Validation of Bedside Mobility Assessment Tool (BMAT) in Acute Orthopaedic Setting

Introduction

Mobility is integral to a patient's speedy recovery in acute care settings and this also holds true in acute orthopedics care settings due to weight bearing restrictions.¹ Immobility in acute settings can lead to complications such as pneumonia, thromboses, pressure ulcers, and urinary tract infections, which may be life threatening. Moreover, there is substantial decrease in muscle mass and function.² The rehabilitation team's primary objective is to help the patients regain their prior level of function, optimize their functioning, independence and prevent unintended complications.³ Functional bed mobility describes a person's ability to move around in his/ her environment, like moving in bed, rising from a chair, and walking.⁴ In acute orthopaedic settings, after a period of immobilization following injury or surgery, patients may have bedside mobility problems like difficulty in getting up independently, standing without support, walking without assistance, and in the long term, there may be functional decline and disability, especially in cases of lower limb fractures and elective lower limb surgeries. These patients may find limitations in their ability to move around, and most of them are confined to bed and do not move until they are encouraged and advised. Mobilizing these patients may require assistance from another person or an assistive device.

Physiotherapists have an active role in overcoming limitations in mobility and improving functional mobility in acute orthopaedic settings. Physiotherapists have an important role in assessing patients' mobility in acute care prior to physiotherapy intervention, since this assessment is an important aspect of patient care and helps the physiotherapists in planning the treatment and selecting appropriate assistive devices to progress ambulation.⁵ A comprehensive assessment enables the physiotherapist and other team members decide how to progress with mobility status, thereby delivering a high standard of care through safe and effective patient mobilization.

The physiotherapist evaluates three main areas of functional mobility namely, bed mobility, transfers, and ambulation. These areas can be effectively evaluated using outcome measures with good psychometric properties. Outcome measures are beneficial as these measures can be monitored and compared over time and assess the change in mobility needs. Several mobility- related evaluation outcome measures are used by physiotherapists and other health care workers.⁶ The available functional mobility assessment outcome measures in orthopaedic settings are, Functional independence measure (FIM), De Morton Mobility Index (DEMMI), Modified Elderly Mobility Scale, Timed Up & Go Test (TUG), Performance Oriented Mobility Assessment, ICF-based Basic Mobility Scale, Lower Extremity Functional Scale and Hierarchical Assessment of Balance and Mobility (HA-BAM).^6-11 The existing outcome measures are not appropriate for use in acute orthopedic settings where the patient may not be weight bearing and may be using assistive device. These outcome measures are reliable and valid in a few subgroups, but have limitations like the limited capability to display the full range of mobilization. For example, Functional Independence Measure (FIM) takes into consideration transfers onwards and does not assess bed mobility. Some of the aspects of bed mobility are precursors to transfers and ambulation. Other limitations of outcome measures are time consumption, and limited or no guidance given on associated safe patient handling and transfers. Therefore, it becomes necessary to assess this in the early post-operative period in acute orthopedic setting for decision making on advancing mobility. After reviewing the literature, a tool namely ‘Bedside Mobility Assessment tool (BMAT)’ used in the nursing discipline was identified which is designed to address existing tool limitations.¹² BMAT was developed by Banner Health as a standardized tool for nurses to measure the patient's mobility levels.¹³ It has existed since 2003, and the most recent version is BMAT 2.0. Unlike the previous version, it now addresses bilateral non-weight bearing patients and bed rest orders. BMAT promotes maximal patient participation while reducing caregiver and patient injury. It teaches the healthcare provider how to lead the patient through a four-step functional task list for determining the patient's level of mobility, like Mobility Level, and recommends the equipment and tools needed to lift, transfer, and move the patient safely.¹² This tool has been used by nurses in other acute settings like ICU and medical surgical units, has shown good psychometric properties and studies have shown a decline in injuries before and after the implementation of the BMAT emphasizing the link with a rise in more frequent usage of safe patient handling techniques. It is potentially an effective tool to be used in patients after orthopaedic surgeries.^13-15

