Multidisciplinary versus physiotherapy-only weekend rehabilitation: A prospective cohort study

Background: This study aims to investigate the impact of multidisciplinary Saturday rehabilitation (MSR) on length of stay, functional independence, gait and balance when compared to a 6-day physiotherapy-only service in a pragmatic setting. An economic evaluation of the intervention conducted from the perspective of the healthcare provider is included. Methods: A prospective cohort study with a historical control was conducted in an Australian private mixed rehabilitation unit to compare a multidisciplinary and physiotherapy-only 6-day rehabilitation service. Clinical outcomes included the Functional Independence Measure (Motor, Cognitive, Total), gait speed (10 Meter Walk test) and five balance measures (Timed Up and Go test, Step test, Functional Reach, Feet Together Eyes Closed and the Balance Outcome Measure of Elder Rehabilitation). Economic outcomes were rehabilitation unit length of stay and additional treatment costs. Results: A total of 366 patients were admitted to the rehabilitation unit over two 20-week periods. The prospective cohort (MSR) had 192 participants and the historical control group (physiotherapy Saturday rehabilitation) had 174 participants). Participants in the historical control group had lower total and cognitive Functional Independence Measure scores (p < 0.078), and generally performed at a lower level on admission gait and balance measures compared to the prospective cohort. More participants in the prospective cohort attended weekend therapy, attending more sessions and spending more time in therapy compared to those in the historical control group (p < 0.012). After controlling for differences in admission Functional Independence Measure scores, length of stay was reduced by 1.39±0.77 days. The economic evaluation estimated cost savings of $1,536 per patient. The largest savings were attributed to neurological patients $4,854. Traumatic and elective orthopaedic patients realised cost savings per admission of $2,668 and $2,180, respectively. Conclusions: Implementation of MSR results in a more efficient service, enabling a greater amount of therapy to be provided over a shorter length of stay. The provision of a multidisciplinary Saturday rehabilitation is potentially cost reducing for the treating hospital. Trial registration: not applicable.

Providing weekend rehabilitation will likely incur additional costs for facilities. However, economic evaluations have suggested that Saturday multidisciplinary rehabilitation may reduce costs per quality-adjusted life year gained 17,18 with potential reductions also found in incremental cost-effectiveness ratios at 30 days 17 16.38) and conforms to the Helsinki Declaration. Individual patient consent to participate in the study was not required by the ethics committee as the service was deemed usual practice.

Intervention
The rehabilitation unit services a mixed adult caseload. Participants in both groups received usual weekday (Monday to Friday) rehabilitation consisting of nursing, medical, and individualised PT and OT (one hour each, per weekday) care, with speech pathology and dietetic involvement as required. The control group were eligible to receive a Saturday PT service consisting of 3.5 hours of PT on Saturday, delivered as group or individual sessions in the therapy gym or ward, staffed by a PT and an Assistant-in-Nursing who provided porterage and therapy assistance. Participants were deemed eligible by their treating physiotherapist if they were likely to deteriorate over the weekend without PT input, were making functional improvements and would benefit from weekend PT input, were admitted on a Thursday or Friday, or admitted for a stay of less than one week. Patients were excluded from Saturday therapy if they consistently refused usual weekday PT.
The intervention group were offered a MSR service, consisting of four hours each of PT and OT, with an allied health assistant providing porterage and therapy assistance. There was no change to PT service and eligibility criteria. The intervention group were eligible to attend the Saturday OT service if they were admitted on a Friday, required an initial assessment (activities of daily living, cognitive or neurological assessment), required compression therapy, were neurological patients who would benefit from weekend OT, or required additional OT prior to discharge. A maximum of two activities of daily living assessments could be scheduled each Saturday. OT was provided in group or individual sessions, in the therapy gym or ward. Participants could receive both PT and OT Saturday services.

