1. IntroductionWith a rapidly aging population, there has been an increase in the number of elderly persons diagnosed with mild cognitive impairment (MCI) [1]. Because of cognitive pathology, older adults with MCI have a lower quality of life (QOL) than those who are cognitively healthy [2,3]. In previous studies, QOL was mostly assessed using a generic instrument. Recently, it has been shown that the Mild Cognitive Impairment Questionnaire (MCQ) is a valid and reliable instrument for evaluating QOL among older people with MCI [4,5,6]. There is a need to adapt the questionnaire transculturally and validate it for use in Chinese.In China, by the end of 2020, the population of older adults aged above 60 years reached 0.26 billion, accounting for 18.7% of the total population [7]. A recent national cross-sectional study [1] indicated that the overall adjusted MCI prevalence was 15.5% (95% CI 15.2–15.9) among older Chinese people aged above 60 years, and the prevalence increased with age. MCI is a clinical pathology that frequently precedes the development of dementia, referring to impairment in cognition that is below normal age-related cognitive decline but not severe enough to cause significantly impaired daily function [8]. MCI is considered to be a transitional stage between normal aging and dementia that causes irreversible decline in physical, cognitive, and social function [9]. The annual conversion rate from MCI to dementia is approximately 15% in community samples and 34% in clinical samples [10], and the probability of developing dementia within five years is as high as 70% [11].MCI is a stage that can determine the onset of clinical cognitive pathology; therefore, early control and management of MCI are very important [12]. Recently, an increasing number of studies have explored the QOL and experiences of people with MCI. A qualitative study indicated that people with MCI experienced cognitive changes (loss of initiative, difficulty in concentrating), impairment in daily activities, uncertainty about their abilities and environmental reactions, and the need to adopt coping strategies with memory aids or repetition [13]. Subjective memory complaint (SMC) is a basic feature of MCI; thus, it is a very common phenomenon in the daily lives of older adults with MCI [14]. Previous studies have indicated that SMC is associated with depressive symptoms and problems in activities of daily living [15,16]. Therefore, the subjective assessment of cognitive impairment and emotional and functional problems is an important aspect of the QOL for patients with MCI. In previous studies, generic instruments, such as SF-36 [3,17], World Health Organization Quality of Life Scale-Brief Form (WHOQOL-BREF) [2,18], EuroQol five dimensions questionnaire (EQ-5D) [19], and World Health Organization Quality of Life Instrument-Older Adults Module (WHOQOL-OLD) [2,18] were used to assess the QOL of patients with MCI. These instruments are all multidimensional and measure QOL domains such as physical, social, and mental functions, and aspects such as vitality, environment (e.g., home environment, healthcare services, financial resources, and transport), pain, self-care, and usual activities [20,21,22]. The SF-36 is one of the most-common health-related QOL instruments, but it has been described as being difficult for the older people to complete [23]. The EQ-5D focuses on whether an individual can perform their usual activities and self-care [21]. Both the WHOQOL-BREF and WHOQOL-OLD originate from the WHOQOL-100 assessment. WHOQOL-BREF includes the four dimensions of physical, psychological, social, and environmental health [22] while the WHOQOL-OLD includes the domains ‘sensory abilities’, ‘autonomy,’ ‘past, present, and future activities’, ‘social participation’, ‘death and dying’, and ‘intimacy’ [20]. However, the above-mentioned instruments are not able to assess cognitive problems.Disease-specific instruments produce more targeted results than generic instruments. A review identified 15 dementia-specific QOL instruments, which included items pertaining to mood, self-esteem, social interaction, and enjoyment of activities [24]. As people with MCI have less functional and cognitive impairment than those with dementia, the issues of QOL in the former are different from the latter. For example, the QOL-AD includes five domains: perceived QoL, behavioral competence, psychological status, interpersonal environment, and physical functioning, and most of them are objective indicators [25]. Therefore, the measures developed to assess the QOL in patients with dementia are not valid for use in MCI. In addition, the instruments to measure QOL of those suffering from dementia are too long, such as health-related QOL for people with dementia with a 28-item self-rated and 31-item proxy-rated version; it was recommended that the two versions be used together [26].For people with MCI, a simple and short self-rated questionnaire was suggested [27]. This 13-item MCQ instrument used to assess the QOL in people with MCI, contains two domains of emotional and practical concerns related to cognitive impairment [5]. It is a simple instrument that can be easily used in various clinical and research settings. Previous studies have shown good reliability and construct validity in the English, Spanish, and Korean versions [4,6,28]. However, it has not been translated or adapted to the Chinese language or context. The purpose of this study was to translate the MCQ into Chinese, to evaluate its reliability and construct validity on the local population and culture of China, and to provide an effective tool to assess the QOL of older adults with MCI. 4. Discussion

In this study, we translated and validated the Chinese version of the MCQ. The results indicated that the Chinese version of the MCQ has good internal consistency and satisfactory construct validity. The non-parametric analysis indicated that the Chinese version of the MCQ had good convergent and discriminant validity in distinguishing between healthy and unhealthy groups.

