correspondence to Dr Hamilton. CV Granger, MD, is Professor and Director, Center for Functional Assessment Research, Department of Rehabilitation Medicine, School of Medicine and Biomedical Sciences, State University of New York at Buffalo. ties or clinicians to compare their findings with those of others and to assess program or practice effectiveness. Further, functional gain efficiency, that is, gain divided by length of stay (in days) or by therapy units, can also be compared. For example, a similar gain in function achieved in a shorter time or with fewer therapy units would be a more efficient outcome when compared with standard practice. Uniform Data System for Medical Rehabllltation The Uniform Data System for Medical Rehabilitation (UDSMR) was developed from 1983 to 1987 by a joint task force of the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation in collaboration with 11 other rehabilitation organizations, including the American Physical Therapy Association (APTA). The purpose was to satisfy a long-standing need to uniformly define, measure, Physical Therapy /Volume 74, Number 5/May / 125

2 Table 1. Functional Independence Measure Levels of Function and Their Scoref Independent. Another person is not required for the activity (NO HELPER) 7-Complete Independence. All of the tasks described as making up the activity are typically performed safely without modification, assistive devices, or aids, and within a reasonable amount of time 6-Modlfled Independence. Activity requires any one or more than one of the following: an assistive device, more than a reasonable amount of time, safety (risk) considerations Dependent. Another person is required for either supervision or physical or other assistance in order for the activity to be performed, or it is not performed (REQUIRES HELPER) Modlfled dependence. The subject expends half (50%) or more of the effort. The levels of assistance required are: 5-Supewlslon or setup. Subject requires no more help than standby, cuing, or coaxing, without contact if motor activifyor without significant promptingldirection if cognitive activity, or helper sets up needed items or applies orthoses 4--Mlnlmal asslstance. Subject, with only touching contact if motor activity or some promptingldirection if cognitive activity, expends 75% or more of the effort %Moderate asslstance. Subject requires more help and expends half (50%) or more (up to 75%) of the effort Complete dependence. Subject expends less than half (less than 50%) of the effort; maximal or total assistance is required, or the activity is not performed; the levels of assistance required are: 2-Maxlmal asslstance. Subject expends less than 50% of the effort, but at least 25% 1-Total asslstance. Subject expends less than 25% of the effort "Scale levels are slightly modified "generic" descriptors. See Guide for [Jse of tbe hejnifon Data Set for Medical Rehabilitation (Version 3.1)6 for descriptors of individual item scale levels. document, and report the severity of patient disability and the outcomes of rehabilitation. The UDSMR is a not-forprofit rehabilitation information service developed and managed under the auspices of the Center for Functional Assessment Research, Department of Rehabilitation Medicine, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, with counsel from the UDSMR National Advisory Committee, including representation of the AFTA. Functional Independence Measure The Functional Independence Measure (FIM) is an 18-item, seven-level ordinal scale that is used to assess the patient's needs for assistance or devices in order to accomplish daily activities in self-care, sphincter control, transfer, locomotion, communication, and social cognition.5 The generic FIM scale levels and scoring are described in Table 1. For each of the 18 FIM items, specific scaling descriptors are used; these descriptors are described in the UDSMR Guide.5 The FIM items, subscales, domains, and total scale are listed in Table 2. The FIM has been found to be reliable,3.6.7 valid,'-14 and sensitive to change3<'5 as a measure of disability. Thus, the FIM can be combined with other data elements to investigate and understand how to improve the medical rehabilitation process and outcomes. The purposes of this article are to examine inpatient rehabilitation functional outcome following stroke, as measured by the FIM and reported by the UDSMR, and to note FIM item functional outcomes of interest to physical therapists. Although the data reported here can entertain numerous questions, some specific questions addressed in this article are: What are the demographic characteristics of this large national sample of patients who have had a stroke? How long after stroke onset do patients come to rehabilitation? At what level of disability are these individuals when they come to rehabilitation? How much gain in function is achieved in which specific areas? Which of these gains are of most interest to physical therapists? How long does it take to achieve these gains and with what efficiency? Where do patients go at rehabilitation discharge, and how long does it take fmm stroke onset to reach these discharge destinations? Where are patients at 5 months following stroke, and what is the level of function at that time? This article provides