Data Collection
Patient demographic data collected included age, sex, primary diagnosis, discharge destination, rehabilitation inpatient LOS and nine indicators of patient capability (clinical measures of functional independence, gait speed and balance), measured on admission and discharge to the rehabilitation unit. Functional independence was recorded using Functional scores. 19,20 Gait speed was measured using the 10 Meter Walk Test (10MWT). 21,22 Five valid and reliable measures of balance with older populations were used: the Timed Up and Go (TUG) test, 23,24 Step test, 25,26 Functional Reach, 27,28 maximum Feet Together Eyes Closed (FTEC) test 29 , and the Balance Outcome Measure of Elder Rehabilitation (BOOMER). 30,31 Distributions for the 9 dependent variables of interest are reported in Figure A.1 in the Appendix.
The economic evaluation was conducted with financial data obtained from St Andrew's War Memorial Hospital's human resources department to estimate the costs of providing 20 weeks of Saturday rehabilitation for both groups. Estimates of variable costs (e.g., wages) and fixed costs (e.g. hospital overheads & ward expenses) were included. Allied health and nursing staffing costs were based on wage rates per hour (inclusive of weekend loading and on-costs). Estimates of average cost per bed-day published by the Hospital Pricing Authority 32 were used to monetise potential savings due to reduced LOS. All rehabilitation costs were collected in 2017 Australian dollars and adjusted to 2020 Australian dollars using the Australian consumer price index. 33

Statistical Analysis
First, to explore the effect of MSR on patient health at discharge, the following multivariate regression model was estimated:

RESULTS
There was no statistically significant difference between the intervention and control groups in age, sex, medical diagnosis, acute inpatient care or discharge destination (    After controlling for differences in sex, age and medical diagnosis, some measures of patient 2 function at discharge were marginally greater in the intervention group (see Table 3). 3 Intervention group participants scored one point better on the FIM Cognitive (1.056, p=0.022) 4 but there was no difference in the FIM Total . The intervention group had a faster 10MWT 5 (0.078, p=0.042) and a slightly better BOOMER score (1.141, p=0.094), although the Step 6 Test was worse (-3.940, p=0.017). The number of observations in the regression models 7 which analysed gait and balance were reduced due to incomplete data collection (Table 3). 8 14

Economic Evaluation
The costs of providing 20 weeks of rehabilitation to the control and intervention groups were estimated to be $12,784 and $23,180, respectively (  Table 5 for details). A two-way sensitivity analysis of the parameters, reduced LOS (1.39±0.77) and cost per bed-day ($1,144±$305), using Monte Carlo simulation (n=1000) indicated cost effectiveness (i.e., >$0) in approximately 95% of simulations. Net Savings per patient $1,536 Notes: Cost per rehabilitation bed-day was reported in 2014 AUD 32 using DRG code Z60Z from "Cost weights for AR-DRG Version 7.0 Round 18 (2013-14) Public Sector Sample DRG" (mean cost / mean LOS) and adjusted to 2020 Australian dollars (AUD) using the Australian consumer price index 32, 33 . Treatment costs were reported as 2016 AUD (see Appendix A.1 and A.2) and adjusted to 2020 AUD using the Australian consumer price index. 33 Abbreviations, LOS, length of stay; SD, standard deviation. Model 3, which includes a set of binary variables that interacted medical diagnoses with MSR, found that within the treatment group only neurologic and orthopaedic patients had a statistically significant reduction in LOS. The marginal effect for neurological patients was a reduction of 4.4 days (Table 3). Hence the implied cost savings for patients with a neurological diagnosis is $4,854 per treated patient. Both traumatic and elective orthopaedic patients also benefited from MSR with a reduced LOS resulting in implied cost savings of $2,668 and $2,180 per patient, respectively.

