A psychometric evaluation of the French Canadian version of the Hospital Anxiety and Depression Scale in a large primary care population

Background: The aims of this study were to: (1) evaluate the psychometric properties of a French Canadian version of the Hospital Anxiety and Depression Scale (HADS-FC) in a large population of primary care patients in Quebec, Canada; (2) conduct a transcultural validation of the original HADS in a subsample of English-speaking patients; (3) explore HADS properties in subgroups with or without multimorbidity. Methods: A sample of 14,833 adults recruited in 64 primary care clinics completed the HADS, including 3,382 patients at elevated risk of mental disorders that also completed the Composite International Diagnostic Interview-Simplified (CIDIS). The HADS' internal consistency and discriminant validity were assessed, its factor structure was evaluated, and receiver operating characteristic (ROC) analyses were undertaken to evaluate its case finding abilities. Results: The HADS-FC had good reliability (Cronbach's alphas ranging from 0.79 to 0.89 depending on language version and subscales) and discriminant validity, and a two-factor structure reflecting anxiety and depression factors. Results were similar in patient subgroups with or without multimorbidity. Optimal cut-off values were calculated: HADS: >= 16 (sensitivity 62%, specificity 77%), HADS-A: >= 10 (sensitivity 66%, specificity 73%) and HADS-D: >= 7 (sensitivity 65%, specificity 75%). Limitations: Our cohort selection process and use of the CIDIS as a gold standard may have contributed to the limited case-finding performance of the HADS-FC. Conclusions: The HADS-FC and English HADS presented good psychometric properties in primary care patients, including patients with and without multimorbidity. However, its performance as a screening instrument in these settings with patients of varying clinical profiles requires more scrutiny. (C) 2012 Elsevier B.V. All rights reserved.