detailed analysis of functional assessment for a very large, geographically dispersed sample of patients undergoing initial medical rehabilitation for stroke in the United States. Functional Independence Measure item scores and follow-up scores have not been published previously for stroke. Functional outcomes for patients with stroke based on age and site of body impaired using the UDSMR patient database and FIM assessment have been reported for subscales and total FIM scores.16 Other characteristics and outcomes of patients with stroke utilizing UDSMRFIM data in 1990 and 1991 have also been rep0rted.17~~~ Data Sources The answers to the questions posed are based on a recent special stroke report of the UDSMR (unpublished report, 1993), and the functional areas of interest to physical therapists are Physical Therapy/Volume 74, Number Sway 1994

3 - Table 2. Functional Independence Measure (FIM) Item Scores for Patients With Stroke (N=27,034) at Admission and Discharge" item Name Admission Discharge Change A-F G H I-K L M A-M N 0 P-R P Q R N-R A-R Self-care Eating Grooming Bathing Dressing upper body Dressing lower body Toileting Sphincter control Bladder Bowel Transfers Bed Toilet Tub Locomotion Walking/wheelchair Stair climbing Motor subtotal Communication Comprehension Expression Social cognition Social interaction Problem solving Memory Cognitive subtotal Total FIM score a"total FIM score" refers to the sum of all 18 items (items A-R). "Motor subtotal" is the sum of items A-M, and "cognitive subtotal" is the sum of items N-R. The remaining subscales (eg, selfcare, sphincter control, and so on) represent the sum of the subsumed items. "Change" is the gain in FIM from admission to discharge. "Item average" is calculated by dividing the total, domain, or subscale score by the number of items making up the scale. For example, "total FIM score item average" is calculated by dividing the total FIM score by 18 to yield an average score for all items. *The unpublished mail survey was conducted in early 1991 by Deborah Wilkerson, Director, Program Evaluation and Outcome Studies, National Rehabilitation Hospital, Washington, DC. These findings wlere presented at the SUNY-Buffalo Conference on Rehabilitation Medicine (Continuous Interdisciplinary Quality Improvement); July 1C11, 1991; Buffalo, NY. based on a survey of UDSMR subscribers. The UDSMR patient database was generated from a minimum data set of demographic, diagnostic, functional, and rehabilitation resource use items.5 Data were collected by subscribing UDSMR facilities and submitted to the UDSMR Data Management Service each calendar quarter. The UDSMR checked and corrected incoming data for errors and omissions and reported aggregated data back to each facility 1 month later. Reports compared facility data with data from similar facilities in the same geographic region and with national aggregate data. Before their data were aggregated into the region and national databases, each facility must have demonstrated that its clinicians were reliable in functional assessment using the FIM. The process for achieving and demonstrating this competence consisted of in-service training and testing using a standardized training guide,5 videotapes, and a written clinical narrative "credentialing" test processed by the UDSMR. A clinician was reliability-credentialed if he or she achieved 80% correct agreement on the 54 FIM items of the test, using three test cases. The data reported here were based on calendar year 1992 UDSMR data for patients with stroke (UDSMR impairment groups 01, 01.1, and 01.2) admitted and discharged for first definitive rehabilitation (unpublished report, 1993). Functional Independence Measure Items Assessed by Physical Therapists To better understand which clinical disciplines were assessing which FIM items, a survey of UDSMR subscribers was conducted in 1991.* Preliminary findings of this survey have been published in abstract format.l9 Of the disciplines represented by the 114 facilities responding, physical therapists most frequently assessed bed/ chair transfer (84%), locomotion (97%), and stair climbing (98%). Physical therapists were the second most frequent assessors of toilet transfer (38%) and tub transfer (29%), Physical Therapy /Volume 74, Number 5/May 1994

4 - Table 3. Functional Independence Measure (FIM) Item Scores for Patients With Stroke (n=5,190) at Admission, Discharge, and Follow-upa Item Name Admlsslon Dlscharge Change Follow-up Change A-F G H I-K L M A-M N 0 P-R P Q R N-R A-R Self-care Eating Grooming Bathing Dressing upper body Dressing lower body Toileting Sphincter control Bladder Bowel Transfers Bed Toilet Tub Locomotion Walkinglwheelchair Stair climbing Motor subtotal Communication Comprehension Expression Social cognition Social interaction Problem solving Memory Cognitive subtotal Total FIM score "First "Change" column refers to FIM gain from admission to discharge; second "Change" column refers to further gain from discharge to follow-up. after occupational therapists (43% and K, L, M in Tab. 2) would be of partic- 60%, respectively); physical therapists ular interest to physical therapists and were not significantly involved in are examined later. assessment of any other FIM items. It is assumed that if physical therapists