Peter Hagell1, Anette Alvariza2, Albert Westergren3, Kristofer Årestedt4. 1. The PRO-CARE Group, School of Health and Society, Kristianstad University, Kristianstad, Sweden. Electronic address: Peter.Hagell@hkr.se. 2. Department of Health Care Sciences and Palliative Research Centre, Ersta Sköndal University College, Stockholm, Sweden; Capio Palliative Care Unit, Stockholm, Sweden. 3. The PRO-CARE Group, School of Health and Society, Kristianstad University, Kristianstad, Sweden. 4. Department of Health Care Sciences and Palliative Research Centre, Ersta Sköndal University College, Stockholm, Sweden; Department of Health and Caring Science, Linnaeus University, Kalmar, Sweden; Kalmar County Hospital, Kalmar, Sweden.
Abstract
CONTEXT: Previous studies have supported the psychometric properties of the 22-Item Zarit Burden Interview (ZBI-22) scale among family caregivers of people with various disorders, including Parkinson's disease (PD). However, its short forms have not been psychometrically tested among PD family caregivers, and available psychometric analyses have not accounted for the ordinal nature of item-level data. OBJECTIVES: To assess the psychometric properties of the ZBI-22 and its short forms among family caregivers of people with PD, while taking account for the ordinal nature of data. METHODS: Cross-sectional postal survey ZBI-22 data from 66 family caregiver members (59% women; mean age 69.6 years) of a local Swedish PD society branch were analyzed according to classical test theory methods based on polychoric/polyserial correlations. RESULTS: Missing item responses were ≤ 5%. Corrected item-total correlations were ≥ 0.42 and floor/ceiling effects were <20%, besides for the briefest (4- and 1-item) short forms (20% and 40% floor effects, respectively). Reliability was good for all scales (ordinal alpha 0.89-0.95). External construct validity was in general accordance with a priori expectations. Short forms demonstrated good criterion-related validity (rs 0.87-0.99) and discriminative ability (area under the curve, 0.91-0.98) relative to the full ZBI-22. CONCLUSION: This study provides support for the reliability and validity of the ZBI-22 and its various short forms for use among PD family caregivers. In studies where caregiver burden is a central outcome, either ZBI-22 or ZBI-12 is suggested for use; other short forms can be used when caregiver burden is of less central focus or for clinical screening.
CONTEXT: Previous studies have supported the psychometric properties of the 22-Item Zarit Burden Interview (ZBI-22) scale among family caregivers of people with various disorders, including Parkinson's disease (PD). However, its short forms have not been psychometrically tested among PD family caregivers, and available psychometric analyses have not accounted for the ordinal nature of item-level data. OBJECTIVES: To assess the psychometric properties of the ZBI-22 and its short forms among family caregivers of people with PD, while taking account for the ordinal nature of data. METHODS: Cross-sectional postal survey ZBI-22 data from 66 family caregiver members (59% women; mean age 69.6 years) of a local Swedish PD society branch were analyzed according to classical test theory methods based on polychoric/polyserial correlations. RESULTS: Missing item responses were ≤ 5%. Corrected item-total correlations were ≥ 0.42 and floor/ceiling effects were <20%, besides for the briefest (4- and 1-item) short forms (20% and 40% floor effects, respectively). Reliability was good for all scales (ordinal alpha 0.89-0.95). External construct validity was in general accordance with a priori expectations. Short forms demonstrated good criterion-related validity (rs 0.87-0.99) and discriminative ability (area under the curve, 0.91-0.98) relative to the full ZBI-22. CONCLUSION: This study provides support for the reliability and validity of the ZBI-22 and its various short forms for use among PD family caregivers. In studies where caregiver burden is a central outcome, either ZBI-22 or ZBI-12 is suggested for use; other short forms can be used when caregiver burden is of less central focus or for clinical screening.
Authors: Matthias Seibl-Leven; Christian von Reeken; Roland Goldbrunner; Stefan Grau; Maximilian Ingolf Ruge; Norbert Galldiks; Veronika Dunkl; Martin Kocher; Raymond Voltz; Heidrun Golla Journal: J Neurooncol Date: 2018-02-20 Impact factor: 4.130
Authors: Elliottnell Perez; Paul B Perrin; Sarah K Lageman; Teresita Villaseñor; Joseph M Dzierzewski Journal: Disabil Rehabil Date: 2020-09-11 Impact factor: 2.439