LONG-TERM DISABILITY 1 and poor recovery 2 are common

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1 ORIGINAL ARTICLE Prediction of Discharge Destination After Stroke Using the Motor Assessment Scale on Admission: A Prospective, Multisite Study Sandra G. Brauer, PhD, Paul G. Bew, MPhty, Suzanne S. Kuys, BPhty, Mary R. Lynch, MPhty, Greg Morrison, BPhty ABSTRACT. Brauer SG, Bew PG, Kuys SS, Lynch MR, Morrison G. Prediction of discharge destination after stroke using the Motor Assessment Scale on admission: a prospective, multisite study. Arch Phys Med Rehabil 2008;89: Objective: To determine if admission functional status, measured with the Motor Assessment Scale (MAS), was predictive of discharge destination to home or residential aged care in patients with stroke undergoing rehabilitation. Design: Cohort study. Setting: Inpatient rehabilitation units. Participants: Adults (N 566) diagnosed with stroke undergoing inpatient physiotherapy at one of 15 units in Australia. Intervention: Multidisciplinary rehabilitation. Main Outcome Measure: Discharge home versus residential aged care. Results: Prestroke residential status, gait ability measured with the MAS (MAS-5), rolling ability (MAS-1), and age were able to correctly predict 99% of patients with stroke discharged home and 33.3% discharged to residential aged care facilities, producing an accuracy of 87.3%. Odds ratios indicate that for every 1-point increase in MAS-5 (gait), subjects were 1.66 times more likely to go home (95% confidence interval [CI], ; P.001). Similarly, for every 1-point increase in MAS-1 (rolling), subjects were 1.28 times more likely to go home (95% CI, ; P.01). Conclusions: Two items of the MAS assessed on admission to rehabilitation gait and rolling in conjunction with basic demographic information of age and prestroke residential status, were highly predictive of discharge from rehabilitation to home. Key Words: Cerebrovascular accident; Outcome assessment (health care); Patient discharge; Physical therapy; Rehabilitation by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation From the Division of Physiotherapy, School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia (Brauer, Lynch); Prince Charles Hospital, Chermside, Australia (Bew); School of Physiotherapy and Exercise Science, Griffith University, Gold Coast, Australia (Kuys); and Department of Physiotherapy, Princess Alexandra Hospital, Woolloongabba, Australia (Kuys, Morrison). Presented to the Australian Physiotherapy Association National Neurology and Gerontology, November 2005, Melbourne, Australia. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to Sandra G. Brauer, PhD, Div of Physiotherapy, School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Qld 4072, Australia, s.brauer@shrs.uq.edu.au /08/ $34.00/0 doi: /j.apmr LONG-TERM DISABILITY 1 and poor recovery 2 are common sequelae after stroke. After inpatient rehabilitation aimed to reduce this disability, 75% to 85% of stroke survivors are typically discharged home. 3,4 Approximately 50% of these need assistance with physical activities such as mobility and transport, and household chores. 5 In most cases, this assistance is provided by informal caregivers such as family or friends. 6 Caring for a person poststroke at home requires modifications to lifestyle and the physical environment, and can have large personal, time, and hidden economic costs. 6-8 If discharge destination could be predicted early in the rehabilitation period, improved planning and realistic rehabilitation goals could result in reduced costs and better preparation by informal carers, and could facilitate improved access to care provided by agencies. Poststroke discharge destination has been reported to be predicted by a variety of factors including age, lesion type, continence, cognitive impairment, prestroke residential status, available social networks, and caregiving resources Although the ability of these factors to predict discharge home varies with the predictive model, functional ability on admission to rehabilitation appears to consistently prove useful in predicting discharge destination in stroke survivors. Patients with a higher Barthel Index 14 or higher FIM score within 1 week of admission to rehabilitation are more likely to be discharged to living in a home environment. 11,15-17 A low motor FIM instrument score has also been associated with a high risk of needing to change living status, particularly if previously living alone. 3 Other functional measures including admission balance ability, as measured with the Berg Balance Scale (BBS), 12,18,19 and measures of gait ability 9,10,13,20 have also been shown to predict discharge destination poststroke. However, there are limitations to the generalizability of these studies due to incomplete data sets, 3 or data gathered from a single site. 12,13,18,20 Many studies also use a retrospective design. 3,13,17,21 In addition, there are also limitations in some measures used to predict discharge destination, such as (1) being time consuming to perform (eg, the FIM instrument), (2) having floor effects that do not capture the ability of lower functioning patients (BBS), or (3) ceiling effects whereby despite scoring 100%, there are still significant limitations in functional mobility (FIM), and (4) not frequently being used by clinicians in Australia. 4,10 The Motor Assessment Scale (MAS) 22 is a measure of functional recovery poststroke that is widely used It is relatively quick and easy to administer, involving assessment of routine tasks ranging from rolling to advanced hand activities. Although the MAS measure of sitting balance 1 week poststroke has been shown to be associated with Barthel Index at discharge, 26 its ability to predict discharge destination is unknown. Thus the aim of this prospective, multicenter study was to determine whether premorbid residential status, age, and functional level on admission to rehabilitation for patients with