Follo W-up assessed function in a given area, they also provided therapy in the same At 105 days, on average, after disarea. These five FIM items (items I, J, charge from rehabilitation, 5,190 pa- tients with stroke were contacted for follow-up by UDSMR-subscribing facilities by telephone (91%), in person (4%), by mail (2%), or by unspecified means (2%). The respondents were the former patient (39%), family (46%), other (10%): and unspecified (5%). The functional scores for this patient sample are reported in Table 3. Other Definitions "Right stroke" means right-side hemiparesis resulting from an infarct or hemorrhage in the left hemisphere of the brain, and "left stroke" means left-side hemiparesis due to an infarct or hemorrhage in the right hemisphere of the brain. "Item average score" refers to an FIM subscale, domain, or total score that is the average for all constituent items making up the category. For example, the subscale category "self-care" consists of six FIM items, with each item score on admission given in parentheses: eating (4.4), grooming (4.0), bathing (2.9), dressing upper body (3.4), dressing lower body (2.9), and toileting (3.0) The item average score for the self-care category is the average of these six item scores; that is, 3.4. Results Facility and Patient Sample During calendar year 1992, 256 reliability-credentialed comprehensive medical rehabilitation inpatient facilities from 44 states with a total of 11,397 beds reported 85,157 first-time rehabilitation discharges to UDSMR. Approximately 60% of the patients were discharged from freestanding rehabilitation (FR) hospitals, and about 40% were from acute care hospital rehabilitation (AHR) units. There were 94 FR hospitals, with 6,796 beds (72 beds average), and 162 AHR units, with 4,601 beds (28 beds average). Patients with stroke numbered 27,034, or 32% of the total. Patients with left- and right-side stroke each represented 44% of the total; 3% of these patients had bilateral paresis, 4% had no paresis, and 6% had unspecified forms of stroke (Tab. 4). 128 / 497 Physical Therapy /Volume 74, Number 5Nay 1994

5 - Table 4. Summary of Characteristics for Patients With Stroke Reported by the Uniform Data System for Medical Rehabilitation for Calendar Year 199P Characterlstlc Impairme!nt group (%) Left hemiparesis Right hemiparesis Bilateral No paresis Other Age (Y) - X2SD 044 (%) 4564 (%) (%) 75+ (%) Female ('A) Racelethnicity (%) White Black Asian Hispanic Other Marital status (%) Single Married Widowed Separated Divorced Living with at onset (%) Alone Familylrelatives Friends; Attendant Other Unspecified FIM score (X-cSD) Admission Discharge Gain Length of stay (net days) Length of stay efficiency (mean FIM gainld) Onset to rehabilitation admission (d) Onset to rehabilitation discharge (d) Value ""Length of stay (net days)" refers to total number of days from rehabilitation admission to discharge minus nurnber of days transferred off the rehabilitation service for acute care management of complications or other reasons. If interruption of service exceeded 30 days, the patient was considered to have been discharged to acute care and no Further rehabilitation data were reported for the initial admission. "Length of stay eficiency" is calculated by subtracting admission Functional Independence Measure (FIM) score from discharge FIM score, then dividing that difference by length of stay in days. "Onset" refers to the number of days from stroke onset to admission to or discharge from rehabilitation. Patient Demographics The demographic characteristics of the patient sample are also presented in Table 4. The average age was 71 years (SD= 12), and 53% of the patients were female. Race or ethnicity was predominately white (81%) and black (12%), marital status was predominately married (53%) and widowed (32%), and "living with whom" at stroke onset was predominately family/relatives (67%) and alone (28%). Total Patlent Functlon, Efficiency, and Key Event Times The patient function level measured by FIM total score was 62.0 (SD=21.8) on admission and 85.9 (SD=25.5) at discharge, and the gain was 23.9 (SD=14.4) (Tab. 4). The medians were 63 on admission and 91 at discharge. Tests of difference significance have not been reported in UDSMR reports. With such large samples, however, it is not surprising to observe that standard errors of the mean (SEM) were very small. Total FIM SEMs were 0.13 on admission and 0.16 at discharge, and the gain was A total FIM gain of 23.9 with a gain SEM of 0.09 would be a highly significant change score. Alternatively, if one took a random sample of 185 of these patients and applied this sample size to the standard deviation of the large sample (which would have about the same standard deviation as 185 patients), the total FIM 95% confidence intervals would be 59 to 65 on admission and 82 to 90 at discharge, significantly different intervals. Mean length of stay (LOS) was 28 days (SD= 17.1) (Tab. 4). Average length of stay efficiency (that is, average FIM gain + average LOS days) was 0.85 FIM units gained per day. Finally, days from onset of stroke to rehabilitation admission averaged 20 days, and days from onset to definitive discharge from rehabilitation was 48 days. Physical Therapy /Volume 74, Number 5/May 1994

