1. Study design
The positive psychology intervention was set as a classroom-based selective course, which was embedded in the regular school curriculum and opened to the medical students at School of Medicine, South China University of Technology (SCUT), Guangzhou, China. The course was open to year-2 and year -3 students only. The attendees who voluntarily consented to participate in the research were asked to complete the questionnaires. They were asked to fill in the questionnaire before and one week after the training course, respectively. All questionnaires were anonymous with the exception of the academic year, gender and age, to avoid participants’ stigmatizing and obtain honest answer as much as possible. No compensation was provided for the participation. To test the effects of the intervention, an identical set of interventions and survey was performed on an independent cohort of students who attended the course voluntarily in the year following the above preliminary study. None of the participants reported any previous experience of positive psychology intervention.
2. Participants
A total of 61 undergraduate medical students at their year-2 or year-3 academic study attended the training course voluntarily in the preliminary study. Only the participants who completed the whole course study, assignments, as well as pre- and post-course questionnaires were included in the analysis. According to this inclusion criteria, of the initial 61 participants recruited to the study, 12 dropped out of the program, giving an attrition rate of 19.7% (12/61). For these 12 students who discontinued the study, their common reasons were that they were too busy to finish the assignments or return the post-course questionnaire. For the 49 participants, their ages range from 17 to 22 years old (mean=19.5, SD=0.94). For the validation cohort, there were 52 students taking part in the course initially, and 46 of them who fulfilled the above inclusion criteria were included in the current analysis. 6 ones of them dropped out of the program due to time limitations. The detailed social demographic characteristics of both participant cohorts are described in Table 1.
3. Procedures
The students who participated in the course were first invited to complete a packet of questionnaires (as detailed in the following Measures section and Appendix 1-5) prior to the commencing of the training course. They then would receive the training and finish the related assignments as tutored for 8 continuous weeks (as detailed in the following Interventions section). Finally, in the week following the completion of the course, they would be given an identical packet of questionnaires to complete. The pre- and post-course questionnaires will then be compared and analyzed. At the same time, an independent survey question would be given at the post-course questionnaire by asking them:“Overall, how do you think of this project?”. Participants were asked to rate their response with a four item Likert-type scale from “No useful at all”, “A little useful”, “Useful” to “Very useful”.
4. Interventions
The intervention was set as 1.5-hour class once a week, and lasted for 8 continuous weeks. The protocol of the intervention, which was detailed in Appendix 6, is derived from Dr. Martin Seligman’s theory of PERMA (Positive emotion, Engagement, Relationship, Meaning, Accomplishment) [37] with slight modification. Briefly, in each weekly class, a different topic related to the cultivation of PERMA will be talked, for example, the cultivation of positive emotional states (e.g. gratitude and appreciation), cultivation of intrinsic motivation through ‘flow”, and learning of being in harmony with the bad mood by highlighting the meaning of life. Additionally, multiple topics related to medical professional (e.g. doctor-patient relationships) were also introduced and discussed in class to guide the students to find the thinking traps using positive psychology theory. At the same time, multiple out-of-class exercises were also assigned, for example, writing down good things and identifying key character strengths. One single teacher led and completed the whole intervention, and the teacher has been trained to be qualified at Center for Positive Psychology and Engineering Psychology, School of Social Sciences at Tsinghua University, Beijing, China, before the class.
5. Measures
The following five scales were used to measure the psychology status of the participants before and after the training, respectively, including trait hope scale, life satisfaction scale, subjective happiness scale, as well as depression and anxiety scale (Appendix 1-5). All these questionnaires were first translated from English into Chinese by one of the authors who were fluent in both Chinese and English. Translations were then checked by another author of the study to ensure the consistency with the original meaning of the scale items. No other adaptations to these scales were made.
5.1 The trait hope scale. The hope trait was measured by using the 12-item Trait Hope Scale[38, 39] (Appendix 1). This questionnaire scale asks respondents to rate their agreement with 12 statements related with hope, which is rated on an 8-point Likert-type scale ranging from 1 (definitely false) to 8 (definitely true) (Cronbach’s α=0.85). A sample item of the scale is: ‘‘I can think of many ways to get the things that are important to me’’. Amongst, 4 items (item 2, 9, 10 and 12 in the questionnaire) measures the goal-directed energy (which is also called agency thoughts), and 4 items (item 1, 4, 6 and 8 in the questionnaire) measures the plans to meet goals (which is also called pathway thoughts). The total trait hope scale score is derived by summing the four agency and the four pathway items, the possible range of which is 8-64 with high scores reflecting high levels of hope.
5.2 Life satisfaction scale. The life satisfaction was measured by using the 5-item satisfaction scale [40, 41] (Appendix 2). The scale utilizes a 7-point Likert-type response scale ranging from 1 (strongly disagree) to 7 (strongly agree) (Cronbach’s α=0.86). A sample item of this scale is: ‘‘In most ways, my life is close to ideal’’. The total score is derived by summing all 5 items together, and the possible range of which is 5-35, with a score of 20 representing a neutral point, 5-9 indicating the extreme dissatisfaction with life and 31-35 indicating the extreme satisfaction.
5.3 Subjective happiness scale. The subjective happiness scale is a 4-item scale of global subjective happiness[42, 43] (Appendix 3). Each item is rated on a 7-point Likert-type scale ranging from 1 (strongly disagree) to 7 (strongly agree) (Cronbach’s α=0.89). Amongst, two of the items ask respondents to characterize themselves using both absolute ratings and ratings relative to peers, whereas the other two items offer brief descriptions of happy and unhappy individuals and ask respondents the extent to which each characterization described them. The total score is derived by summing the four items together. The possible range of the total score is 4-28, with a score of 18 to 22 representing an averaging range. The higher score reflects greater happiness.
5.4 Depression and anxiety scale. The symptom levels of depression and anxiety were measured by using the patient-reported outcome measurement information system (PROMIS)[44, 45]. PROMIS, which is a set of online measure systems developed by National Institute of Health (NIH) of United States (US), evaluates multiple physical and mental conditions, including anger, depression, fatigue, anxiety, depression and physical function measures[44, 45]. Both depression and anxiety questionnaires are a five item Likert-type response scale to measure the frequency with which respondents have experienced over the past week. Both of them are a universal symptom screening tool rather than a disease-specific diagnostic one. A sample item from the anxiety scale is: ‘‘I felt worried in the past seven days’’. Participants were asked to rate their agreement with 5 answer choices ranging from “Never” “Rarely” “Sometimes” “Often” to “Always” (Cronbach’s α=0.87). PROMIS has two different but highly comparable scoring options: short form and computer adaptive test (CAT)[46]. In the short form option, participants are asked to answer a whole set of questions, while the CAT is a response-based scoring system, in which participant’s response to the first item will guide the system’s choice of subsequent items, and the computer will calculate the sum score automatically[46]. We adopted the combination of both options: the participants were asked to finish the online CAT survey and the score from the CAT report were used for the current analysis. At the same time, they were also asked to answer a paper-version short form survey (12 item included, Appendix 4-5), to enable us know their response to each specific item. For both depression and anxiety in CAT, a score of 50 is the average for the general population. A higher score represents more of the symptom being measured.
6. Data analyses
The data were analyzed by using SPSS (version 18). Independent t tests were used to determine whether there were any differences between the pre- and post-test scores on each outcome measure. Estimated means were used to describe the averaged pre-test and post-test scores on the outcome measures. An alpha level of 0.05 was used to determine the statistical significance of all results.