Measuring symptoms and diagnosing mental disorders in the elderly community: The test-retest reliability of the CIDI65+

Prevalence findings for the elderly are artificially low, most likely due to insufficient consideration of age-related cognitive abilities in diagnostic interviews. Aims: (1) To describe the rationale for the development of an age-adapted Composite International Diagnostic Interview (CIDI65+) for use in a European project (MentDis_ICF65+). (2) To examine its test-retest reliability. Methods: Based on substantive pilot work the CIDI standard questions were shortened, broken down into shorter subsets and combined with sensitization questions and dimensional measures. Test-retest was determined in N=68 subjects aged 60-79 years via two independent examinations by clinical interviewers using kappa (sensitivity, specificity) for categorical and intraclass correlation (ICC) coefficients for dimensional measures. Results: Test-retest reliability was good for any mental disorder (κ=0.63), major depression (κ=0.55), anxiety (κ=0.62, range=0.30-0.78), substance (κ=0.77, range=0.71-0.82), obsessive-compulsive disorder (κ=1.00) and most core symptoms/syndromes (κ range=0.48-1.00). Agreement for some disorders (i.e. somatoform/pain) attenuated, partly due to time lapse effects. ICC for age of onset, recency, quantity, frequency and duration questions ranged between κ=0.60-0.90. Dimensional agreement measures were not consistently higher. Conclusion: The age-adapted CIDI65+ is reliable for assessing most mental disorders, distress, impairment and time-related information in the elderly, prompting the need to examine validity.