CIBIC Plus-J Assessment Using a Videotaped Method in Alzheimer's Disease Patients

Background/Aims: CIBIC plus-J is the Japanese language version equivalent to CIBIC plus. Variability of CIBIC plus-J arises among raters in accordance with their experience and their memories of patients’ conditions at baseline. Therefore, in a multicenter trial of Alzheimer’s disease, CIBIC plus-J interviews with Alzheimer’s disease patients were videotaped, and the tapes were assessed by central raters as a means to improve the reliability of CIBIC plus-J assessment. Methods: Two of eight central raters were randomly selected and independently assessed the CIBIC plus-J of each patient. Results: CIBIC plus-J of 41 patients was assessed. The agreement rate between the two raters was 46.3% (19/41), when two raters assessed the CIBIC plus-J of the same patient. However, when considering disagreement between adjacent points as ‘agree’, the agreement rate was 97.6% (40/41). Although the kappa coefficients contained coincidence, simple and quadratic weighted kappa coefficients [95% confidential interval (CI)] were 0.226 (0.066–0.386) and 0.633 (0.507–0.759), respectively, and when considering disagreement between adjacent points as ‘agree’, the agreement kappa was 0.896 (0.752–1.041). The interclass coefficient from the two-way layout model was 0.639. Conclusion: The reliability of the CIBIC plus-J assessment with the videotaped method was acceptable.