Reliability of a U.S. Version of the Nottingham Sensory Assessment

PURPOSE: The purpose of this study was to develop a U.S. version of the Nottingham Sensory Assessment (NSA) and evaluate the interrater reliability to make a reliable, multimodal sensory impairment measure available to U.S. occupational therapists.

RATIONALE: Many stroke survivors experience sensory deficits, yet there is currently no gold standard reliable standardized assessment used by clinicians in the United States. The NSA is an established standardized multimodal assessment used with patients poststroke in other countries. Research has shown that occupational therapists perform and value information gained from sensory measures, but few therapists use standardized multimodal measures in practice.

DESIGN: This was a quantitative prospective study evaluating the interrater reliability of a modified version of the NSA suitable for use with American stroke survivors.

PARTICIPANTS: The authors recruited 17 persons with chronic stroke (i.e., ≥6 mo poststroke) to act as patient participants. This study employed 6 licensed rehabilitation therapists and 1 researcher as assessor participants. Patient and assessor participants were associated with a university onsite clinic.

METHOD: A U.S. version of the NSA was created by standardizing the materials, adjusting the administration instructions and scoring sheet, and incorporating the outcomes of previous research on NSA subtests. Changes to previous versions of the NSA’s content and language were made through regular discussions among the authors and piloting the US–NSA with occupational therapy students and expert clinicians. The US–NSA includes four subtests: Tactile Sensation, Sharp–Dull Discrimination, Proprioception, and Stereognosis; together, these subtests assess a broad range of sensory detection and discrimination on the upper and lower limbs. Scores are summed for each subtest to provide a composite score for each extremity; scores for each extremity range from 0–8 or 0–12 (Stereognosis). Patient participants were assessed by two different assessors, who remained blind to the results, between 1 and 8 days apart.

ANALYSIS: The authors used intraclass correlation coefficients (ICCs) to analyze the interrater reliability of the subtests. The ICCs were interpreted as follows: ICC < .40, weak agreement; ICC between .40 and .75, moderate agreement; and ICC > .75, strong agreement.

RESULTS: The final patient sample consisted of 17 chronic stroke patients who were an average of 5 yr poststroke. The final assessor sample included 7 assessor participants, predominantly occupational therapists and female. The findings indicate strong agreement for most test items (rs = .772–.939), except for the Sharp–Dull Discrimination item on the lower extremity with moderate agreement (r = .496). This suggests that the US–NSA has been modified successfully and retains interrater reliability.

DISCUSSION: The US–NSA is a promising sensory impairment assessment available for use by U.S. occupational therapists to inform intervention planning, measuring outcomes, and quality of care. The US–NSA and its training materials will be freely available for clinicians to access and learn to administer the measure independently.

IMPACT STATEMENT: These results suggest that the US–NSA is a viable standardized measure that may allow occupational therapists to understand the nature of clients’ sensory impairments in order to address these deficits in rehabilitation and potentially enhance functional outcomes. In addition, this measure can be used to support research and demonstrate occupational therapy outcomes.