comparing the single-item visual analog scale with multi-item hospital anxiety and depression scale, and patient health questionnaire-9 to diagnose depression in patients with idiopathic parkinson’s disease

Background: depression is one of the common non-motor symptoms in patients with parkinson disease (pd), which can have a negative effect on the quality of life of the patients. therefore, it is necessary to have suitable, accurate, cheap, and simple diagnostic tools to identify depression in patients with pd and apply a proper treatment. the current study aimed at comparing the single-item visual analog scale (vas) with the multi-item hospital anxiety and depression scale (hads) and patient health questionnaire-9 (phq- 9) in respect to their sensitivity and specificity to diagnose depression in patients with idiopathic pd. methods: the current cross sectional, comparative study employed the simple non-probability method and selected 79 patients with idiopathic pd, with the mean (sd) age of 59.10 (10.84) years and the average (sd) of disease progression level of 3.24 (1.13), based on hoehn and yahr scale. the single-item scale vas and multi-item tests hads and phq-9 were used as an index tests, and beck depression inventory (bdi) was employed as the reference test to evaluate depression in 3 levels of lack of (or mild) depression, moderate depression, and severe depression using 90% sensitivity and 90% specificity. to determine the sensitivity, specificity, and the ability of each index test in order to diagnose depression, agreement percent of index tests with reference test and receiver operating characteristic (roc) analysis were used. results: the results of roc analysis showed that vas (auc = 0.84) and hads (auc = 0.87) and phq-9 (auc = 0.85) possessed similar abilities to discriminate depression in patients with pd. the sensitivity of vas, hads, and phq-9 tests in moderate or greater thresh- old were 92%, 96%, and 89%, respectively, and in severe threshold were 64%, 79%, and 49%, respectively. specificity of these tests in moderate or greater threshold were 42%, 50%, and 62%, respectively, and in severe threshold were 88%, 77%, and 88%, respectively. the highest agreement level with bdi in mild/moderate and severe levels of depression were found in vas and phq-9, respectively. conclusions: the single-item scale vas, similar to multi-item tests hads and phq-9, had a low to high sensitivity and specificity to diagnose depression in moderate or greater and severe thresholds in patients with pd.