2 1062 DISCHARGE DESTINATION AFTER STROKE, Brauer stroke as measured with the MAS, can predict discharge destination. METHODS Participants All patients admitted to 15 rehabilitation units with a primary diagnosis of stroke who were referred to physiotherapy from September 2001 through to February 2002 and from March 2004 through to March 2005 were eligible to be included in the study. We admitted patients to the study if they were medically stable and were able to give informed consent. The rehabilitation units ranged from 8 to 78 bed wards, with a mean of 24.1 beds. These units predominantly serviced a metropolitan region (n 13) with 2 in major rural centers. Twelve units were public facilities and 3 were private facilities. Ethics approval for this study was obtained from affiliated university and hospital medical research ethics committees. Measures We recorded functional level using the MAS by the treating physiotherapist. The MAS is a battery developed for stroke patients assessing 8 motor items, each scored on a 0 to 6 scale. Higher scores indicate a greater level of independence, quality of movement pattern, and complexity of tasks completed. The items include: rolling, lie to sit, sitting balance, sit to stand, gait, upper-arm function, hand movements, and advanced hand activities. It takes 10 to 30 minutes to administer, depending on the patient s functional status. The MAS is significantly correlated with the Fugl-Meyer Assessment for all items except sitting balance (correlations range,.65.93) 27 and has established inter- and intratester reliability. 22,28,29 To ensure consistency in interpretation of the scale across treating physiotherapists, they all attended common training sessions through videoconference, a CD-ROM training resource was developed and available to all treating physiotherapists, and a central contact person at each participating rehabilitation unit was established for queries. Residential status prestroke and discharge destination were categorized as either home, hostel, or nursing home from medical chart notes. Hostel and nursing home residential status was combined to produce a variable indicating discharge to any residential aged care facility. Additional subject characteristics recorded from the medical chart included: age, sex, side of stroke, time since stroke until admission to rehabilitation, and length of stay in rehabilitation. Data Analysis We present patient characteristics and performance scores using descriptive statistics. Spearman rank correlation coefficients were used to correlate admission functional MAS scores with discharge destination (0 home, 1 hostel, 2 nursing home). No multicolinearity was evident between predictors when assessed using the colinearity diagnostics of SPSS. a A multinomial forward stepwise logistic regression was used to predict discharge destination (home vs residential aged care) from admission functional level (MAS scores with a predetermined Spearman.30), age, and prestroke residential status (home, residential aged care). Variables were entered conditionally at an significance of.05. Statistics were performed using SPSS a and significance was set at P less than.05. A repeat 10-fold cross-validation estimate of the predictive accuracy of each model was performed using R. 30,b Table 1: Participant Characteristics Characteristic n Mean SD n (%) Age (y) Stroke to rehabilitation admission (d) Length of stay in rehabilitation (d) Sex (males) (54.1) Side of stroke 560 Left 269 (47.5) Right 250 (44.6) Other 41 (7.2) Prestroke residence 558 Home 539 (96.6) Hostel 15 (2.7) Nursing home 4 (0.7) Discharge residence 554 Home 410 (74.0) Hostel 32 (5.8) Nursing home 60 (10.8) Acute ward 44 (7.9) Death 8 (1.4) Abbreviation: SD, standard deviation. RESULTS A total of 566 patients across 15 sites were admitted to the study, with discharge destination information collected from 554 subjects. Of these subjects, 410 (74%) were discharged home, 32 (5.8%) were discharged to a hostel, 60 (10.8%) were discharged to a nursing home, 44 (7.9%) were transferred to an acute ward, and 8 (1.4%) died. Most patients were living at home prior to their stroke (96.6%). Demographic characteristics are outlined in table 1. Admission functional scores across the 8 items of the MAS are outlined in table 2. The Spearman rank correlation found that all 8 admission MAS scores had a significant (P.001) correlation with discharge destination, with r values ranging from.192 to.35 (see table 2). A more dependent residence after rehabilitation (nursing home) was most associated with lower MAS scores in gait, rolling, lie to sit, sit-to-stand ability, and sitting balance scores on admission. These MAS scores had a correlation with discharge destination of greater than.30 and thus were then included in the logistic regression. Table 3 presents the adjusted odds ratios (ORs) and 95% confidence interval (CI) result of the multinomial forward stepwise logistic regression model (model A) best able to predict discharge destination to home or residential aged care facility (hostel and nursing home). Admission gait ability (MAS-5), prestroke residential status, age, and admission rolling ability (MAS-1) were included in the final model (Nagelkerke r 2.405, P.001). This model had a sensitivity (correctly predicting discharge home) of 99% and a specificity (correctly predicting discharge to a residential aged care facility) of 33.3%, with an overall predictive accuracy of 87.3% (table 4). The adjusted ORs indicate that for every 1-point increase in MAS-5 (gait), subjects were 1.66 times more likely to go home (1/.60; 95% CI, ). Similarly, for every 1 point increase in MAS-1 (rolling), subjects were 1.28 times more likely to go home (1/.78; 95% CI, ). Receiver operator characteristic (ROC) curves are presented in figure 1, with area under the curve calculations of 75% for gait ability, 73% for rolling, and 67% for age. The cross-validation estimate of accuracy of this model was.864.