6 Functional lndependence Measure Total, Domain, and Subscale Scores Expressed as "Item Average Scores" In addition to total FIM scores, domain scores (motor and cognitive) and subscale scores (self-care, sphincter control, transfers, locomotion, communication, and social cognition) are of interest. Table 2 identifies admission, discharge, and gain scores in detail, based on the same large national sample described in Table 4. Total Functional lndependence Measure function. The patients with stroke had an item average score of 3.4 units on admission and 4.8 units at discharge, with an item average gain of 1.3 units (rounded) (Tab. 2). Presumably, this gain was highly significant, because the item averages were derived from the total FIM scores reported earlier. DOmaln function. On admission, the patients had a motor domain item average score of 3.2 units and a cognitive score of 4.2 units; the motor score was 1.0 unit lower (difference significance not reported) (Tab. 2). At discharge, the motor average was 4.7 units and the cognitive average was 5.0, a difference only 0.3 units lower. The motor gain from admission to discharge was 1.5, and the cognitive gain was 0.8; the motor gain was nearly double the cognitive gain. Subscale function. On admission, of the six FIM subscales, the lowest level of function was locomotion (walking/ wheelchair and stair-climbing items), averaging 2.0 units (that is, a level of maximal assistance) (Tab. 2). The highest subscale score was for communication (comprehension and expression items), with an average of 4.5 units (that is, between a level of minimal assistance and supervision). The remaining four subscale scores were 2.9 for transfers, 3.4 for self-care, 3.9 for sphincter control, and 4.0 for social cognition, that is, a narrow range of from moderate to minimal assistance. At discharge, the lowest level of function was still locomotion (3.8), and the highest levels were communication (5.2) and sphincter control (5.2). The remaining three subscales were closely clustered at discharge: transfers (4.5), social cognition (4.8), and self-care (4.9). The largest gains were seen in locomotion (1.8), transfers (l.6), and self-care (1.5), and the lowest gains occurred in communication (0.7) and social cognition (0.8). The locomotion and transfer gains are of interest to physical therapists. lndlvldual Functlonal Independence Measure item function. On admission, individual FIM item scores ranged from 1.6 to 4.6 (Tab. 2). Of all 18 items, the lowest 3 items (most difficult for patients) were stair climbing (l.6), walkinghheelchair (2.4), and tub transfer (2.4), all in the range of maximal assistance. The stair climbing and walkinghheelchair items are of particular clinical interest to physical therapists. The items with the highest level of function (easiest) on admission were comprehension (4.6), social interaction (4.5), expression (4.4), and eating (4.4), all in the range requiring supervision to minimal assistance of another person. The remaining 11 FIM items fell in a narrow range between 2.9 and 4.0, between moderate and minimal assistance. At discharge, the FIM item scores ranged from 3.3 to 5.5 (Tab. 2). Of all 18 items, the lowest 4 items were stair climbing (3.3)) tub transfer (4.1), walkinghheelchair (4.4)) and bathing (4.4); all except stair climbing were just above minimal assistance. All except 1 of these items (bathing) were also most difficult on admission. The 5 items with the highest scores at discharge were closely clustered: eating (5.5), grooming (5.4), bowel (5.3), comprehension (5.3), and social interaction (5.3), all in the range requiring supervision to modified independence. Three of these itemscomprehension, social interaction, and eating-were also the easiest on admission. The remaining 9 FIM items fell in the narrow range of 4.5 to 5.1, just below or at the level of supervision. The FIM item gain scores ranged from 0.7 to 2.0 (Tab. 2). Of all 18 items, the largest gains were made in walkinghheelchair (2.0), stair climbing (1.7), and tub transfer (1.7). These items were also the most difficult on admission, and where the most gain could be made. Close behind were 5 items with identical (1.6) gain scores: dressing upper body, dressing lower body, toileting, bed transfer, and toilet transfer, constituting the upper middle gain range. The smallest gains were made in the following narrowly clustered items: comprehension (O.7), expression (O.7), social interaction (0.8), problem solving (0.8), and memory (0.8). These were all the cognitive domain items and, although among the easiest on admission, they had about half the gain of the other 4 easy items: eating (1.2)) bowel (1.3), bladder (1.4), and grooming (1.4). These last 4 items and bathing (1.5) all fell in the narrow lower middle gain range of 1.2 to 1.5. Follo w-up The 5,190 patients with stroke who were followed an average of 105 days after initial rehabilitation discharge had slightly different functional characteristics than all 27,034 patients admitted to rehabilitation. Although the admission total FIM scores were similar for both groups (total Sample=62.0, subsample=62.7), the discharge scores were different (total sample=85.9, subsample=89.3); the patients who were followed had a higher level of function than those who were not followed (compare Tabs. 2 and 3). This finding could occur if lower-functioning patients had died or were more difficult to contact and engage for a follow-up interview. The follow-up FIM total score was 97.6 units, or an average of 5.4 units for all FIM items, a gain of 0.5 units (10%) over the discharge score (Tab. 3) (note: 1-decimal point rounding introduces some apparent discrepancies; change scores are accurate). The motor domain score increased 0.4 units (8%), and the cognitive domain score increased 0.7 units (14%), or Physical 'I rherapy/volume 74, Number 5/May 1994

