Measuring quality of life in Dutch people with aphasia: development and psychometric evaluation of the SAQOL-39NL

ABSTRACT

Background: Cross-cultural adaptation of health-related quality of life (HRQL) scales is useful as it allows comparisons of therapy outcomes across different countries to be drawn.

Aims: To adapt the English Stroke and Aphasia Quality of Life—39 item generic stroke scale (SAQOL-39g) into Dutch. To investigate the psychometric properties (acceptability, internal consistency, test–retest reliability and construct validity) of the Dutch version (SAQOL-39NL).

Methods & Procedures: Established guidelines for cross-cultural adaptation of self-report measures were followed. Individuals with chronic aphasia were recruited from six centres in The Netherlands. Participants completed the SAQOL-39NL and a visual analogue scale on HRQL in an interview format with an aphasia specialist speech and language therapist.

Outcomes & Results: The cross cultural adaptation resulted in a consensus version of the SAQOL-39NL, which participants (n = 13) felt was informative and of value in assessing the impact of stroke on their lives. The SAQOL-39NL was acceptable (no missing data; no floor or ceiling effects) to people with chronic aphasia (n = 47). Internal consistency (Cronbach’s alpha = 0.89 for scale; 0.84–0.91 for domains) and test–retest reliability were excellent (ICC = 0.90 for scale, 0.70–0.93 for domains). Internal validity (moderate intercorrelations between domains) and convergent validity (r = 0.45) were good.

Conclusions: The SAQOL-39NL is a psychometrically sound measure of HRQL for Dutch speaking people with aphasia. As is common with new measures, its psychometric properties need to be evaluated further; and its appropriateness as a clinical outcome measure needs to be determined. Yet, the SAQOL-39NL is a promising new measure for use in clinical practice, audit and research.

KEYWORDS:

• Quality of life
• SAQOL-39
• outcome measures

Acknowledgements

We are very grateful to all participating aphasia centres and the aphasic participants, and the bachelor SLT students at the HU University of Applied Sciences who were involved in the first stages of the development of this instrument.

Disclosure statement

No potential conflict of interest was reported by the authors.

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