Reliability and validity of the Center for Epidemiological Studies Depression Scale in 2 special adult samples from rural China

Abstract

Few studies on the validation of the Center for Epidemiological Studies Depression Scale (CES-D) in Chinese have been conducted in the samples from rural area, whereas the mental health problems among rural Chinese deserve more attention. For instance, the suicide rate in rural China is about 3 times that of the urban rate. This study aimed at assessing reliability and validity of the CES-D in 2 special adult samples in rural China, with data obtained by face-to-face interviews. One sample consisted of the proxy informants for subjects who committed suicide, and the other was of the proxy informants for living controls. For each person who committed suicide and each control, a family member and close friend served as informants. This study focused on informants themselves (not the persons who committed suicide or the living control himself/herself). Suicide informants (n = 781) who had experienced the suicide of a relative or close friend in the past 6 months were compared with the control informants (n = 832) who had no such experience. Internal reliability was satisfactory (Cronbach coefficients were .949 for suicide informants and .880 for control informants). Good concurrent validity and criterion validity were found by analyzing the relations to negative life events and the Scale for Suicide Ideation. Confirmatory factor analyses indicated that 3-factor structure (positive affect, interpersonal problems, depressive mood and somatic symptoms combined) had good fit in rural Chinese. These findings suggested that the CES-D had good reliability and validity when applied in these 2 adult samples in rural China. Factor structure analyses of the CES-D indicated that “somatization” process of expressing depressive symptoms still existed among rural Chinese.

Introduction

In China, suicide was responsible for about 287 000 deaths each year and was the fifth most important cause of death not long ago [1]. In the past decade, suicide rate in China has declined probably because of the tremendous economic growth in China [2], [3], and the trend different from the West arouses great interest in the Chinese mental health issue. Furthermore, of the 1.37 billion population in China, about 70% live in rural areas [4], and about 93% of suicides in the nation happened in the rural areas [5], [6], [7]. The rural rate of suicide is about 3 times that of the Chinese urban rate [8], [9]. All these facts warrant our attention toward Chinese rural mental health.

Depression, as a major diagnosis among all types of mental disorders that occur before suicide [10], [11], [12], is an important variable for research. Depression has been conceptualized and operationalized in 2 ways in previous research: (1) as a depressed mood (as evidenced by a large number of depressive symptoms) and (2) as a psychiatric disorder that meets conventional diagnostic criteria (eg, major depressive disorder) [13]. In most studies that use the method of the general population or community survey, the Center for Epidemiological Studies Depression Scale (CES-D) [14] is the most commonly used to measure depressive symptoms [13].

The CES-D is a self-report scale, and it covers affective, cognitive, behavioral, and somatic symptoms associated with depression. The CES-D was originally developed for assessing depression symptoms and was specifically designed for research use in the general and nonclinical populations [14]. Numerous studies have documented the good reliability and validity of the CES-D in both community and clinical samples. The scale has been used in research on children and adolescents [15], [16], [17], adult and older populations [18], [19], [20], and the physically ill [21] and the mentally ill populations [22].

The CES-D Chinese versions have been used among various Chinese populations for hypothesis testing, such as overseas Chinese in the United States [23], [24], [25], Chinese in Hong Kong [26], and Chinese in mainland China [27], [28], [29], [30], [31], [32], [33]. In some other studies, the reliability and validity [23], [25], [29], [34], [35] of the CES-D have been tested among Chinese populations. They have demonstrated that this scale could be applied in these Chinese.

However, few studies on the CES-D have been conducted using Chinese rural samples. People in rural areas account for about 54.3% of the Chinese total populations [36], and there is a great demand to study the rural mental health in China. It has been reported that the rate of suicide in Chinese rural people was 3 times that of Chinese urban people [8], [28]. Therefore, introducing a widely spread method to screen and test the mental health in rural Chinese will be significant and beneficial not only for exploring the mental disorder status but also for the cross-culture comparison. Using a large-scale rural population, the current study aimed to assess the psychometric properties of the CES-D applied in 2 rural Chinese samples with different demographic characteristics.

