Development and test-retest reliability assessment of a low-cost, 3D printed tool for assessing different aspects of hand dexterity

Abstract

Background: Hand dexterity assessments related to fine motor movements are routinely administered in clinical settings to ascertain an individual's hand function. However, to perform a detailed assessment multiple devices are needed which can be time-consuming and costly to administer.

Purpose: We designed and assessed the test-retest reliability of a 3D printed dexterity device in a cohort of healthy young adults and community-dwelling older adults. This study examines the reliability of the device, association between perceived fine motor gripping and manipulation dexterity components, and dominant hand outperformance during both tasks.

Study design: Test-retest study of a clinical measurement tool.

Methods: A convenience sample of thirty-six healthy community-dwelling older and young adults was included in our study. The device was used to collect data at two testing sessions to establish test-retest reliability. Fine motor manipulation dexterity was assessed by lifting notched pegs over a vertical barrier and inserting them into randomly oriented holes sequentially. Fine motor gripping dexterity was assessed by taking these notched pegs out of the holes, lifting them over the barrier and dropping them into a large container.

Results: Intraclass correlation coefficient (ICC)_2,1 showed good to excellent test-retest reliability on the dominant and nondominant hands when using the device. Only modest association was found within-hand for the gripping versus manipulation dexterity tests. The between-hand motor gripping dexterity test demonstrated a strong association; however, between-hand the motor manipulation dexterity test was only moderately associated.

Conclusion: The device was reliable, discriminated between the motor gripping and motor manipulating dexterity tasks, and was sensitive to handedness during the motor manipulating dexterity task. It shows promise as a hand dexterity assessment device which may provide efficiency and cost advantages. It is freely available via http://www.rehabtools.org/dexterity.html.

Keywords: 3D print; Dexterity; Fine motor; Gross motor; Handedness; Pegboard.