Reliability and concurrent validity of Alzheimer’s disease assessment scale - Cognitive subscale, Chinese version (ADAS-Cog-C) among Chinese community-dwelling older people population

Abstract

Objective

To evaluate reliability and concurrent validity of the Alzheimer’s Disease Assessment Scale - Cognitive Subscale, Chinese Version (ADAS-Cog-C) among Chinese community older adults.

Method

Three groups, comprising of 1,276 community-dwelling older adults, were included in this study: a normal control (NC), a mild cognitive impairment (MCI), and an Alzheimer’s disease (AD) group. All participants were assessed through ADAS-Cog-C, clinical interviews, physical examinations, Mini Mental State Examination (MMSE), and the Clinical Dementia Rating Scale (CDR). Internal consistency was assessed to evaluate the reliability of ADAS-Cog-C. Pearson and Spearman correlation coefficients were calculated to evaluate the concurrent validity between ADAS-Cog-C, MMSE, and CDR.

Results

Overall, the Cronbach’s alpha coefficients of ADAS-Cog-C for the AD and MCI groups were 0.843 and 0.554, respectively. The split-half reliability coefficients for the AD and MCI groups were 0.860 and 0.539, respectively. ADAS-Cog-C scores were negatively correlated with MMSE scores (r = −0.706, p < 0.001) and positively associated with CDR scores (r = 0.546, p < 0.001). After excluding the MCI group from the analysis, the internal consistency of ADAS-Cog-C for the total population improved (α = 0.813, r_hh = 0.852, all p < 0.001), as did the correlation between ADAS-Cog-C and MMSE (r = −0.828, p < 0.001) and CDR (r = 0.429, all p < 0.001) scores.

Conclusions

ADAS-Cog-C has good internal consistency and concurrent validity for assessing Chinese community older adults with AD, but poor consistency, good concurrent validity with the MMSE while moderate concurrent validity with the CDR for MCI.

Keywords:

• ADAS-Cog
• Alzheimer’s disease
• concurrent validity
• mild cognitive impairment
• reliability

Disclosure statement

The authors declare that they have no conflicts of interest.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, ZC. The data are not publicly available due to their containing information that could compromise the privacy of research participants.

Additional information

Funding

This work was supported by The Social Development Key Projects in Jiangsu Province (Grant BE2015615).

Notes on contributors

Yan Jiang

Yan Jiang, graduate student of Nanjing Medical University, The Affiliated Wuxi Mental Health Center of Nanjing Medical University, No.156 Qianrong Road, Wuxi, Jiangsu Province, China.

Hongyu Yang

Hongyu Yang, graduate student of Nanjing Medical University, The Affiliated Wuxi Mental Health Center of Nanjing Medical University, No.156 Qianrong Road, Wuxi, Jiangsu Province, China.

Jinfa Zhao

Jinfa Zhao, graduate student of Wannan Medical College, No.22 Wenchang Road, Wuhu, Anhui Province, China.

Yue Wu

Yue Wu, Associate Chief Physician of Nanjing Medical University, The Affiliated Wuxi Mental Health Center of Nanjing Medical University, No.156 Qianrong Road, Wuxi, Jiangsu Province, China.

Xiaoqin Zhou

Xiaoqin Zhou, Department of Science and Education of Nanjing Medical University, The Affiliated Wuxi Mental Health Center of Nanjing Medical University, No.156 Qianrong Road, Wuxi, Jiangsu Province, China

Zaohuo Cheng

Zaohuo Cheng, MD, Professor of Nanjing Medical University, The Affiliated Wuxi Mental Health Center of Nanjing Medical University, No.156 Qianrong Road, Wuxi, Jiangsu Province, China.