According to the World Health Organization, every year about 700,000 people die by suicide [1]. Suicide is one of the most severe public health problems in the world. The high number of suicides in Japan has been a national issue since it transcended 30,000 per year in 1998 [2]. The number of suicides in 2020 was 21,081, an increase of about 4.5% compared to 2019 [3]. Although the number of suicides and suicide rate are declining compared to historic peak times in Japan, the Japanese suicide rate is the 5th highest among Organisation for Economic Co-operation and Development countries; additionally, the Japanese suicide rate is the highest among all Group of 7 (G7) members [4].

Furthermore, suicide was the leading cause of death among individuals aged 15 to 39 years in Japan [3]. This situation in Japan is serious, and among all G7 members, it is only in Japan that the leading cause of death among youth aged 15 to 34 years is suicide [5]. Suicide is the leading cause of death for college and university students in Japan [6]. Therefore, suicide prevention measures for young people, especially students, are urgently needed.

Recently, COVID‐19 has spread throughout the world. Problems associated with outbreaks of infections such as COVID-19 have an undesirable impact on learning and can also lead to mental health problems [7]. The effects of COVID-19 on the already-high suicide rate create an urgent need to deal with suicide among youth, especially students. A previous study showed that about 80% of college students who died by suicide had no prior contact with campus mental health professionals, and 85% of college students with moderate to severe depression did not get treatment [6,8]. Considering this fact, it is possible that students who have mental health problems cannot take measures by themselves (ie, help-seeking) or are not aware of the severity of their own condition. Therefore, awareness by other persons, such as gatekeepers who can detect and refer at-risk individuals, is essential for students experiencing difficulties.

A gatekeeper is someone aware of the signs of suicide who can take appropriate action (ie, be aware of people in need, speak to them, listen closely to them, direct those in need to resources for support, and watch over them) [9]. Gatekeeper training (GKT) is a program to foster the development of gatekeepers and aims to help nonprofessionals identify and respond to those at risk of suicidal behavior; it is the most general intervention in suicide prevention [10]. GKT programs are a generally recommended suicide prevention intervention in Japan, and the Japanese government and all local governments in Japan presently conduct GKT in various forms [11]. GKT builds the self-efficacy of those acting as a gatekeeper, such as speaking to people at risk of suicide. A recent meta-analysis in the United States reported the effectiveness of GKT in universities on suicide prevention knowledge, skills, and self-efficacy [12]. Thus, increasing a student’s self-efficacy as a gatekeeper leads to more gatekeeper actions and, as a result, suicide prevention.

Students, however, may encounter obstacles in attending a GKT program. The most significant hurdle for students may be a lack of time and resources to participate in face-to-face training sessions. In addition, GKT programs conducted at a school or in a class unit often involve familiar acquaintances, and as GKT also includes private content such as sharing experiences and opinions in group work, some may not want to participate due to privacy concerns. As such, on-demand online GKT programs may be helpful in overcoming such hurdles for students. On-demand online GKT provides easy, fast, instant, and privileged access to needed knowledge about student suicide prevention at any time and from any location.

Most university GKT programs focus on teachers and related staff (eg, school counselors, nursing teachers) because of their daily interaction with students [13]. However, students have more opportunities to interact with other students than faculty members. Students may feel it is more challenging to talk to faculty staff than to other students (acquaintances). Suicidal college students tend to seek help from friends and family rather than from a mental health professional [14]. Past studies have shown that college students are most likely to talk to friends about suicidal ideation or ask for treatment when recommended by a friend [15,16]. Hence, students are especially advantageous as gatekeepers. GKT tailored to students is needed to increase the number of student gatekeepers.

Few programs have reported on the effectiveness of GKT programs for decreasing the number of suicides. Most studies have reported on suicide knowledge, attitudes, and skills of trainees instead of the number of suicides [17,18]. It is difficult to evaluate the effectiveness of GKT programs based on a decrease in suicide attempts or suicides. Therefore, in this study, we decided to use a surrogate outcome.

Behavior as gatekeeper has been conceptualized with the theory of planned behavior (TPB) [19,20]. According to TPB, “attitudes toward the behavior” may be our thoughts about the potency of, and our emotional reaction against, conducting the behavior [21]. TPB shows “perceived behavioral control” is the perceived controllability of a specific behavior, including a person’s understanding and ability to perform the behavior [21]. These affect “intention to intervene” and lead to actual actions [21].

We hypothesized that self-efficacy as a gatekeeper affects attitudes toward the behavior and perceived behavioral control from this theory, leading to actual behavior as a gatekeeper. Past research has reported that GKT programs have improved self-efficacy as a gatekeeper [22-25]. Furthermore, self-efficacy was chosen as the primary outcome in this study because we thought self-efficacy in attitudes has the most significant impact on behavior among the commonly used surrogate items (knowledge, attitudes, and skills).

