Inter- and intra-tester reliability of the acute brain injury physiotherapy assessment (ABIPA) in patients with acquired brain injury

Background: The Acute Brain Injury Physiotherapy Assessment (ABIPA) is a new outcome measure with face validity and sensitivity to change in the early stages of neuromotor recovery after acquired brain injury (ABI). Reliability of physiotherapists using the tool has not been established. Objective: Determine inter- and intra-tester reliability of physiotherapists using the ABIPA. Methods: An observational study using video-recorded assessments of patient performance (n = 7) was undertaken with two cohorts of physiotherapists: those receiving training (n = 23) and those provided with guidelines only (n = 7) to administer the ABIPA. Results: Across all physiotherapists (n = 30), inter-tester reliability was excellent (α ≥ 0.9) for total ABIPA score. All individual items, except trunk alignment in supine (α = 0.5), showed excellent or good internal consistency (α ≥ 0.7). For intra-tester reliability, substantial or perfect agreement was achieved for eight items (weighted Kappa Kw ≥ 0.6), moderate agreement for four items (Kw = 0.4–0.6) and three items achieved fair agreement (alignment head supine: Kw = 0.289; alignment trunk supine: Kw = 0.387 and tone left upper limb: Kw = 0.366). Conclusion: Physiotherapists are highly consistent using the ABIPA but several items may need revision to improve intra-tester reliability.