WeChat is one of the most popular SNSs in China and currently boosts of over 600 million active users worldwide (CNNIC, 2015). WeChat is a cross-platform communication application combining popular features of Facebook and WhatsApp (Wu, 2014). It allows users to create a profile, search for friends or find new friends within one's geographical location. On this profile, users can send instant text messages, voice notes and make free voice calls. Further, WeChat allows users to post information, pictures and videos of interest, and comment on friends' posts. All of these features make WeChat popular for online socializing.

Another popular SNS in China is Weibo, created in 2009, and has more than 204 million users (CNNIC, 2015). Weibo allows users to post 140-character information. Similar to Twitter, but unlike WeChat, Weibo focuses on sharing of opinions and information exchange rather than on social interaction (Kwak et al., 2010); and offers some anonymity in online communication (Huberman et al., 2008). Weibo does not need users to post their private information to find “friends” and it focuses less on “who you are” and more on “what you say” (Huberman et al., 2008).

The reduction of social pressure brought about by anonymity (Hughes et al., 2012) may mean different motivation for using Weibo from WeChat. Further, a previous study of interest found that only 2 out of 10 interviewed people had used WeChat to search for new friends (Hou et al., 2017). This entails that most people use WeChat to keep in touch with friends they made in real life. It is hence expected that these differences will be evident in the relationships between individual traits and excessive use of WeChat and Weibo.

A number of personality traits appear to be associated with the use of SNSs. The Big-Five personality test, developed by Goldberg (1999), is the most commonly used model in investigating the relationship between internet use and individual personality (Landers and Lounsbury, 2006; Ehrenberg et al., 2008). The Big-Five personality test consists of five factors: neuroticism, extraversion, openness, agreeableness, and conscientiousness (McCrae and John, 1992). Several of the factors are associated with problematic use of online social media, such as blogs (Guadagno et al., 2008) and SNSs (Ross et al., 2009; Amichai-Hamburger and Vinitzky, 2010; Correa et al., 2010).

Neuroticism is characterized by anxiety, hostility, depression, self-consciousness, impulsivity, and fragility. Individuals who are low in this trait tend to be more stable and emotionally resilient. Butt and Phillips (2008) found that people with high scores in neuroticism use the Internet frequently, spent more time on Facebook (Ryan and Xenos, 2011) and instant messenger (Correa et al., 2010). Neurotics prefer to use the Internet to relieve loneliness and find a sense of group belonging (Amichai-Hamburger and Ben-Artzi, 2003; Butt and Phillips, 2008). In the current study, we hypothesized that those with high scores in neuroticism will excessively use Weibo more than WeChat (H1).

Extraversion is characterized by excitability, sociability, talkativeness, assertiveness, and high amounts of emotional expressiveness. People who are high in extraversion (also called extroverts) are like to be in touch with people, are full of energy and often feel positive emotions. People who are low in extraversion (also called introverts) are quiet, cautious, and don't like excessive contact with the outside world. Extraverts have been found to be excessive users of instant messaging and SNSs (Correa et al., 2010). They have more friends online (Amichai-Hamburger and Vinitzky, 2010) and tend to make even more friends offline (Ross et al., 2009). Thus, extraverts like socializing, but they don't take online socializing as a substitute for real life social interaction. Thus, extraverts use SNSs mainly for social enhancement. People with only a few offline contacts compensate for their introversion, low self-esteem, and low life-satisfaction by using Facebook for online popularity (Ellison et al., 2007; Barker, 2009; Pollet et al., 2011). In this study, we hypothesized that extraversion will positively correlate more with excessive use of WeChat than Weibo (H2).

Openness has the characteristics of imagination, aesthetics, rich emotions, differences, creativity, intelligence, etc. People who score high in this trait prefer abstract thinking and have a wide range of interests. People who score low in this trait are practical, preferring conventions, and more traditional and conservative. Individuals who score high on openness have been found to excessively use instant messaging and SNSs (Correa et al., 2010). They have wide interests and curiosity (McCrae and Costa, 1987), so they prefer to use Internet for information seeking (McElroy et al., 2007). So, since Weibo can provide more new information than WeChat, in this study, we expected that the excessive use of Weibo would be more in open people than WeChat (H3).

Agreeableness has qualities such as trust, altruism, outspokenness, compliance, modesty, empathy, and so on. People who score high in agreeableness are considerate, friendly, generous, and helpful and willing to give up their own interests for others. Agreeableness has been found to be unrelated to Internet and SNSs' use in many studies (Amichai-Hamburger and Vinitzky, 2010; Correa et al., 2010). However, Ross et al. (2009) pointed out that less agreeable people interact more online and take Internet as a tool to improve social skills and build friendships. La et al. (2009) found that females scoring high on this trait posted significantly more pictures than females scoring low, with the opposite being true for males. In the current study, we hypothesized that agreeableness will negatively correlate more with excessive use of Weibo than WeChat (H4).