The patient's mobility status can influence treatment, patient handling, transfer decisions, and outcomes, including fall risk. With increasing importance given to early mobility in acute orthopaedic settings, especially in patients with lower limb fractures and elective lower limb surgeries, determination of bed mobility level becomes essential to plan physiotherapy intervention and progress to ambulation. Despite the availability of several mobility-related outcome measures with their merits and demerits, none of the outcome measures effectively addresses limitations like the capability to display full spectrum of transfers (bedside to transitions and independent walking) and guidance on selecting appropriate assistive devices based on mobility levels. Out of several outcome measures, BMAT and ICU Mobility Scale are the quick and suitable outcomes measures for acute care settings. BMAT was designed to address the limitations of existing tools and is a latest evidence-based tool used by nurses to assess a patient's mobility level and mentions a list of assistive devices. Physiotherapists are mobility experts but the mobility status of patients is not properly transferred to nurses. Therefore, we need an outcome measure with cross disciplinary usage and BMAT fulfils this role, enabling other healthcare professionals to encourage mobility in safe mode. BMAT has been used in acute settings other than orthopaedic like in ICU and medical-surgical units and the findings have shown good clinometric properties. ICU Mobility Scale is another outcome measure which is equivalent to the gold standard for use in acute settings. Most of the components of BMAT are matching with ICU Mobility Scale. Since BMAT is potentially a good tool for use in acute orthopaedic settings, there is a need to validate BMAT with ICU Mobility Scale in acute orthopaedic settings.

Aim of the Study

The aim of the study was to validate BMAT in an acute orthopedic setting with objectives to validate matched components of BMAT against ICU Mobility scale (IMS) in acute orthopaedic setting using intra class correlation coefficient between the raters for BMAT and between BMAT and ICU Mobility scale (IMS).

Materials and Methods

The observational study was conducted in JSS Hospital inpatient orthopedic ward, Mysuru during May 2021 to February 2022. The study was approved by the institution ethical committee (IEC), JSS Medical College (JSSMC/IEC/090721/10NCT/2021-22). Sixty four subjects (n=64) were required and the required sample size was calculated based on the estimation of population proportion (60%) with specified relative precision (0.20) and desired confidence interval (CI) of 95% and an alpha value (α) of 0.05.

A detailed review of the patient case file was done for all post operative patients admitted in orthopedic ward. Patients were selected based on inclusion and exclusion criteria using purposive sampling method. All the cognitively competent patients aged more than eighteen years in an acute orthopaedic ward as measured by Mini-Cog test and with upper or lower extremity fractures stabilized surgically for a period of less than two weeks were included in the study. Patients who were advised bed rest and who were contraindicated for mobility including those with unstable pelvic and spinal fractures and / or with bilateral upper extremity or lower extremity amputation and/or patients with bilateral upper extremity or lower extremity fractures were excluded from the study.

In this study, we took assistance from two physiotherapists as “raters” for assessing the mobility of the patients. These raters had an experience of more than one year and were qualified with a degree of Bachelors in Physiotherapy. The raters were selected based on convenience from the same study setting. The age group of the raters was between 25-30 years. The study was conducted in five phases.

Phase I: identification of research gap and obtaining permission for the research

The research gap and need were identified through literature review. The expert’s opinion was taken on the need for a suitable scale in acute care. Based on the review, the main research gap was identified. Since BMAT is a valid and reliable tool and there is paucity in literature on its usage and applicability in acute orthopaedic settings, there is a need to validate this tool. The study methodology was framed by reviewing literature and library resources.

Phase II: Pilot study and standardization

The pilot study was conducted involving ten patients, with two raters. The two raters performed the mobility assessment using BMAT and IMS scales. The two raters were physiotherapists with Bachelors of Physiotherapy degree and one year of experience in inpatient department. The data were entered in an Excel sheet and analyzed for matching components. Based on the process and findings of pilot study, the feasibility of the present study was evaluated. The study methodology was found to be feasible with appropriate changes done accordingly.

Findings from pilot study: A requirement for training of raters through videos and hands on training was noted. The timing between the assessments was finalized as two hours, and the need for matching of components was identified followed by validation of matching components.

Phase III: Matching the components of BMAT with ICU Mobility Scale

The matching of components of both the scales was done by taking consensus from three experts with five years of clinical and teaching experience in orthopaedic and cardiorespiratory departments (Table 1).

Phase IV: Training of the raters

To evaluate the mobility of the patients, two independent raters were selected. Both the raters were qualified physiotherapists having more than one year of experience in acute settings. Both physiotherapists received training on mobility assessment through videos and were given pamphlets for reference. A trial round was also conducted to clarify doubts and check if they were competent enough to carry out the assessment.

Phase V: Subject recruitment

The principal investigator recruited the patients using purposive sampling strategy based on inclusion and exclusion criteria after analyzing the patient case sheets. All the potential candidates were informed about the study, and were provided informed consent forms in their native language. The subjects who consented were included in the study. All the patients were screened by the principal investigator to check for any cognitive impairment using "Mini-Cog Test”. Patients with score between 3-5 in Mini-Cog test were selected for the study. All the patients who scored less than 3 on Mini-Cog test were acknowledged and excluded from the study.