7 Table 5. Living Setting and Living With at Discharge and Follow-upa Dls- Followcharge up N 27,165 5,539 Living setting (%) Home Board and care 2 2 Transitional living 0 0 Intermediate care 2 2 Skilled nursing Acute unit--own facility 2 1 Acute careother facility 5 1 Chronic care hospital 0 0 Rehabilitation facility 1 0 Other 1 0 Died 0 6 Unspecified 0 0 Living wilh (%) Alone Family/relatives Friends 1 1 Attendant 4 3 Other Unspecified 1 6 Time since onset (d) Time since discharge (d) 105 ""Living setting" refers to where former patients were living at discharge and at followup; "living with" refers to with whom the former patient was living at discharge and at follow-up. almost double the motor domain gains, between discharge and follow-up. Subscalr: average scores increased most for social cognition (0.8 units [16%]) and communication (0.6 [11%]) and least for self-care (0.3 [6%]) and transfers (0.4 [8%]). Intermediate gains were made for sphincter control and locomotion (0.5 each 19%-12761). The FIM items gained 0.0 to 0.9 units from discharge to follow-up (Tab. 3) The largest gains were made in memory (0.9 [19%]), problem solving (0.8 [17%]), and walkinghheelchair (0.7 [15%]) by 105 days after rehabilitation discharge. No gain was made in dressing upper body, and grooming (0.1) and bathing and stair climbing (0.2 each) had very small gains. The remaining 12 items had intermediate gains ( units). Living seitlng and Iivlng with at discharge and follow-up. At rehabilitation discharge, the patients were discharged mostly to home (74%), skilled or intermediate care nursing facilities (15%), or acute care facilities (7%) (Tab. 5). The 105-day postdischarge follow-up sample, which was biased in favor of slightly higherfunctioning patients, had a few more at home (77%), fewer in nursing facilities (11%), fewer in acute care facilities (2%), and a new group of patients who had &ed (6%). At discharge, the patients were living with mostly family or relatives (62%), "other" (22%; consisting of those in nursing, acute care, or rehabilitation facilities), or alone (10%). At follow-up, the same percentage were living with family or friends (62%), fewer were living with "other" (15%; accounted for in part by those who had died), and more were living alone (14%). Dlscusslon Uniformity in assessment of patient level of disability and rehabilitation functional outcome strengthens the scientific basis for medical rehabilitation practice. [Jniformity promotes reliability of measurement and likely reflects consensus and common understanding among practitioners in the field. These were the strategic needs perceived by the Task Force to Develop a Uniform Data System for Medical Rehabilitation in The FIM was designed to help achieve these objectives, and thus far it appears to be succeeding. More than half of rehabilitation hospitals (56%) and units (52%) responding to the American Hospital Association Section for Rehabilitation Hospitals and Programs Survey for 1991 indicated they were using the UDSMR and the FIM for program evaluation/functional assessment.20 Over 425 rehabilitation hospitals and units in 48 states subscribe to the UDSMR, and more than 90,000 patient records were added to the UDSMR database in calendar year The kinds of questions a measurement scale may be expected to help answer depend on how the scale is classified: (1) discriminative, (2) predictive, or (3) evaluative. For example, the FIM helps to quantify disability in order to discriminate among classes of subjects with respect to severity of disability, and it helps to predict dscharge to living in the community as contrasted with living in a nursing home. The FIM also predicts the resource cost of maintaining a person with disability at home or in a longterm care facility, if there is no further functional improvement. Further, the FIM is evaluative, permitting the therapist to detect clinically important change when it occurs, and from this evaluate effectiveness and efficiency of the functional recovery process, and to compare one program with another. Therefore, the FIM contributes to answering all three types of questions. The answers to the questions posed in the "Background and Purpose" section may be summarized as follows. From the results reported here for 1992, the patients with stroke were predominately and equally left (44%) and right (44%) hemiparetic; averaged 71 years of age; and were more frequently female (53%), mostly white (81%), often widowed (32%), and often living alone (28%). Patients arrived in comprehensive medical rehabilitation about 3 weeks after stroke onset and were discharged 4 weeks later; total elapsed time from stroke onset to discharge was 7 weeks. Overall, average function for 18 items increased from a level between moderate and minimal assistance on admission (total FIM item average=3.4) to near supervision at discharge (total FIM item average= 4.8). Further gains were made by follow-up 15 weeks later, or 22 weeks after stroke onset, to a level between supervision and modified independence (total FIM item average=5.4). A "nor- Physical Therapy /Volume 74, Number 5Nay 1994

