Development of a Revised Version of Subjective Memory Complaints Questionnaire in Taiwan: A Preliminary Study.

Abstract

Research has suggested that subjective memory complaints (SMC) are predictive of cognitive decline in cases of Alzheimer's disease; however, multidimensional characteristics of SMC make it difficult to formulate causal links. The Subjective Memory Complaints Questionnaire (SMCQ) has proven effective in capturing the nature of SMC. In this study, we developed a revised version of SMCQ (SMCQ-R) with corresponding normative data for application in Taiwan. This study recruited 100 cognitively normal participants (> 45years) stratified according to demographic characteristics. Assessments were performed to evaluate test-retest reliability, criterion-related validity, and construct validity of SMCQ-R. SMCQ-R scores of 20 matched patients with mild cognitive impairment (MCI) were also compared with those of normal participants to test construct validity. Reliability of SMCQ-R was satisfactory (0.81-0.95). Factor analysis revealed a three-factor structure: everyday memory problems (EMP), recent severe memory problems (RSMP), and long-term memory problems (LTMP). EMP and RSMP scores were negatively associated with objective cognitive function (r = -.20 to .39). Depressive symptoms were positively associated with all factors (r = .23-.33). Age was positively associated with total (b = 0.09, p < .05) and EMP scores (b = 0.06, p < .01). MCI patients obtained higher scores (p < .05) on all subscales. SMCQ-R scores discriminated between normal and MCI individuals (area under the curve = 0.77). This study established a norm based on scores adjusted to control for effects of age. SMCQ-R has sound psychometric properties and could potentially be used as a tool to assess SMC in clinical settings.