Date Presented 03/26/20
The purpose of this study was to determine the average change score on the VMI that would represent a clinically important change in functional skills. Anchor-based methods were used to compare VMI change scores to Likert scale ratings of children’s performance in fine-motor tasks, handwriting, and activities of daily living. Results indicated that children with improvements in functional skills had VMI scores that declined. These findings question the utility of VMI scores as indicators of progress in children.
Primary Author and Speaker: Alisha Ohl
Additional Authors and Speakers: David Schelly
Contributing Authors: Shari Sharpe
PURPOSE: According to practice trend surveys, the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI; Beery & Beery, 2010) has been one of the most commonly used assessments by pediatric occupational therapists for the past 30 years (Burtner et al., 2002; Crowe, 1989). The VMI, which requires the examinee to copy a series of progressively more complex shapes, is a standardized assessment that can be used to determine progress in the integration of visual and motor abilities. While increasing scores that surpass the standard error of measurement (SEM) are evidence of improvements on the VMI, it is unknown what these improvements translate to in functional terms. For example, it is unclear what a 10- or 15-point improvement in VMI scores relates to in a child’s daily life, as opposed to a 1- or 5-point improvement. The purpose of this study was to determine the average change score on the VMI that would correspond to a clinically important change in functional activities, known as the minimal clinically important difference (MCID; for a review, see Copay et al., 2007). The following research question guided this study: What is the average improvement score on the VMI that corresponds with clinically important changes in the handwriting, fine-motor, and activity of daily living (ADL) skills of children?
DESIGN AND METHOD: This quantitative psychometric study used anchor-based methods to estimate the MCID of the VMI in children receiving school-based occupational therapy services. The following data were collected by 3 occupational therapists working in a public school system in the Northeastern United States: 1) child demographic information, 2) pre- and post-test scores on the VMI (at the beginning and end of one school year), and 3) occupational therapist responses to a 15-point Likert scale measuring the magnitude of change in the children’s fine-motor, handwriting, and ADL function at the end of the school year. The 15-point Likert scale was used in response to the following question: “Compared to the beginning of the school year, has there been any functional change in the child’s ability to perform [fine-motor/handwriting/ADL] tasks?” The Likert choices ranged from -7 (a very great deal worse) to +7 (a very great deal better). Children were classified as having experienced a minimal clinically important change if their Likert rating fell within the ranges +2 or +3 (a little better orsomewhat better). Data were analyzed by calculating the mean change score on the VMI for the children who experienced a minimal clinically important positive change.
RESULTS: Data were gathered for 74 children, the majority of which were male (80.6%) and ranged in age from 5 to 16 years (M= 8.5, SD= 2.7). The average VMI pre score was 78.3 (SD= 13.2) and the average post-score was 77.0 (SD= 14.0). Approximately half of the children had change scores within the SEM for the VMI (+/-5 points). For children with minimal clinically important improvements in fine-motor skills, their average VMI change score was -2.78 (CI = -10.0∼4.5), for minimal improvements in handwriting, the average VMI change score was -1.56 (CI = -8.0∼4.8), and for minimal improvements in ADLs, the average VMI change score was -2.04 (CI = -9.0∼4.9).
CONCLUSION: We were unable to determine the MCID for the VMI. Despite experiencing slight declines in VMI scores on average, the children rated in this study still experienced functional improvements in handwriting, fine-motor, and ADL skills. This finding is possibly the result of a small sample size, or alternatively, highlights the limits of the VMI, in that it was not designed to detect functional changes in children. These results beg the question: Why are we using the VMI to chart progress in therapy?
References
Copay, A. G., Subach, B. R., Glassman, S. D., Polly Jr, D. W., & Schuler, T. C. (2007). Understanding the minimum clinically important difference: a review of concepts and methods. The Spine Journal, 7(5), 541-546.
Beery, K.E., & Beery, N.A. (2010). Beery VMI: Administration, Scoring, and Teaching Manual. Bloomington, MN: PsychCorp.
Burtner, P. A., McMain, M. P., & Crowe, T. K. (2002). Survey of occupational therapy practitioners in southwestern schools: Assessments used and preparation of students for school-based practice. Physical & Occupational Therapy in Pediatrics, 22(1), 25-39.
Crowe, T. K. (1989). Pediatric assessments: A survey of their use by occupational therapists in northwestern school systems. The Occupational Therapy Journal of Research, 9(5), 273-286.