8 mal" person without disability would have an FIM score of 7.0. Thus, approximately 75% of "normal" function as measured by the FIM had returned by 22 weeks poststroke. In contrast to the period from admission to discharge, during which nearly twice the gain was made in motor domain scores compared with cognitive scores, from discharge to follow-up, the opposite was truecognitive gain nearly doubled motor gain. Physical therapists provided service to patients for 5 of the 18 function items monitored: stair climbing, walkingl wheelchair, bed-chair transfer, toilet transfer, and tub transfer. Function in these areas increased from an FIM item average of 2.5 at rehabilitation admission to 4.2 at discharge, and further increased to 4.9 at follow-up, an overall average gain of 2.4 units. This gain represents an increase in function in these areas from a level between maximal and moderate assistance at admission to near supervision at follow-up 22 weeks after stroke onset. This set of observations on therapy participation and functional gain has not been previously reported. The purpose for reporting these "benchmark" functional values and times is to establish a baseline from which to estimate therapy effectiveness and efficiency and to compare innovative therapy interventions in the future. Length of stay function return "efficiency" has been estimated for a large national sample of patients with stroke in the data presented in the "Results" section. Although functional gain and rate of discharge to community settings has remained about the same for patients with stroke since 1990, LOS has decreased 4 days and LOS efficiency has increased from.78 to.85 FIM units gained per day.17j8 The implication of these data is that the same outcomes are being achieved at less resource cost, in terms of rehabilitation days. This improved "cost" efficiency seems desirable, based on findings to date. The concept of rehabilitation "cost" efficiency (that is, average patient FIM gain per day or average FIM gain per dollar charged) has implications beyond estimating institutional resource efficiency. A more fundamental application of the cost efficiency concept is patient FIM gain per hour of therapy, or therapy efficiency. That is, over the course of initial inpatient medical rehabilitation, what was the quantitative relation between FIM units of gain in walkinghheelchair function, stair climbing, and transfers to bed/ chair and the hours of physical therapy devoted to those tasks? Probably any clinician can document this information on a sample of 15 of his or her patients with stroke and compare the results with those of other clinicians or programs. Such an exercise could be very instructive. If the results were significantly different comparing therapist A with therapist B, what could explain the difference? Was it the therapeutic technique? Intensity? Modality? Was it timing (that is, using a different technique at the strategically "right" or "wrong" time)? Was it the patient? Age? Comorbidiry? Different time from impairment onset to rehabilitation admission? Different level of admission FIM score? Was it a combination of these variables? Having a uniform, valid, reliable, and sensitive measure of patient function and careful characterization and quantification of care interventions provides the key elements for this insightful quest. If we can answer these questions in an orderly, rigorous way, we will likely establish a scientific (that is, rational and predictable) basis for patient outcome management. This is where the fundamental efficiency of rehabilitation care can be best understood and managed. Program and institutional effectiveness and efficiency will likely improve when we better understand the scientific basis of our practice. The items of the FIM and most other functional assessment scales used in rehabilitation today are fundamentally ordinal in character.21 Because they are ordinal, there are some limitations on what statistical procedures may be applied in comparisons using these scales. This limitation affects some results reported by the UDSMR. Manual muscle strength testing results may be reported on an ordinal scale (eg, 5, 4, 3, 2, 1, 0), where a score of 5 means more strength than a score of 4 and a score of 2 means more strength than a score of 1, but the difference in strength between 5 and 4 is not necessarily equal to the difference between 2 and 1. The numbers imply equal intervals, but in reality, the levels are probably not equal. On the other hand, muscle strength measured with a dynamometer is reported in equal dyne units, a true interval scale. Ordinal scale measurement comparisons are subject to nonparametric statistical procedures (eg, comparison of rank orders), whereas interval scale measurement comparisons are subject to more powerful or rigorous