Phase VI: Data collection

The selected patients were allotted to a particular rater and scale initially by the principal investigator using lottery method. The demographic data of all the patients was also collected by the principal investigator. The time gap between the initial rater and the second rater was maintained to a minimum of two hours and was completed within the end of the day. The rater’s choice of carrying out the assessment was based on their convenience; for example, if rater 1 carried out the assessment in the morning, the rater 2 assessed after two hours and vice versa on different days.

The mobility levels of a total of sixty-four patients were assessed by two raters using the Bedside Mobility Assessment Scale and ICU Mobility Scale after one hour. This one-hour gap was the rest period for the patient. The mobility assessments of the patients by the raters using both the scales were limited to a maximum of three assessments per day due to time constraints and availability of the raters. The scores of both the scales along with remarks for each patient were recorded by the raters on Case Record Form and the collected data were transferred to digital form. The data was transferred to an Excel sheet, crosschecked and verified by the principal investigator. The median and interquartile range (IQR) for each group were also determined to allow the score results to be shown within the context of the raters score scale. The scores of the BMAT and ICU Mobility scales by the two raters were analyzed using the intraclass correlation coefficient using model 2 and 95% confidence interval on SPSS software version 22.2,5,10,16

Results

A total of sixty- four patients in the acute orthopaedic setting met the inclusion criteria and were enrolled in the study. The study included fifty-three men and eleven women with a mean age of 41.3±17 years (Mean ± SD). Table 2 shows patient demographics and surgery - related information. Six patients were in BMAT ‘Mobility Level 1’, nine patients were in BMAT ‘Mobility Level 2’, thirty-one patients had BMAT ‘Mobility Level 3’ and eighteen patients were in BMAT ‘Mobility Level 4’. Median and Inter Quartile Range (IQR) for BMAT and IMS scores are as shown in Table 3. The results show that the scores are within the context of the raters score scale.

Interrater reliability was analyzed for BMAT components between rater-one (R1) and rater-two (R2) using intraclass correlation coefficient (ICC). The agreement between the two raters for BMAT is shown in Table 4. There is an excellent inter-rater reliability between raters at a 95% confidence interval (ICC=0.95). Intraclass correlation coefficient was also done to determine if there was correlation and agreement between the matched components of BMAT and IMS (Table 5). Excellent agreement for the same was noted (ICC = 0.96).

Visual representation of agreement between BMAT and IMS was done using Bland Altman Graph (Figure 1). The presentation follows the same sequence as data analysis and is presented in tables (Table 4, 5).

Discussion

Hospitalization has been linked to functional deterioration in patients, which is more severe in the elderly and following surgery. Reduced mobility, which may affect independence and quality of life, is one of the most significant features of functional decline during hospitalization. Patient's mobility may impact the treatment approach and their recovery. Assessing and managing patients' mobility status and safe mobilization is vital due to the unavoidable impact of immobility and falls. This study analyzed the validation of BMAT by anchoring with IMS in acute orthopaedic setting. Through pilot study, the study procedure was standardized from patient recruitment to data collection which yielded minimum errors during the data collection period. The principal investigator on selecting the BMAT and IMS found that both had different scoring patterns in spite of components matching. Experts from the institute matched the components which was used for checking the feasibility of usage and later for the data analysis. The matched components were validated by three experts and consensus was obtained.

In the study, very minimal variations in matching the components were observed. Both the raters were trained in BMAT and IMS mobility assessment methods with the assistance of demo videos and with practice. The strength of the study was that the raters involved in the pilot study were different to those who participated in the final study. It indicates that both the scales were easy to understand and can be used by other healthcare workers as they facilitate good interdisciplinary communication and decisions on patients’ outcomes, recovery and can encourage mobility. During the mobility assessment, the marching component of BMAT was difficult to assess in patients with lower limb fractures stabilized surgically due to external fixators or weight bearing restrictions. But the assessments were completed in safe mode using assistive devices. The research demonstrated excellent agreement between the two raters for BMAT and between the BMAT and IMS. The reason for the high agreement could be prior training, matching of the components and the type of sampling.

Limitations of the study

Study was conducted in a single setting. The components of BMAT and IMS were not having exact matches. More than two components matched to one component of BMAT requiring the expertise opinion to match the components. This study included only physiotherapists and no other healthcare workers.

Bedside Mobility Assessment Tool is a quick and novel tool to assess mobility of inpatients from bedside to ambulation stage. It will help the physiotherapists make quick decisions on patients’ mobility, recovery and can encourage mobility by providing appropriate assistive devices. Physiotherapists and other healthcare team can have interdisciplinary communication on mobility status of inpatients with ease since BMAT is quick and easy to use.

BMAT can be validated by including other healthcare workers.

Conclusion

Bedside Mobility Assessment Tool (BMAT) is a valid scale for use in an acute orthopedic setting and can be recommended to be used by physiotherapists, nurses and other healthcare workers.

Conflict of interest

Nil