DISCUSSION
This paper used a pragmatic prospective cohort study design to analyse the effect of MSR on patient outcomes admitted to a 20-bed rehabilitation ward in a private hospital located in Brisbane, Australia. The aim was two-fold, first to analyse the impact on LOS and functional status, and second to conduct an economic evaluation from the perspective of the healthcare provider. Outcome measures of functional status included functional independence, gait and balance. LOS and hospital cost data were obtained for the economic evaluation. Providing rehabilitation therapy across six days (at least in stroke populations) appears to result in better patient outcomes compared to seven-day rehabilitation. 35 Additionally, providing rehabilitation across six days seems to be prevalent in Australian rehabilitation facilities. 35 This current study adds to the evidence that rehabilitation six days a week is beneficial for patients and service providers alike.
Interestingly, until this current study, greater reductions in LOS have been found with facilities providing PT 8, 35 compared to multidisciplinary weekend services. 9,14,36,37 As this has been one of the few studies investigating weekend therapy to find a significant difference in LOS, this multidisciplinary service provision model warrants further pragmatic investigation to determine if these results are reproducible in different service models and settings. This reduction in LOS may have far reaching effects, not just for patient outcomes and health service costs, but in terms of improved patient flow through both rehabilitation units and hospitals. Certainly allied health managers perceive improved patient flow and quality of care are benefits associated with weekend services, at least in acute care. 38 An associated increase in throughput occurred in this rehabilitation unit with approximately 10% more patients admitted during the intervention period compared to the control period. This may have led to an improved flow of patients through the hospital and possibly reduced rehabilitation waiting lists.
Participants in the intervention group in this current study had higher scores on measures of functional independence, and some balance measures on admission. At discharge, largely both groups had similar functional independence, balance and gait. It is reasonable to suggest that discharge is likely determined by patient readiness, functional performance and preparedness of the home environment. 38 Previous studies have reported similar discharge function from inpatient rehabilitation. 12,39 Interestingly differences in cognitive function were noted between the two groups at discharge. The intervention group had better cognitive function at discharge compared to the control group, though both groups scores would suggest discharge home would be likely. Results obtained from observational data are always subject to the ceteris paribus caveat, and causal inferences should be drawn with caution. Although our statistical models have controlled for some important observed differences between the control and the intervention groups, it is always possible that unobserved differences could confound our results.
Cost savings identified in the economic evaluation corroborate an evolving literature that suggests the provision of weekend rehabilitation services may deliver an economic dividend.
Previous randomised controlled trials have reported that weekend rehabilitation may reduce hospital LOS. 8,9 A cost utility analysis has also reported probable cost effectiveness at 30 days 17 and 12 months 18 post-discharge. We found that rehabilitation LOS reduced on average by 1.39 days, with long-stay inpatients appearing to benefit most from the intervention. Additionally, diagnosis also appeared to be important with sub-analyses confirming larger LOS reductions for neurological and orthopaedic patients. It is perhaps not surprising that those who stay longer and have complex conditions would show greater benefit from the additional therapy offered through a MSR service; perhaps further validating the need for this service.

Limitations
A potential limitation of the cost analysis was that the average cost of a rehabilitation bedday was used as proxy for the marginal cost of a rehabilitation bed-day. This can result in an overestimation of cost-savings when the cost of the final day of admission is substantially less than the cost of an average bed-day. 40 This can frequently occur with acute inpatient admissions. However, our cost modelling has assumed that the costs of a rehabilitation bedday did not significantly decline over the duration of the admission. A second limitation is that the economic evaluation was restricted to the perspective of the healthcare provider.
Conducting an economic evaluation from a societal perspective, which included improvements in the FIM and BOOMER scores, may capture relevant improvements in patient health not included in this analysis. Finally, the assessors were not blind to group allocation as it was considered usual care, however they were not aware of the focus of the study at the time of data collection, thus minimising the potential for assessor bias.

CONCLUSION
The provision of a MSR service comprising PT and OT leads to a greater reduction in LOS compared a to a 6-day PT service, even when controlling for discrepancies in admission function. More participants attended weekend therapy and received a greater amount of therapy with multidisciplinary Saturday rehabilitation. The provision of a service is potentially cost reducing for the treating hospital. Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

LIST OF ABBREVIATIONS
Competing interests: The authors declare that they have no competing interests. Authors' contributions: EC, SB and SK developed the study design. EC completed data collection, analysis and interpretation of patient data. SB, SK and DR assisted in data analysis and interpretation of patient data. EC, SB, SK and DR contributed to writing these sections of the manuscript. DR analysed and interpreted the economic data and completed this section of the manuscript. All authors contributed to, read and approved the final manuscript.