Development, validation, reliability and predictive capacity of neuro-motor recovery of the Acute Brain Injury Physiotherapy Assessment (ABIPA): A tool for physiotherapists during early management of people following Acquired Brain Injury (ABI).

In the acute stages following ABI, when people are functionally dependent, a specific scale for physiotherapists to monitor incremental changes in neuro-motor function is needed. This thesis represents the development of the acute brain injury physiotherapy assessment (ABIPA), an outcome measure to fill this gap. The first step in the development of the ABIPA was to identify items known to reflect acute neuro-motor impairments for inclusion in the measure and develop scoring criteria along with guidelines for the identified items (Study 1). The final items of the ABIPA were: upper limb and lower limb movement; overall muscle tone in each limb; head and trunk alignment in supine; head and trunk alignment in sitting; head and trunk control in sitting; and overall presentation. Once items were selected and scoring criteria established, the new outcome measure underwent psychometric testing. In Study 1 responsiveness and concurrent validity of the ABIPA were examined together with participants assessed at day 1, 3, 7 and at discharge through their acute hospital admission to capture clinical changes. Concurrent validity of the ABIPA was examined against other commonly used measures; specifically, the Glasgow Coma Scale (GCS), Clinical Outcomes Variable Scale (COVS) and Motor Assessment Scale (MAS). The ABIPA was found to be responsive to change demonstrating greater sensitivity to change (SRM = 0.83) when compared to other assessment measures (SRMs ≤ 0.77) during the early weeks following ABI. Additionally, the ABIPA demonstrated good concurrent validity with commonly used measures to assess acute brain injury, including the GCS (rho = 0.76, p ≤ 0.001, COVS (rho = 0.82, p ≤ 0.001) and MAS (rho = 0.66, p ≤ 0.001). Study 2 of this thesis investigated inter- and intra-tester reliability of physiotherapists using the ABIPA. An observational study using video-recorded ABIPA assessments of seven people with moderate or severe ABI was undertaken with two cohorts of physiotherapists; trained and untrained. Trained physiotherapists attended two one-hour training sessions; an initial instructional session and then a practice session. The untrained physiotherapists were provided with the ABIPA guidelines. Participating physiotherapists scored the video recorded package of ABIPA assessments with intra-tester reliability examined by repeat screenings of the video recorded assessments a minimum of two weeks after the initial session. A high level of inter-tester reliability (α ≥ 0.9) was demonstrated for both trained and untrained physiotherapists. Trained physiotherapists showed good to excellent internal consistency for total ABIPA score and for all individual items except for alignment of the trunk in supine (α = 0.4). Similarly, untrained physiotherapists showed good to excellent internal consistency on the total ABIPA score and all individual items except for alignment of the trunk in supine (α = 0.09) and alignment of the head in supine (α = 0.60). For intra-tester reliability, substantial or perfect agreement was achieved for eight items (Weighted kappa Kw ≥ 0.6), with moderate agreement reached for a further four items (Kw = 0.4 - 0.6), leaving three items (representing 20% of the scale) achieving fair agreement. Items with the lowest agreement were alignment of the head in supine (Kw = 0.289); alignment of the trunk in supine (Kw = 0.387) and tone left upper limb (Kw = 0.366). This was similar for both the trained and untrained physiotherapists. Study 3 of the thesis investigated the underlying factor structure of the ABIPA using an exploratory factor analysis with principal axis factor extraction and varimax rotation. A four-factor solution with a simple structure (factor loadings ≥.30) that explained 69.6% of total variance was suggested. Factor one (alignment and posture) accounted for 36.6% of the variance while factor two (tone) explained 15.8%, factor three (left side movement) explained 9.6% and factor four (right side movement) accounted for 7.5%. Two items were identified with the lowest loading with the four-factor solution, alignment of the head in supine loading to factor three at 0.358 and alignment of the trunk in supine loading to factor two at 0.405. The final study of this thesis examined the association of the ABIPA with long term recovery following ABI by evaluating ABIPA scores at acute hospital admission and ABIPA scores at admission to rehabilitation against: length of stay in the acute hospital setting, length of stay in rehabilitation, discharge destination and secondary measures including the GCS, Mental Status Questionnaire, COVS, Coma Recovery Scale-Revised (CRS-R), Functional Independence Measure (FIM), Disability Rating Scale (DRS) and Carer Strain Index (CSI). ABIPA at acute hospital admission and rehabilitation were inversely related to acute, rehabilitation and total hospital length of stay (rho ≥ -.508; p ≤ 0.044). ABIPA at acute hospital admission demonstrated moderate to good correlations with ABIPA, FIM (motor) and COVS (rho ≥ 0.563, p ≤ 0.023) at long term follow up. ABIPA scores at rehabilitation admission demonstrated moderate to good correlations with GCS and MSQ (rho ≥ 0.564, p ≤ 0.023) and excellent correlations with ABIPA, FIM (motor) and COVS (rho ≥ 0.799, p ≤ 0.001). Overall the ABIPA showed moderate to good relationships with length of stay and long-term neuro-motor recovery from severe ABI. This thesis demonstrates that a new outcome measure with strong psychometric properties has been developed for measurement of acute neuro-motor impairments following severe ABI. Further investigation is required to continue the development paradigm by removing outlying items, establishing a minimal clinically important difference and expanding participant numbers.