parametric statistical procedures (eg, standard deviation, t test, or regression). Although FIM items are ordinal, it is not clear whether summed FIM items such as subscale, domain, and total scores are ordinal, quasi-internal, or interval. The position we have taken is that item scores are clearly ordinal and not subject to parametric statistical applications, but summed FIM items, such as total FIM scores, are more interval or quasi-interval than ordinal in character and may be subject to parametric statistics. For this reason, standard deviations have not been reported by the UDSMR or in this article for FIM items but are reported for total FIM scores. There is support for taking this position in the literature. For instance, in conducting interrater reliability studies, the parametric intraclass correlation coefficient is not recommended for analysis of ordinal or nominal data,22 but it is applicable to analysis of quasi-interval data.23 Further, parametric intercorrelations of the FIM total and domain scores with several other functional assessment scales and interval measures of severity of traumatic brain injury were little different than intercorrelations performed on FIM scores Physical Therapy/Volume 74, Number 5/May 1994

9 transformed by Rasch analysis to an interval scale measure.l3 The FIM is likely not appropriate for all applications. It measures disability, not impairment or handicap. It seems to work well for program evaluation; it may be: useful as a component for a rehabilitation prospective payment systemz4; and it seems to be useful for classifying patient level of disability, predicting the need for assistance at home,9jo and predicting certain outcomes such as discharge level of function, length of rehabilitation stay, or discharge destination.".'* The FIM can be an adjunct (like a thermometer) for clinical management of patients by clinicians, but it cannot substitute for a thorough assessment and daily monitoring of patient function. Because the FIM consists of only 18 items and does not measure impairment (eg, muscle weakness or restricted range of motion), it has limited prescriptive clinical application. The FIM is sensitive to change in patient function during rehabilitation but could require additional components to become sensitive to change in special cases, such as high-level spinal cord injury or very severe brain trauma, where function change may be small, or for inpatient pain management and outpatient management, where level of patient function is already very high. Care should be exercised in utilizing database information in a clinical setting. Databases reflect average values for a sample of subjects, sometimes a very large sample. There is a temptatic~n to use the database as if the data applied to the therapist's patient, say, Mrs Jones who has had a stroke. In database samples, there is always variance around the average (mean), which reflects differences in patients, clinical settings, and numerous other variables. Notice that the average stroke admission FIM score in the UDSMR sample in 1992 was 62, with a standard deviation of about 22 (Tab. 4). There is a fair chance that Mrs Jones falls within this standard deviation, but her admission FIM score could be anywhere from 40 to 84 (or an item average score range of for all 18 items). The same consideration applies to discharge FIM level, FIM gain, or LOS. So, if the therapist compares Mrs Jones' characteristics with database averages, one should expect that her data will likely not match the database averages. On the other hand, data from a sample of patients with stroke from a facility with a sufficiently large sample of patients (say, 30 or more) should compare favorably with admission FIM averages from a stroke database, such as that reported in Table 4. If there are significant differences, then it will be helpful to determine why. For instance, if a facility sample of patients with stroke has a significantly higher admission FIM score than the UDSMR average, this could be explained by any one or more of the following: 1. Time from stroke onset to rehabilitation admission could have been significantly delayed. During that delay patients may have had therapy while in the acute care setting and the "natural" function recovery process may have begun, both increasing function. 2. Significantly younger patients with stroke have higher admission FIM scores. l6 3. Facility policy results in more severely disabled patients with stroke being referred to skilled nursing facility care. 4. "Admission" FIM patient assessment was conducted later than 72 hours after admission, the limit set by the UDSMR. If "admission" FIh4 scores were collected just before the first weekly patient conference, then nearly a week could have passed since admission. Patient function gain can be substantial during the first week. 5. Facility staff consistently rate patients at admission at a higher functional level because the staff are not appropriately trained and credentialed for reliability. Significantly lower facility admission FIh4 scores can often be explained by these same factors, but operating in the inverse direction, that is, early entry, older patients, policy excludes admission of high-functioning patients, early assessment, or staff consistently