In the present study, the total score of MCQ was 41.99 (lower score indicating better QOL, SD = 16.13), the practical concern was 44.75 (SD = 16.77), and the emotional concern was 38.76 (SD = 17.14), the scores being higher than those in previous studies [4,5,6]. In the present study, the MoCA cognitive function score was 15.92 (with a lower score indicating higher cognitive function (SD = 6.36) while in the study by Song et al. [6], the MoCA cognitive function score was 17.78, and lower cognitive function was associated with a lower QOL. In addition, in the present study, the score of emotional concern was lower than practical concern (i.e., the emotional level was better than the practical level), and the results were different from those of previous studies. In the original study [5], and the Korean version [6], the score of practical concern was similar to that of emotional concern. In the present study, more than half of the participants were male, whereas in previous studies [4,5,6], almost 70% were female. A possible reason for this was that, compared to older men, older women reported higher levels of emotional problems [40,41]. Additional modifications were required during the translation process. In the present study, we followed the guidelines of translation and linguistic validation process for the Clinical Outcome Assessment, and only one comment about item 5 “slowed down” was received from the review of the original author. In the cognitive debriefing of the pilot test, it was shown that participants with MCI understood the items and responses in the MCQ-Chinese easily.The Chinese version of the MCQ showed good internal consistency of the two dimensions, with Cronbach’s alpha coefficients, and all the total scores were above 0.90. The present study presented results similar to those of the original and Korean studies [5,6] The results of confirmatory factor analysis for the two-factor model with RMSEA of 0.065, CFI of 0.98, and GFI of 0.92 indicated satisfactory construct validity, which was close to the Korean and Spanish versions [4,6]. Correlation analysis revealed a strong negative correlation between WHOQOL-OLD and the three short forms of the WHOQOL-OLD. The findings demonstrated that the MCQ measured a trait similar to the WHOQOL-OLD, suggesting good convergent validity. Since our participants were aged above 75 years, WHOQOL-OLD, specifically designed to address the issues of older adults aged above 60 years, is a reliable and valid instrument to measure QOL [31,32]; WHOQOL-OLD and the short forms are valid measures to assess convergent validity. In addition, the similar correlation between the MCQ-Chinese version and short forms of the WHOQOL-OLD added evidence that the three short forms were equally effective in measuring QOL among older adults [32]. The non-parametric analysis showed that the participants with multimorbidity had significantly higher MCQ scores (indicating lower QOL) than those without multimorbidity, suggesting a good discriminant validity to distinguish between multimorbidity and no multimorbidity. In the present study, the pre-frail and frail participants reported higher scores on the MCQ (lower QOL) than the robust group, which was consistent with previous studies [42,43]. According to Arai et al. [44], cognitive frailty, which is an emerging concept, is defined as a condition of coexisting physical frailty and (MCI); therefore, the MCQ measure could be useful in understanding cognitive frailty. 4.1. Clinical Implication

These results have implications for clinical nursing. The current study obtained promising results regarding the psychometric properties of the MCQ when used among institutionalized older people. The fact that the MCQ-Chinese quickly provides a total score for QOL and the simplicity of its administration will facilitate its use to assess the effect of interventions for older adults with MCI. In addition, the significant difference in MCQ scores between the different frailty groups suggests that the MCQ-Chinese could be used on patients with cognitive frailty.

4.2. Methodological Considerations

This study has some limitations, such as the convenience sampling method that was used, and that data was collected from aged centers in one city in South China, which could influence generalizability. Another limitation was the inclusion criteria “being 75 years or older,” due to which some patients aged younger than 75 years were not included in the study. As it was the staff who assembled the older adults for the survey, there may have been gatekeeper problems in the data collection. For frailty, the missing data was rather substantial while they were only used to test the discriminant validity of the MCQ. The last limitation was that test-retest reliability was not determined for the MCQ-Chinese. This study has some strengths as well. In the present study, the response rate was high, and there were a few missing internal data points that were substituted with the median of the individuals for that factor. The CFA indicated satisfactory construct validity as well as good convergent and discriminant validity. The MCQ-Chinese had a high Cronbach’s alpha values for internal consistency, ranging from 0.92 to 0.96 for the total and subscales, respectively.