Linguistic validation and reliability properties are weak investigated of most dementia-specific quality of life measurements-a systematic review

Abstract

Objective: For people with dementia, the concept of quality of life (Qol) reflects the disease's impact on the whole person. Thus, Qol is an increasingly used outcome measure in dementia research. This systematic review was performed to identify available dementia-specific Qol measurements and to assess the quality of linguistic validations and reliability studies of these measurements (PROSPERO 2013: CRD42014008725).

Study design and setting: The MEDLINE, CINAHL, EMBASE, PsycINFO, and Cochrane Methodology Register databases were systematically searched without any date restrictions. Forward and backward citation tracking were performed on the basis of selected articles.

Results: A total of 70 articles addressing 19 dementia-specific Qol measurements were identified; nine measurements were adapted to nonorigin countries. The quality of the linguistic validations varied from insufficient to good. Internal consistency was the most frequently tested reliability property. Most of the reliability studies lacked internal validity.

Conclusion: Qol measurements for dementia are insufficiently linguistic validated and not well tested for reliability. None of the identified measurements can be recommended without further research. The application of international guidelines and quality criteria is strongly recommended for the performance of linguistic validations and reliability studies of dementia-specific Qol measurements.

Keywords: Dementia; Linguistic validation; Psychometric properties; Quality of life; Reliability; Systematic review.