The reliability, validity and feasibility of tools used to screen for caregiver burden: a systematic review

The overall objective of this review is to quantitatively measure the psychometric properties and the feasibility of caregiver burden screening tools. The more specific objectives were to determine the reliability, validity as well as feasibility of tools that are used to screen for caregiver burden and strain.

This review considered international quantitative research papers that addressed the psychometric properties and feasibility of caregiver burden screening tools.

The search strategy aimed to find both published and unpublished studies from 1980-2007 published only in the English language. An initial limited search of MEDLINE and CINAHL was undertaken followed by analysis of the text words contained in the title and abstract and the index terms used to describe the article. A second search identified keywords and index terms across major databases. Third, the reference list of identified reports and articles was searched for additional studies.

Each paper was assessed by two independent reviewers for methodological quality prior to inclusion in the review using an appropriate critical appraisal instrument from the Joanna Briggs Institutes' System for the Unified Management, Assessment and Review (SUMARI) package.

Because burden is a multidimensional construct defined internationally with a multitude of other terms, only those studies whose title, abstract or keywords contained the search terminology developed for this review were identified for retrieval.

The construct of caregiver burden is not standardized, and many terms are used to describe burden. A caregiver is also identified as a carer. Instruments exist in multiple languages and have been tested in multiple populations. A total of 112 papers, experimental and non-experimental in nature, were included in the review. The majority of papers were non-experimental studies that tested or used a caregiver burden screening tool. Because of the nature of these papers, a meta-analysis of the results was not possible. Instead a table is used to depict the 74 caregiver burden screening tools that meet the psychometric and feasibility standards of this review. The Zarit Burden Interview (ZBI), in particular the 22-item version, has been examined the most throughout the literature. In addition to its sound psychometric properties, the ZBI has been widely used across languages and cultures.

The significant amount of research that has already been done on psychometric testing of caregiver burden tools has provided a solid foundation for additional research. Although some tools have been well tested, many tools have published limited psychometric properties and feasibility data. The clinician needs to be aware of this and may need to team up with a researcher to obtain additional research data on their specific population before using a minimally tested caregiver burden screening tool. Because caregiver burden is multidimensional and many different terms are used to describe burden, both the clinician and researcher need to be precise in their selection of the appropriate tool for their work.