In the report of Radloff [14], a principal component factor analysis with Varimax rotation was used and obtained the 4 interpretable factors: (1) depressed affect—feeling blue, depressed, lonely, crying, and sad; (2) positive affect—feeling good, hopeful, and happy and enjoying things; (3) somatic and retarded activity—bothered, loss of appetite, needing effort, poor sleep, and trouble getting going; and (4) interpersonal—unfriendly and feel disliked. Following Radloff's original factor structure, a number of studies explored the factor structure of the CES-D by exploratory factor analysis (EFA) or by confirmatory factor analysis (CFA) or by both methods.

Investigators also examined the factor structure in Chinese, but the results varied in different groups. Ying [23] found that the factor structure by EFA and CFA derived from Chinese Americans revealed 3 primary factors: positive affect, interpersonal problems, and depressive mood and somatic symptoms combined. With EFA, the 3-factor structure attained from the data of urban people in mainland Chinese is as follows: somatic/retarded activity, interpersonal problems, and depressed affect [29]. A Chinese American student sample yielded a 5-factor solution [23]. A study in Chinese high school students suggested that the 4-factor model showed the best fit than the 3-factor model, 2-factor model, and 1-factor model [37]. Using CFA in the Chinese data from Hong Kong, Cheung and Bagley [26] reported 2 factors: affective and somatic symptoms and interpersonal problems. Another research from Hong Kong community adolescents demonstrated, using CFA, adequate fit both with Radloff's 4-factor structure and the 3-factor structure of Yen et al [35] including positive, somatic (mixing items from Radloff's somatic and depressed affect factors), and affective [34].

In a review of the above studies, most of the findings included the factor of “interpersonal problems,” whereas “somatic symptoms” and “depressive mood” were likely combined into 1 factor. Actually, the latter indicated that, for the factor structure of the CES-D in Chinese, the pivot of debates was somatization vs “psychologization” of distress in Chinese (eg, Cheung and Bagley [26]). The debate implied a cross-culture issue when a Western scale was introduced into non-Western culture. Some researchers noted that Chinese patients have fewer complaints of emotional conflicts and tend to express their emotional disturbance through somatic symptoms [38], [39]. As early as last century, Kleinman and Kleinman [40] found that Chinese tend to minimize the difference between depressive and somatic symptoms: they somatize depressive symptoms by voicing bodily complaints and seeking medical help. Under this cultural background, the factors “depressed affect” and “somatic and retarded activity” in Radoff's original structure model might be merged into 1 factor. Other studies suggested that compared with the factor structures found in American community samples, there is a closer link between depressive affect and somatic symptoms for the Chinese populations [23], [26], [34], [35].

In another study using the general population in a urban area of China, Lin [29] reported that Chinese in urban areas could present complaints of depressed mood according to the result of factor structure analysis (3-factor structure was found and included both somatic symptoms and depressed affect) [29]. In the present study, we hypothesized that Chinese in rural area were more likely to report somatize depressive mood compared with urban Chinese because rural Chinese were relatively more traditional and less educated with lower social economic status in China. It is noted that the annual per capita net income in rural population is 5919 RMB, whereas that in urban population, it is 19 109 RMB [41]. They are also less exposed to psychiatric education than their urban counterparts [42]. All those rural factors have contributed to the somatization of mental symptoms among the rural people in China. As Kleinman reminded, after he analyzed the causes of the experience of depression being physical rather than psychological in Chinese society, Chinese clinicians should pay special attention that “poverty and joblessness frequently intensify cultural issues” [43].

This current study tries to contribute to the current literature on the CES-D with Chinese rural and nonclinical samples. It is also our aim to make a preliminary attempt to find out special cultural relevance and interpretation when the scale was used in Chinese context.