Conscientiousness shows the characteristics of competence, impartiality, coherence, due diligence, achievement, self-discipline, discretion, and restraint. Those who score high on conscientiousness are responsibility, dedication to work, and seriousness. Numerous studies have found significant negative correlation between conscientiousness and SNSs' use time (Amichai-Hamburger and Vinitzky, 2010; Ryan and Xenos, 2011). Butt and Phillips (2008) suggested that conscientious people do not allow SNSs to disrupt their important work. They may prefer Twitter to Facebook because “tweets” are limited to 140 characters, which mean just a temporal distraction for them (Hughes et al., 2012). In addition to this, people with high conscientiousness were found to have significantly more friends and to upload significantly fewer pictures than those scoring low on this personality trait (La et al., 2009). Thus, conscientious people tend to cultivate their online and offline contacts more without the necessity to share too much personal information publicly. We hence hypothesized that conscientiousness will negatively correlate with the excessive use of WeChat (H5), but will not correlate with the excessive use of Weibo.

Ross et al. (2009) argued that the Big Five might be too broad when assessing individual differences in SNS usage. Taking into account the characteristics of SNSs, this study included different psychological factors, namely loneliness, social support, external locus of control, and social interaction.

Loneliness is considered as one of the most important predictors of internet addiction (Baumeister et al., 2005; Wang, 2006; Bozoglan et al., 2013). Lonely people usually report less support from their social network in real life (Routasalo et al., 2006). McKenna et al. (2002) found that people who feel lonely are more likely to prefer online social interactions than face-to-face settings (Clerkin et al., 2013; Ye and Lin, 2015). Further, people with low real life social support and high virtual social support tend to draw support from online communication (Yeh et al., 2008).

Admittedly, causal direction of this relation is not clear. There is a two-way relationship between loneliness/social support and SNS use. On the one hand, lonely individuals are attracted to SNS to relieve loneliness or get support; on the other hand, excessive use of SNS has been found to increase sense of loneliness (van den Eijnden et al., 2008). Further, through internet communication, particularly communication with known people, lonely people can increase sense of social support (Shaw and Gant, 2002). Based on socializing features of WeChat, which mainly features people one interacts with in real life and the anonymity of Weibo, we hypothesized that lonely people and those with lack of real life social support will excessively use Weibo more than WeChat (H6, H7).

Locus of control refers to the extent to which individuals believe that they can control things that affect them (Rotter, 1966). People with high external locus of control believe that their lives are controlled by luck, fate and chance (Ndasauka et al., 2016) and not by their effort or ability. Such people are more likely to engage in problematic internet use (Chak and Leung, 2004), have more online social interaction (Koo, 2009; Ye and Lin, 2015) and have low social interaction skills (Cloitre et al., 1992; Stipek, 1993). With diminished social interaction skills, they prefer communicating through the internet, where they can contact with others without face-to-face interaction (Ndasauka et al., 2016). In the present study, we expected that external locus of control will positively correlate with excessive use of both WeChat and Weibo (H8). We also hypothesized that social interaction in real life will negatively correlate with excessive use of Weibo more than WeChat (H9).

Total number of participants was 714; 273 males (38.2%), 441 females (61.8%), and were recruited from 3 college campuses in Anhui province, East China. The mean age was 19.8 years (SD = 1.3) ranging from 17 to 21, and 11 participants were under 18 years old.

The study was approved by the Human Research Ethics Committee of the University of Science and Technology of China (USTC). All participants gave consent to participate in the study and principles expressed in the Declaration of Helsinki were closely followed. Participants were undergraduate students.

We did not obtain informed consent from the next of kin, caretakers, or guardians on behalf of the minors/children (under 17 years) enrolled in our study. These young college students were considered to have comparable intelligence and ability to adult students, and able to take charge of their behaviors. According to the General principles of the Civil Law of the People's Republic of China; “A minor aged 10 or over shall be a person with limited capacity for civil conduct and may engage in civil activities appropriate to his age and intellect; in other civil activities, he shall be represented by his agent ad litem or participate with the consent of his agent ad litem” (Article 12, Chapter II). Therefore, we obtained the same consent from these participants between 17 and 18 as those above 18 years old, which was also approved by the Human Research Ethics Committee of the University of Science and Technology of China (USTC). Small gifts (keychain and nail-cutter of not more than $1.5) were given as incentive to participate in the study. Written informed consent was obtained from all participants.

