Comparison of the Beck Anxiety Inventory and the Geriatric Anxiety Scale in an Older Adult Neurology Clinic Sample.

Abstract

Objective: The Beck Anxiety Inventory (BAI) is a commonly used anxiety measure, but it was not specifically designed for use among older adults. Previous research has raised concern that it may inflate anxiety ratings among older adults because of its emphasis on physical symptoms. The Geriatric Anxiety Scale (GAS) is designed for older adults but has not been examined in a neurology clinic setting. This study sought to compare the psychometric properties of the BAI and the GAS in an older adult neurology clinic sample. An exploratory aim was to determine the influence of motor symptoms on anxiety scores.

Method: Participants included 68 adults age 60+ referred for a neuropsychological evaluation in an outpatient neurology clinic. Measures included the BAI, GAS, and the Montreal Cognitive Assessment (MoCA). Psychometric properties were determined. A McNemar test compared the proportion of anxiety classifications between the BAI and GAS. Referral source (cognitive disorder versus movement-oriented teams) was used as a proxy for grouping patients who were likely to have prominent motor symptoms versus those who were not. An independent t-test compared scale performance between these groups to examine the influence of motor symptoms on anxiety ratings.

Results: Both scales had good internal consistency (GAS α = 0.93; BAI α = 0.88). Convergent validity (GAS and BAI: r = 0.81, p < .001) and discriminant validity (GAS and MoCA, r = 0.18, p = .20) were supported. The BAI detected anxiety among 40% of participants, while the GAS detected anxiety among 56%, which was a statistically significant difference (p = .002). Anxiety ratings did not differ based on referral source (t(66) = -1.59, p = .12).

Conclusion: Both scales had good psychometric properties, though the GAS detected a higher rate of anxiety compared to the BAI despite having less focus on motor symptoms that could be attributed to age-related physical changes or movement disorders. The GAS may capture aspects of anxiety not assessed by the BAI among older adults.