assesses function low. Functional Independence Measure discharge and gain scores and LOSS can be compared and evaluated in similar ways. When a facility's average scores are significantly higher or lower than those for an appropriately comparable region or national Sample, an important opportunity is provided to find out what accounts for the difference. This information feedback is a valuable management tool, which can direct self-evaluation and adjustment of policies and procedures, when adjustment is indicated. These adjustments should lead to improved effectiveness and efficiency of care and to improved disability outcomes. Uniform assessment of patient function and documentation of resource use during and following inpatient medical rehabilitation can provide a rational, predictable basis for rehabilitation practice and enhance effectiveness and efficiency of management of rehabilitation outcomes. These concepts and the baseline data reported could help focus future physical therapy research. References 1 International Cla.sszJication of Impairments, Disabilities, and Handicaps. Geneva, Switzerland: World Health Organization; Granger CV, Hamilton BB, Keith RA, et al. Advances in functional assessment for medical rehabilitation. Topics in Geriatric Rehabilitation. 1986;1: Hamilton BB, Granger CV, Sherwin FS, et al. A uniform national data system for medical rehabilitation. In: Fuhrer M, ed. Rehabilitation Outcomes: Analysis and Measurement. Baltimore, Md Paul H Brookes Publishing Co Inc; 1987: Keith RA, Granger CV, Hamilton BB, Sherwin FS. The Functional Independence Measure: a new tool for rehabilitation. In: Eisenberg MG, Grzesiak RC, eds. Advances in Physical 'Therapy /Volume 74, Number 5Nay 1994

10 Clinical Rehabilitation: Vol I. New York, NY: Springer-Verlag New York Inc; 1987: Guide for Use of the Uniform Data Set for Medical Rehabilitation (Version 3.1). Buffalo, NY: State University of New York at Buffalo, Hamilton BB, Iaughlin JA, Granger CV, Kayton RM. Interrater agreement of the sevenlevel Functional Independence Measure (FIM). Arch Phys Med Rehabil. 1991;72:790. Abstract. 7 Dodds TA, Martin DP, Stolov WC, Deyo RA. A validation of the Functional Independence Measurement and its performance among rehabilitation inpatients. Arch Phys Med Rehabil. 1993;74: , 8 Heinemann AW, Hamilton BB, Granger CV, et al. Final Report: Rating Scale Analysis of Functional Assessment Measures (Project #H133H Department of Education, National Institute on Disabiliy and Rehabilitation Research). Chicago, 111: Rehabilitation Institute of Chicago; Granger CV, Cotter AC. Hamilton BB, Fiedler RC. Functional assessment scales: a study of persons with multiple sclerosis. Am J Phys Med Rehabil. 1990;71: Granger CV, Cotter AC, Hamilton BB, Fiedler RC. Functional assessment scales: a study of persons after stroke. Arch Phys Med Rehabil. 1993;74: , 11 Heinemann AW, Linacre JM, Wright BD, et al. Prediction of rehabilitation outcomes with disability measures. Arch Ph-ys Med Rebahil. 1994;75: Oczkowski WJ, Barreca S. The Functional Independence Measure: its use to identify rehabilitation needs in stroke survivors. Arch Phys Med Rehabil. 1993;74: Hall KM, Hamilton BB, Gordon WA, Zasler ND. Characteristics and comparisons of functional assessment indices: Disability Rating Scale, Functional Independence Measure, and Functional Assessment Measure. J Head Trauma Rehabil. 1993; 8: Silverstein B, Fisher WF', Kilgore KM, et al. Applying psychometric criteria to functional assessment in medical rehabilitation, 11: defining interval measures. Arch Phj~s Med Rehabil, 1992;73: Dahmer ER, Shilling MA, Hamilton BB, et al. A model systems database for traumatic brain injury. J Head Trauma Rehabil. 1993; 8: Granger CV, Hamilton BB, Fiedler RC. Discharge outcome after stroke rehabilitation. Stroke. 1992;23: Granger CV, Hamilton BB. UDS report: the Uniform Data System for Medical Rehabilitation report of first admissions for Am J Phys Med Rehahil. 1992;71: Granger CV, Hamilton BB. The Uniform Data System for Medical Rehabilitation report of first admissions for Am J Phys Med Rehabil. 1993;72: Wilkerson D, Hildebrandt LA, Granger CV, Hamilton BB. Team involvement in rating the Functional Independence Measure (FIM). Arch Phys Med Rehahil. 1992;73:966. Abstract. 20 Survey of Medical Rehabilitation Hospitals and Programs Chicago, 111: American Hospital Association; 1993: Wright BD, Linacre JM. Observations are always ordinal; measurements, however, must be interval. Arch Phys Med Rehabil. 1989;70: Bartko JJ, Carpenter WT. On the methods and theory of reliability. J N m Ment Dis. 1976; 163: Tinsley HE, Weiss DJ. Interrater reliability and agreement of subjective judgments. Journal of Counseling Psychology. 1975;22: Stineman MG, Escarce JE, Goin JE, et al. A case-mix classification system for medical rehabilitation. Med Care. 1994;32; Quantity Cases Binders Charge (minimum of $15 required) Am Express Visa Mastercard Diners Club Exp. Date - $ 7.95 $ 9.95 $39.95 $52.95 Please print: Name Add $1 per item for postage and handling; outside the United States, add $2.50 for each item, US funds only. PA residents add 7% sales tax. Credit orders also accepted. Call toll free, seven days per week, 24 hours per day, 1-800/ Physical Therapy /Volume 74, Number 5Nay 1994