Abstract
Background and Purpose: Fall-risk screening instruments have been underutilized in clinical settings because of their lengthy administration time, need of cumbersome equipment, and lack of validation. The primary objective of this study was to assess the validity (sensitivity and specificity) of the Minimal Chair Height Standing Ability Test (MCHSAT). The secondary objective was to develop guidelines to provide physical therapists with best-practice recommendations that can easily be implemented in clinical practice.
Methods: A retrospective cohort study design was used in which falling history, major medical conditions, cognitive status (Mini-Mental State Examination), and level of independence (Independent Activities of Daily Living) were obtained for 167 community-dwelling older adults (mean age = 83.6 +/- 7.3 years), residents of British Columbia, Canada. Participants MCHSAT performance was assessed using a chair whose seat height was modifiable by increments of 5 cm, starting at 47 cm and lowering after each successful attempt. Sensitivity and specificity of the MCHSAT at each chair height were calculated and plotted as a receiver operating characteristic curve. A model to identify participants with history of falls was developed using a forward logistic regression (Wald).
Results: Mean MCHSAT performance (cm) was significantly better for participants without history of falls (30.3 cm, 95% CI: 28.1-32.5 cm) than for those with history of falls (37.7 cm, 95% CI: 35.5-40.0 cm) and was the single risk factor associated with fall status ([beta]= 1.087, P < .001). The optimal MCHSAT performance for identifying participants with history of falls was 34 cm (AUC = 0.72, 95% CI: 0.63-0.82). At this threshold, sensitivity and specificity values were 75% and 62%, respectively.
Discussion: Using 34 cm as the optimal performance, the MCHSAT correctly identified 75% of participants with history of falls and 62% of participants without history of falls. This provides evidence that the MCHSAT is a valid screening tool for use with an older Canadian population.
Conclusion: As a simple and inexpensive testing instrument, the MCHSAT has potential to enhance the care of our elderly population, improve an understanding of patients' fall-risk status, and substantially reduce fall-related costs to the health care system.