3 DISCHARGE DESTINATION AFTER STROKE, Brauer 1063 Table 2: Functional Ability (admission MAS scores) Correlation With Discharge Destination and the Admission MAS Scores for Subjects Discharged to Home or Residential Aged Care Score Median (25th 75th percentile) Mean Score SD MAS Item Correlation With Discharge Destination* Home RAC Home RAC Rolling (MAS-1) (2 6) 1 (0 5) Lie to sit (MAS-2) (3 6) 3 (1 5) Balanced sit (MAS-3) (3 5) 2 (2 4) Sit to stand (MAS-4) (1 5) 1 (1 2) Gait (MAS-5) (0 4) 0 (0 1) Upper arm (MAS-6) (1 6) 1 (0 5) Hand (MAS-7) (0 6) 1 (0 4) Advanced hand (MAS-8) (0 2) 0 (0 2) Abbreviation: RAC, residential aged care. *Coded as 0 home, 1 hostel, 2 nursing home. To define more specifically the predictive functional capabilities for the clinician, the gait and rolling categories were each recoded as binary variables. The gait (MAS-5) was recoded as either unable (scoring 0 or 1) or able (scoring 2 6) to achieve the task with standby help. Rolling (MAS-1) was recoded as either unable (scoring 0 5) or able (scoring 6) to achieve the task in 3 seconds without overbalancing. These new categorical variables were entered along with prestroke residential status and age. Model B (Nagelkerke r 2.386, P.001) had a similarly high sensitivity (99.5%), but a lower specificity (19.5%), with a slightly lower overall predictive accuracy of 85.2% when compared with the previous model (see table 4). The adjusted ORs indicate that if subjects scored greater than or equal to 2 in MAS-5 (gait), they were 6.25 times more likely to go home than if scoring a1or2(1/.16; 95% CI, ). Similarly, if subjects scored a 6 in MAS-1 (rolling), they were 2.63 times more likely to go home than if scoring a5orless (1/.38; 95% CI, ). ROC curves are presented in figure 2, with area under the curve calculations of 70% for gait ability, 66% for rolling, and 67% for age. The cross-validation estimate of accuracy of this model was.835. DISCUSSION We found that MAS scores of gait and rolling ability on admission to rehabilitation, together with prestroke residential Table 3: Prediction of Discharge Home Versus Residential Aged Care Characteristics Adjusted OR 95% CI Model A Prestroke residence * (0.00 ) Gait (MAS-5) 0.60 ( ) Rolling (MAS-1) 0.78 ( ) Age 1.05 ( ) Constant 1.47 NA Model B Prestroke residence * (0.00 ) Gait (MAS-5) (0 1 vs 2 6) 0.16 ( ) Rolling (MAS-1) (0 5 vs 6) 0.38 ( ) Age 1.05 ( ) Constant 0.45 NA Abbreviation: NA, not applicable. *The large adjusted ORs are due to 96.6% having a prior residence at home. P.001; P.01. status and age were able to predict discharge destination of patients with stroke to home or residential aged care facility with an overall accuracy of 87%. This is important because, even though the MAS is widely used in Australian rehabilitation facilities, this is the first study to investigate its ability to predict discharge destination. The MAS, previous residential status, and age had a very high sensitivity at predicting discharge to home (99%) but a comparably low specificity in predicting discharge to a residential aged care facility (33.3%). This is likely to reflect the importance of issues other than the factors in our model in the decision to discharge to residential aged care facilities. This is supported by Mokler et al, 21 who were more successful in predicting stroke survivors who were not discharged home (76.6% correct) than those who were discharged home (53.4%) using the FIM functional-related groups, with the most significant variables being toilet transfer, memory, and bladder management. Our strong prediction of discharge home, however, indicates that the 4 predictors in our model (prestroke residence, gait ability, rolling ability, age) are factors important in the decision to discharge to home. Our overall accuracy of predicting discharge destination (87%) was similar to that of Rabadi and Blau, 20 who found an overall accuracy of 82% in a model using admission ambulation velocity, age, and admission FIM score. Wee and Wong 18 also found an overall accuracy of 85.3% when using family supports and admission BBS score in predicting discharge destination poststroke. Although the FIM instrument is a widely accepted measure of functional outcome, some authors have identified potential limitations to the clinical use of the FIM and BBS. These have included the time taken and specialized training required to complete the scales, 31 difficulty with scoring criteria 32,33 and possible item redundancy of the BBS. 33 Thus if the FIM or BBS are not routinely performed on patients on admission to rehabilitation, the MAS may prove of Table 4: Actual Versus Predicted Discharge Destinations Predicted Destination Destination Home RAC % Correct Actual Home Destination RAC Overall % 87.3

