Screening for dementia using telephone interviews

To assess cognitive impairment or dementia in epidemiologic studies using telephone interviews for data acquisition, valid, reliable and short instruments suitable for telephone administration are required. For the Telephone Interview for Cognitive Status (TICS) in its modified German version, the only instrument used in Germany so far, more data on reliability and practicability are needed. Participants were recruited in the offices of nine primary care physicians. Data from 197 participants (115 females, mean age 78.5 +/- 4.1 years) who were tested by telephone and in the office by means of the Mini-Mental State Examination (MMSE) were used for the evaluation. For assessing reliability, a group of 91 participants (55 females, mean age 78.1 +/- 4.1 years) was contacted twice during 30 days to be tested during a telephone interview by means of the TICS in its modified German version. The intraclass correlation coefficient (ICC), a measure of reliability, was 0.67 [95% confidence interval (CI): 0.53; 0.77]. The Bland-Altman plot did not reveal any relationship between the variability of the difference between repeated measures and the total amount of the measure. For the overall TICS score, no differences were found between repeated measurements. However, the tasks recall of the word list and counting backwards showed some improvement in the repeated tests. TICS and MMSE showed only moderate correlation, with a correlation coefficient of 0.48 (95% CI: 0.36; 0.58). TICS values were dependent on age and educational level of the person tested. The TICS in its modified German version appears to be of acceptable reliability for the assessment of cognitive impairment during a telephone interview. TICS values depend on age and educational level of the person tested. TICS and MMSE correlate only moderately.