Date Presented 3/31/2017
This study examines the use of a performance-based assessment to detect functional hand deficits in persons with schizophrenia. The Jebsen Hand Function Test may have value as an objective measure of hand function in this population, allowing occupational therapists to provide more comprehensive treatment.
Primary Author and Speaker: Alice Jih
Additional Authors and Speakers: Myra Branch, Michaela Fraser, Heesun Jung, Brooke Morgan
Contributing Authors: Dawn M. Nilsen, Elaine Mullen, Sharon Gutman
PURPOSE: This study examines whether a performance-based assessment of hand function, the Jebsen Hand Function Test (JHFT), is sensitive enough to identify hand motor impairments and has convergent validity with the Purdue Pegboard Test (PPBT), a measure that has previously identified hand motor impairments in adults with schizophrenia.
BACKGROUND: There is a growing body of evidence demonstrating that global motor deficits may be common in adults with schizophrenia secondary to impairments in brain areas associated with motor control (e.g., basal ganglia, cerebellum) and that these deficits may impact engagement in occupation. Although motor impairments are not commonly addressed in the treatment of this population, they may adversely impact cognitive and perceptual processing. For example, impairments in fine motor control may result in an inability to manipulate coins when attempting to make change during grocery shopping, which may further exacerbate stress levels in social situations, thereby causing further decline in cognitive skills. The purpose of this study was to determine if a performance-based measure of hand function could identify subtle hand motor deficits not commonly assessed in this population but adversely impacting daily life function.
DESIGN: This was a pilot study designed to determine the convergent validity of the JHFT by identifying functional hand deficits that had first been identified with the PPBT, an impairment-based measure of dexterity that has established validity with this population. A convenience sample of 10 participants was evaluated by the treating therapist at a continuing day treatment program. Participants were over age 18, were diagnosed with schizophrenia or schizoaffective disorder, and had cognitive function sufficient to complete both the PPBT and JHFT. Those with tardive dyskinesia or other documented movement disorders were excluded.
METHOD: The treating therapist was trained in the standardized administration of the PPBT and JHFT. One trial of the PPBT was administered, followed immediately by JHFT administration. PPBT scores were analyzed to identify participants who scored more than two standard deviations below norms, indicating hand motor deficits. JHFT scores were also compared to established norms to determine whether performance-based hand motor deficits existed. Convergent validity was assessed using the Pearson product–moment correlation.
RESULTS: Seventy percent of participants scored greater than two standard deviations below the norm on all PPBT subtests, and 60% did on all JHFT subtests, suggesting impairments in dexterity and performance-based hand function. All of the JHFT subtests were correlated with the right + left + both subtest of the PPBT (rs =.50–.90, with five correlations significant at p < .04), suggesting moderate to high convergent validity between the PPBT and JHFT.
DISCUSSION: The results of the study suggest the JHFT can be used to identify functional hand deficits in adults with schizophrenia.
IMPACT STATEMENT: The results support previous literature suggesting that motor impairments may be part of a global syndrome in this population. Clinicians should consider routinely screening for motor deficits because such deficits may interact with cognitive and perceptual processing skills impacting occupational engagement.
References
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