4 1064 DISCHARGE DESTINATION AFTER STROKE, Brauer independence, to best predict discharge home. This finding reflects the reports that most stroke survivors discharged home still require some form of physical assistance. 5 The conduct of this study over 15 public and private rehabilitation sites facilitates the generalization of findings of this study. In addition, cross-validation of the predictive models produced a high estimate of accuracy (.83). It is acknowledged that the prediction model should be validated in a second independent group of patients. 35 Our discharge rate to home (74%) was similar to other Australian prospective studies (75%) 4 and is comparable with another Australian multisite 3 study that had a discharge rate to the community of 84%, but a younger cohort (61.5y vs 72.5y). Fig 1. ROC curve for MAS-5, MAS-1, and age to predict discharge destination of home versus residential aged care. similar discharge predictive ability and take a shorter time to perform. Our ORs of the best predictive model indicate that for every increase in the MAS gait item score by one, the odds of being discharged to home increases by a factor of An increase in score in this item reflects independence, gait speed, and ability to multitask. The multiple dimensions of this scale may be a key contributor to its predictive ability for discharge home. In support, gait abilities have previously been demonstrated to contribute to prediction of discharge home. 10,13,20 Another reason for this item to prove predictive may have been the sensitivity of the scale within this item. English et al 34 found the gait item of the MAS to be sensitive to change within the rehabilitation period, showing low floor and ceiling effects. This is the first report of such a low level task (rolling) significantly contributing to the prediction of discharge destination poststroke. For every increase in the rolling score by 1, the odds of being discharged home increases by a factor of The ability to roll in bed may be a key factor for discharge home because for many stroke survivors, the failure to achieve this ability may preclude them from living alone or with a frail aging partner who is unable to provide the necessary physical assistance. Another reason for its importance in this model may be because this task involves multifaceted abilities required for home living that are different from that of gait. It requires complex motor control of the limbs and trunk and an accurate sense of orientation. This premise is supported by findings that perceptual problems 14 and poor trunk control 10 are factors contributing to discharge to a residential aged care facility. The inclusion of age and previous living arrangement in the final model with best predictive ability confirm previous studies of their importance with similar ORs. 10,13 The recoding of the MAS items into binary cutoff levels did not diminish the overall accuracy of its predictive ability and may prove of greater clinical use. The better cutoff was the description of the need for standby assistance, rather than Study Limitations It is noted that these findings may not be generalizable to all stroke survivors undertaking inpatient rehabilitation because to be included in this study, patients had to be referred to physiotherapy and to have sufficient cognitive ability to provide informed consent. Nonetheless, this inclusion criterion is likely to encompass a large proportion of stroke survivors undergoing inpatient rehabilitation. The intensity and content of rehabilitation across sites was not controlled; however, all sites had a similar multi-professional team approach to intervention. The participant characteristics, rehabilitation model and intervention principles may vary by setting and health care system, and needs to be considered when generalizing findings. CONCLUSIONS By using 2 items of the MAS, age, and previous residential status, discharge to home could be predicted in 99% of cases. Discharge home poststroke frequently requires an adjustment of lifestyle for carers, and the use of community services. Both these factors would benefit from early planning to maximize readiness of the stroke survivor and carer for community living. In demonstrating that simple demographic and clinical Fig 2. ROC curve for MAS-5 and MAS-1 recoded as binary outcomes, and age to predict discharge destination of home versus residential aged care.

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