Validation of the General Practitioner Assessment of Cognition - Chinese version (GPCOG-C) in China

Abstract

Background: To assess the reliability, validity, and diagnostic utility of the Chinese version of General Practitioner Assessment of Cognition (GPCOG-C). The GPCOG, which is specifically designed for use in primary care to screen for cognitive impairment, consists of a patient section testing cognition, and an informant section asking about decline in cognitive and functional abilities.

Methods: The English version of GPCOG was translated, back-translated, and subsequently revised to determine the final GPCOG-C. Our sample comprised 253 community-dwelling volunteers with memory concerns aged 50 years and over and 103 outpatients of a psychogeriatric clinic with memory complaints. Participants were assessed by one of the four general practitioners or six psychogeriatricians. The Mini-Mental State Examination (MMSE), the Hasegawa's Dementia Scale (HDS), and the GPCOG-C were compared against the DSM-IV-defined dementia diagnosis.

Results: The internal consistency (Cronbach's α) was 0.68 for the GPCOG patient section. The test-retest was 0.98 for the GPCOG-C total. The sequential administration of both components of GPCOG-C had a sensitivity of 97% and a specificity of 89%, with a positive predictive value of 72% and a negative predictive value of 99%. Both the GPCOG-C total and sequential two-stage scoring methods performed at least well as the MMSE and HDS in detecting dementia. The administration time for the two-stage approach was 4.3 ± 2.4 min.

Conclusions: The GPCOG-C is a valid, time efficient instrument for dementia screening in China.