Norm values and psychometric properties of the brief symptom inventory-18 regarding individuals between the ages of 60 and 95

Abstract

Abstract Objective The SCL-90 and the SCL-90-R are the most applied measures regarding psychological distress. To reduce and prevent an overload to of the individuals, the Brief Symptom Inventory with 18 items (BSI-18) was developed based on the SCL-90. Since psychological disorders more frequently occur at an older age, there is a growing need for efficient instruments to measure distress in the elderly. However, the BSI-18’s psychometric properties, norm values, and factorial structure have not yet been investigated in this age group. Methods The aim of this study was to evaluate the BSI-18 in a sample of elderly people and to establish norm values for this specific population. Subsequently, demographic information and BSI-18 results were collected from a sample totaling 884 (55% female, mean age of 70.75 years, SD = 7.08, age range = 60–95 years). The questionnaire contains three six-item scales: somatization (SOMA), anxiety (ANX), and depression (DEPR), which form a general symptom index (GSI). Results We found an acceptable to good model fit for a three-factor-model with a general GSI factor. The BSI-18’s psychometric properties were satisfactory. Strict measurement invariance was shown for age and gender. Additionally, we found differences in psychological distress based on sociodemographic variables. Conclusions These findings underline the growing need for preventive mechanisms for elderly people such as, e.g., (re)activating their social networks and strengthening their physical and psychological well-being.

Keywords

• BSI-18
• 60 to 95 years of age
• Psychological distress
• Elderly individuals
• Norm values
• Psychometric properties