We analyzed the data using the statistics software package SPSS 23.0. We calculated correlations between the scales using Pearson's r (Pearson product-moment correlation coefficient). To test significant differences of different levels in total scores, we used the Kruskal–Wallis test (Kruskal–Wallis one-way analysis of variance) and t-tests. We also used Scheffe's post-hoc tests to analyze significant differences between different levels. Further, we used a method by Lee and Preacher (2013) to calculate the difference in correlations between WEUS ↔ personality traits and MEUS ↔ personality traits. The significance level in this study was p ≤ 0.05.

With regard to preference, 386 participants (females = 261) reported that they preferred Weibo to WeChat, while 328 participants (females = 180) reported that they preferred WeChat to Weibo. We used the chi-square test to calculate the gender proportion, and there was significant difference between the usage proportion of Weibo and WeChat (χ² = 12.184, p < 0.001), with more females preferring Weibo to WeChat.

We analyzed the correlation between MEUS and WEUS. Results showed significant positive correlation between the two variables (r = 0.462, p < 0.001).

We analyzed the correlation between MEUS and the four personality traits (see Table 1). MEUS positively correlated with Neuroticism (r = 0.173, p < 0.001), negatively with Agreeableness (r = −0.234, p < 0.001), and Conscientiousness (r = −0.083, p = 0.026), but did not significantly correlate with Extraversion (r = 0.007, p = 0.852).

We then analyzed the correlation between WEUS and the four personality traits (see Table 1). WEUS positively correlated with Neuroticism (r = 0.118, p < 0.001), negatively with Agreeableness (r = −0.153, p < 0.001) but did not significantly correlate with Conscientiousness (r = −0.025, p = 0.503) and Extraversion (r = 0.057, p = 0.128). For the significant correlations, we also draw the scatter plot on the relationship between MEUS/WEUS and the four personality traits (see Figure 1).

Further, we found significant difference between correlations of MEUS ↔ Agreeableness and WEUS ↔ Agreeableness (z = −2.14, p = 0.033). These results were consistent with H4 and H1, H2, H3, H5 were not supported.

Our results showed that loneliness positively correlated with MEUS (r = 0.139, p < 0.001) but did not significantly correlate with WEUS (r = 0.025, p = 0.508; see Table 1). We analyzed the difference between these two correlations and found that correlation between loneliness and MEUS was significantly higher than correlation between loneliness and WEUS (z = 2.931, p = 0.003).

Further, we found that social support negatively correlated with MEUS (r = −0.111, p = 0.003), but did not significantly correlate with WEUS (r = −0.048, p = 0.200; see Table 1). For the significant correlations, we also draw the scatter plot on the relationship between MEUS/WEUS and loneliness/social support (see Figure 1).

We then analyzed the difference between the two correlations and found that the two correlations were not significantly different (z = 1.627, p = 0.104). These results were consistent with H6 and H7 is not supported.

We analyzed the correlation between MEUS and external locus of control/real life social interaction (see Table 1). MEUS correlated positively with external locus of control (r = 0.178, p < 0.001), and negatively with real life social interaction (r = −0.084, p = 0.024).

We then analyzed the correlation between WEUS and the two variables (external locus of control and real life social interaction; see Table 1). WEUS correlated positively with external locus of control (r = 0.208, p < 0.001), but did not significantly correlate with real life social interaction (r = −0.008, p = 0.822). For the significant correlations, we also draw the scatter plot on the relationship between MEUS/WEUS and external locus of control/social interaction in real life (see Figure 1).

While the correlation of MEUS and external locus of control did not significantly differ with correlation of WEUS and external locus of control (z = 0.79, p = 0.429), correlation of MEUS and real life social interaction was significantly higher than correlation of WEUS and real life social interaction (z = 2.243, p = 0.025). These results were consistent with H9 and H8 is not supported.

Applying the Bonferroni correction, we divided p = 0.05 by the number of tests (10) to get the Bonferroni critical value. This resulted in change of p-value to p < 0.005 to be significant. Under that criterion, all tests were found to be significant except for correlation between MEUS and Conscientiousness whose p = 0.026 and MEUS and real life social interaction whose p = 0.024.

From the item- “which one do you prefer, Weibo or WeChat?” results showed that more females preferred Weibo to WeChat than males. This is consistent with previous studies that females scored significantly higher on the Weibo scale than males (Hou et al., 2014), and women are more likely to use Twitter than men (Smith and Rainie, 2010). By broadcasting to everyone, Weibo allows young female students to express themselves to and seek attention from a larger audience than they would on WeChat, which is limited in its broadcasting and sharing of moments.

Also, we found that Weibo and WeChat had significant moderate correlation with each other. These results may mean that users of one also tend to use another. However, the results may also entail that there is some difference between Weibo and WeChat.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.