TY - JOUR
T1 - The Northwick Park Therapy Dependency Assessment scale
T2 - a psychometric analysis from a large multicentre neurorehabilitation dataset
AU - Alexandrescu, Roxana
AU - Siegert, Richard
AU - Turner-Stokes, Lynne
PY - 2015
Y1 - 2015
N2 - Purpose: To assess the internal reliability, construct and concurrent validity and responsiveness of the Northwick Park Therapy Dependency Assessment (NPTDA) scale. Method: A cohort of 2505 neurorehabilitation patients submitted to the UK Rehabilitation Outcomes Collaborative database. Cronbach’s coefficient-α was used to assess internal reliability and factor analysis (FA) to assess construct validity. We compared NPTDA scores at admission and discharge to determine responsiveness. Results: Coefficient-α for the whole scale was 0.74. The exploratory FA resulted in a four-factor model (Physical, Psychosocial, Discharge planning and Activities) that accounted for 43% of variance. This model was further supported by the confirmatory FA. The final model had a good fit: root-mean-square error of approximation of 0.069, comparative fit index/Tucker–Lewis index of 0.739/0.701 and the goodness of fit index of 0.909. The NPTDA scores at admission and discharge were significantly different for each of the factors. Expected correlations were seen between the admission scores for the NPTDA, the Rehabilitation Complexity Scale (r = 0.30, p < 0.01) and the Functional Independence Measure (r = −0.25, p < 0.01). Conclusions: The scale demonstrated acceptable internal reliability and good construct and concurrent validity. NPTDA may be used to describe and quantify changes in therapy inputs in the course of a rehabilitation programme.
AB - Purpose: To assess the internal reliability, construct and concurrent validity and responsiveness of the Northwick Park Therapy Dependency Assessment (NPTDA) scale. Method: A cohort of 2505 neurorehabilitation patients submitted to the UK Rehabilitation Outcomes Collaborative database. Cronbach’s coefficient-α was used to assess internal reliability and factor analysis (FA) to assess construct validity. We compared NPTDA scores at admission and discharge to determine responsiveness. Results: Coefficient-α for the whole scale was 0.74. The exploratory FA resulted in a four-factor model (Physical, Psychosocial, Discharge planning and Activities) that accounted for 43% of variance. This model was further supported by the confirmatory FA. The final model had a good fit: root-mean-square error of approximation of 0.069, comparative fit index/Tucker–Lewis index of 0.739/0.701 and the goodness of fit index of 0.909. The NPTDA scores at admission and discharge were significantly different for each of the factors. Expected correlations were seen between the admission scores for the NPTDA, the Rehabilitation Complexity Scale (r = 0.30, p < 0.01) and the Functional Independence Measure (r = −0.25, p < 0.01). Conclusions: The scale demonstrated acceptable internal reliability and good construct and concurrent validity. NPTDA may be used to describe and quantify changes in therapy inputs in the course of a rehabilitation programme.
U2 - 10.3109/09638288.2014.998779
DO - 10.3109/09638288.2014.998779
M3 - Article
SN - 0963-8288
JO - Disability and Rehabilitation
JF - Disability and Rehabilitation
ER -