The orthostatic hypotension questionnaire in Swedish tested in patients with parkinsonism

BACKGROUND: Orthostatic hypotension (OH) is common among older people and in particular in conditions like Parkinson's disease (PD). The OH Questionnaire (OHQ) has been proposed as a useful patient-reported assessment tool consisting of the OH Symptom Assessment (OHSA), OH Daily Activity Scale (OHDAS), and a composite score.

AIMS OF THE STUDY: To translate the OHQ into Swedish and assess its psychometric properties.

METHODS: Following forward-backward translation, the Swedish OHQ was field-tested (n = 6) for relevance, comprehensibility, and respondent burden. It was then tested regarding scaling assumptions, targeting, reliability, and construct validity in persons with PD (n = 27) and multiple system atrophy (n = 2).

RESULTS: The Swedish OHQ was considered relevant and easy to use, with a mean completion time of 5.3 min. Scaling assumptions were acceptable for OHSA and OHDAS (corrected item-total correlations, .30-.67) but not for the total score (.12-.69). Floor/ceiling effects were ≤3.4% and reliability was >.64. Construct validity was supported by expected correlations with the SCOPA-AUT, RAND-36, and blood pressure measurements.

CONCLUSIONS: The Swedish OHQ was well received, and psychometric results suggest that the OHQ (particularly the OHDAS) is a useful tool for OH assessment in parkinsonian disorders. Further testing in larger samples is needed.