A psychometric analysis of the Needs Assessment Checklist (NAC)

Abstract

Design: Consecutive series, psychometric validation study. Objective: To evaluate the psychometric reliability and validity of a clinically focused measure of rehabilitation outcome, known as the Needs Assessment Checklist (NAC). Setting: Tertiary care, spinal cord injury centre (National Spinal Injuries Centre), Stoke Mandeville Hospital, UK. Participants: In total, 43 spinal cord injured (SCI) in-patients (38 male and five female). During this study all patients actively participated in a comprehensive, multidisciplinary Goal Planning and Needs Assessment Rehabilitation Programme. Intervention: Test-retest and concurrent assessment, conducted in one administration, within a week of routine clinical assessment. Reliability analyses were performed examining the NAC's internal consistency, test-retest reliability, and concurrent validity. Main outcome measures: The NAC is a rehabilitation outcome measure, specifically developed for the SCI population, which is used to assess patient attainment in core rehabilitation areas at mobilisation and prior to discharge. The Spinal Cord Independence Measure (SCIM) and Hospital Anxiety and Depression Scale (HADS) were also employed as comparable benchmark assessment measures with established psychometric properties. Patient comments were gained during this administration, rating the NAC with regard to its usefulness, clarity, and personal relevance. Results: Reliability analyses yielded high internal consistency coefficients (mean α=0.8587, SD=0.918). All subscales performed above the specified level (0.7). The mean item-internal validity, correlation for NAC subscales was 0.5921 (SD=0.1411). Test-retest correlations ranged between 0.694 (Bladder Management) and 0.904 (Skin Management) (P≤0.01). The mean percentage of agreement between clinical and test-retest assessment over all NAC subscales was 75.5% (SD=5.01%). Concurrent validity analyses correlating individual subscale scores with SCIM and HADS subscales produced high correlations between 0.850 (Activities of Daily Living with SCIM Self-Care, P≤0.01) and -0.466 (Psychological Issues with HADS-Depression, P≤0.01). Significant differences were identified between injury category within NAC subscales; however, this was not consistent. The NAC achieved high patient ratings, attaining mean ratings of seven (out of 10) for usefulness, and eight for its clarity and personal relevance. Conclusion: The findings of this study indicate that the NAC is a psychometrically reliable and valid clinical measure of rehabilitation outcome.