Is the Test of Visual Motor Integration an Effective Outcome Measure for Handwriting Interventions?

SIGNIFICANCE: The purpose of this study was to determine whether a widely used assessment of visual motor skills, the Test of Visual Motor Integration (VMI), is appropriate for use as an outcome measure for handwriting interventions. There are numerous reports in the literature documenting significant correlations between handwriting and visual–motor coordination (Cornhill & Case-Smith, 1996). The VMI is a commonly used measure to determine eligibility for occupational therapy services. More recently, authors have begun to use the VMI not just as a screening or assessment tool but as an outcome measure in an attempt to measure improvements in visual–motor integration skills following handwriting interventions (Howe, Roston, Sheu, & Hinojosa, 2013). It is important to determine whether this use of the VMI is appropriate.

METHOD: Participants were 207 kindergarten through second-grade students enrolled in two regular education public school districts. The study was completed in a total of 12 classrooms in the northeast part of the United States. A two-group, pretest–posttest design was implemented. One school used a randomized assignment of classrooms, whereas the other school used a convenience assignment due to teacher availability. The outcome measures were administered to participants at pretest and posttest. The Test of Handwriting Skills—Revised (THS–R), the Minnesota Test of Handwriting Skills (MHA), and the VMI were administered. The Size Matters Handwriting Program (SMHP) was implemented in 20-min sessions, 5 days per week, by the classroom teacher with occupational therapist (OT) consultation within each intervention classroom until 40 sessions were completed. The control group did not receive the SMHP instruction or any materials during the study but had access to them after completion of data collection. Within-group differences over time were assessed with paired t tests. Independent-samples t tests were used to compare the groups on the changes between their postintervention and preintervention scores on the measures. Cohen’s d was calculated to determine effect sizes. Pearson product-moment correlation coefficients were used to correlate pretest VMI with handwriting measure scores both by grade and total obtained sample.

RESULTS AND CONCLUSION: Results show moderate significant correlations between the VMI and the handwriting measures on pretest scores (r = .32, p = .01), which is consistent with findings from previous studies. The intervention group demonstrated significant improvements on the handwriting measures on change scores from pretest to posttest, with medium to mostly large effect sizes. There were no significant changes in the change scores on the VMI (t = 1.19, p = .23). Results suggest that the VMI is not an appropriate outcome measure for handwriting interventions, as it may not detect the changes in handwriting related to OT intervention. Literature consistently supports some level of correlation between the VMI and handwriting, which lends support for the cautious use of the VMI as a screening tool to help determine which children would benefit from further assessment and treatment.

References

Cornhill, H., & Case-Smith, J. (1996). Factors that relate to good and poor handwriting. American Journal of Occupational Therapy, 50, 732–739. http://dx.doi.org/10.5014/ajot.50.9.732

Howe, T.-H., Roston, K. L., Sheu, C.-F., & Hinojosa, J. (2013). Assessing handwriting intervention effectiveness in elementary school students: A two-group controlled study. American Journal of Occupational Therapy, 67, 19–26. http://dx.doi.org/10.5014/ajot.2013.005470