THE REVISED HASEGAWA’S DEMENTIA SCALE(HDS-R)
— EVALUATION OF ITS USEFULNESS AS A SCREENING TEST FOR DEMENTIA
YUKIMICHI IMAI & KAZUO HASEGAWA
Summary
Revised Hasegawa’s dementia scale (HDS-R), consisting of 9 simple questions with a maximum score of 30, was examined in its usefulness for screening age-associated dementia in a total of 157 subjects: 95 demented patients and 62 non-demented persons. The two groups were age-matched. Cronbach’s coefficient alpha was as high as 0.90 in HDS-R. In addition, the coefficient of correlation of each question’s score to the total score of other questions in the I-IDS-R was significantly high, ranging between 0.79 and 0.40. These findings proved that the HDS-R could satisfy the fundamental prerequisite for dementia screening tests: reliability in terms of internal consistency. Clinical applicability of the HDS-R was confirmed by the following two findings. (a) Significant differences were noted between the demented and non-demented groups in each question’s score, total mean score and mean score by GDS-based severity. (b) Dementia could be most exactly discriminated from non-dementia with sensitivity of 0.90 and specificity of 0.82 at a cutoff point of 20/21 The coefficient of correlation of the HDS-R to the MMSE was as high as 0.94, proving the HDS-R to be valid in terms of compatibility with the established dementia screening test. In conclusion, the HDS-R can screen dementia at the highest conceivable accuracy and efficiency. It may also serve to assess the severity of dementia changing with time and the effect of phannacotherapy and rehabilitation.