After obtaining the ethical approval letter from the University Ethics Committee (The Reference number of the ethical approval letter is FHMREC15063), participants were recruited in the northwest of UK for the qualitative study through various ways including social media, emails and word-of-mouth in two universities. The quantitative study targeted Chinese international students in universities across the UK. Information about the survey was distributed via email, Wechat and Facebook with QR code (Note3), which link to the questionnaire electronically.
Chinese international students were invited to participate in the university-approved project through advertisements placed on the home page of the Chinese Students and Scholars Association (CSSA) website and the researcher’s contacts in the social media. The advertisement included a letter explaining the nature of research, the length of the interview/ questionnaire, a statement about confidentiality, an invitation to students interested in being interviewed and surveyed, and the contact address of the researcher, either through e-mail, or click on the link of electronic version of the questionnaire to leave messages.
92 4.3.1 Participants for individual interviews
The recruitment of the sample was criteria based and purposively selected, which offered the researcher a degree of control over the sample composition. With this method, the researcher deliberately sought to ensure that the participants were: from two different universities; in different schools and courses, balanced between genders. The method of criteria-based selection was used to recruit participants (n = 20). Inclusion criteria were: 1) Chinese international students learning at a UK university for an academic degree, coming from mainland China, Hong Kong or Taiwan; 2) 18 years of age or above; 3) agreement to participate in the study; 4) ability to give informed consent; and 5) able to speak Mandarin Chinese or English. Regarding the number of participants, the most widely accepted principle is saturation (Morse, 2015). A recent study (Hennink, Kaiser, & Marconi, 2016) on code saturation and meaning saturation suggests that code saturation was reached at nine interviews, and meaning saturation is gained between 16 to 24 interviews. The reasoning behind the sample size selection was also on heterogeneity, the greater the heterogeneity, the larger the sample that must be selected. Given that the students sample all meet the above criteria, 20 in-depth interpersonal interviews were considered as an appropriate number to conduct in the current study.
Ten female students and ten male students took part in the personal interviews, with ages ranging from 19 to 30, and their length of residence in the UK ranging from six months to seven years. Most of the participants were single at the time of being interviewed except for two. One doctoral student lived with his wife in the UK. His wife was pregnant and went back to China at the time he was interviewed. Another
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one was a female student. She had a husband with a different ethnic background in the UK.
The 20 interviewees were from a wide range of divergent courses and programmes: electric electronic engineering, business management, chemistry engineering, medicine, law, computer science, mechanical engineering, linguistic studies, materials science/engineering and environmental studies as well as cosmos physics. Regarding their academic status, there were six BA students, seven master students and seven doctoral students, so as to ensure that different disciplinary voices were heard.
4.3.2 Participants for questionnaire survey Sample size
The general rule for choosing the size of the sample is to use the largest sample necessary (Gorard, 2010). Concerning the size of the sample, heterogeneity of the participants was a key factor. In terms of the heterogeneity of the population in the current study, the main criterion was that participants were all Chinese international students studying in the UK. The pilot study showed that the participants were homogeneous in demographic characteristics.
A sample size of 30 should be the minimum for statistical analysis (Cohen, Manion, & Morrison, 2013). Kline (1998) recommended that in a path analysis 5-10 participants are needed for each parameter to be estimated. In the present study, a total of 6 free parameters were to be estimated, resulting in a sample size of 60 to complete the survey. To better understand the health and well-being experiences of Chinese international students, 302 participants were recruited throughout the UK. Regarding
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sample size, the confidence interval approach was adopted to determine the sample size in the survey. The minimal sample size of the current study was calculated according to the following formula (Chow, Wang, & Shao, 2007).
n = z2 (pq)/ e2 where: n = sample size
z = standard error associated with the chosen level of confidence p = estimated variability in the population
q = 100 – p
e = acceptable error
The confidence interval was identified as 95%, with a corresponding z score of 1.96. The acceptable error was assumed to be +/-5%, which implies 95% accuracy in estimating the total population by this sample. Accordingly, the theoretical sample size of the study was calculated to be 113, which was used to guide the amount of the data collected in the current study. The final sample consisted of 302 participants and exceeded the number as advised above. As such, the sample size for this study was sufficient.
A total of 302 electronic responses were received for data analysis. Details of the demographic characteristics of the participants are presented in Table 4.1. 42.4% of the students reported as male and 57.6% of the participants as female. The average age of the participants was 24.7 (SD = 3.13).
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Table 4.1 Basic demographic information of participants for quantitative data collection
Characteristics n %
Gender 302
Male 128 42.4
Female 174 57.6
Length of residence in the UK (year) ≦1 84 27.8 1－2 98 32.5 2－3 38 12.6 ＞3 82 27.1 Age (year) ≦23 105 34.8 24－30 185 61.3 31－35 11 3.64 36－40 1 0.33 ≧41 0 0
Health Status (self-assessed)
Very healthy 91 30.1
Healthy 152 50.3
Average health 53 17.5
Unhealthy 6 2.1
Very unhealthy 0 0
English oral communication
< = 4 29 9.6
5－7 273 90.4
English academic writing
< = 4 136 45
5－7 166 55