Assuming that encouraging action for suicide countermeasures as a gatekeeper lowers the suicide rate, a GKT program was created aimed at increasing self-efficacy, which affects behavior as a gatekeeper based on the attitude of TPB.

To date, to the best of our knowledge, there has been no online GKT program for students in Japan. Moreover, no randomized controlled trials (RCTs) have been conducted to verify the effectiveness of online GKT programs for students. Accordingly, the aims of this research are to (1) create an online peer GKT program for students and (2) verify its effectiveness through RCTs.

Figure 1 shows the participant flow and study design. This study will be a 2-arm parallel-group nonblinded RCT with a GKT intervention group and a waitlist control group. Eligible participants are required to complete the baseline survey (t₀) and are randomly allocated at a 1:1 ratio either to the intervention group or the control group. All surveys will be conducted via online questionnaires. Online follow-up surveys will be implemented about 10 days after the t₀ survey (t₁: immediately after the intervention), and at 2 months after the t₁ survey (t₂). After the 2-month follow-up, the GKT program will be provided to participants in the control group who wish to attend. This manuscript has been written according to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines [26].

This study will target postsecondary school students (eg, college and university students) in Japan. The inclusion criteria for individuals will be students aged 18 to 29 years, in Japanese postsecondary school, with access to the internet via their own PC, smartphone, or tablet, and who acknowledge the program offered is a suicide prevention program. The exclusion criteria will be students who cannot read and write Japanese or who are full-time workers. The researchers asked their acquaintances to publicize this study through the mailing lists of their institutions. We also used social networking sites, our websites, and flyers to inform this study.

Candidates will click the URL provided in the information about the invitation for GKT research and read a full explanation of the purpose and procedures of the study on the website. Students who are interested in participating will be asked to mark the consent option and type their name and their email address to give their consent. This consent information will be sent to the research center and preserved. Students who are not interested in participating will be asked to leave the website. Subsequently, participants who submitted the consent information will complete the baseline survey. After completing the baseline questionnaire, participants will be randomly assigned either to the intervention or the control group. Researchers will inform participants of their group assignment and send an email containing the GKT program’s homepage URL and password to participants in the intervention group. Participants in the intervention group will click the URL, enter the password, and receive the GKT program. They will be asked not to share this URL, password, and the GKT program content with others. Participants in the intervention group will be instructed to take the program within 10 days of receiving notification of group assignment. t₁ surveys will be administered to both the intervention and control groups. Participants in the intervention group are instructed to complete the t₁ survey immediately after attending the program. Participants in the control group are asked to respond to the t₁ survey 10 days after the t₀ survey. Those in the control group will receive the GKT program after the t₂ survey. Participants who answer all 3 surveys will get the chance to win a ¥1200 (US $10.14) gift card from Amazon as a monetary incentive to promote retention and follow-up completion by lottery.

We developed a new GKT program using the following steps. First, we decided upon the composition of the program content by referring to existing GKT programs and the role of the gatekeeper advocated by the Ministry of Health, Labor, and Welfare. The first author then developed a preliminary program in consultation with researchers specializing in psychiatric nursing and psychiatry and in collaboration with experts in suicide prevention from a Japanese nonprofit organization. Next, the first author conducted a feedback session with 5 students and modified the program according to their recommendations. Last, a pilot trial was performed with vocational school students nested in one organization (n=18). Additionally, an opinion exchange meeting was held at the workshop for people involved in mental health and welfare to watch a part of the GKT and give their impressions. Based on these opinions and the results of the pilot trial, we modified the program and created the final version of the GKT program. The final version of the internet-based GKT program designed for postsecondary students was developed (Figure 2). The home page of the GKT program is the platform for participants to access the program. The content of this homepage includes an explanation of how to use the GKT program, videos of the GKT program (sections 1-6) via YouTube, a comment section (online discussion board), a text download page, and a contact form to the administrator. The videos of the GKT program consist of the following 6 sections for a total of approximately 85 minutes (Table 1). The GKT program covers mental health basics (section 1), current status of suicide problems (section 2), danger sign features of suicide (section 3), how to appropriately respond (section 4), demo video (section 5), and referral information for appropriate resources (section 6). Each section takes 10-20 minutes to view and contains a voiceover, cases, personal work, and quizzes (except for section 5). We made videos of the GKT program for uploading to YouTube. Sections 1-4 and 6 were created by us in PowerPoint with lecture-style videos. Section 5 was shot with a video camera and edited with video editing software. The GKT program introduced a demo video (section 5) instead of role-playing. The demo video shows how to respond in situations students are likely to experience, and participants can learn how to respond concretely by imagining the characters appearing in the examples and replacing them with themselves. These are online videos but are unlisted and restricted to people who have the link to the video so only participants in the intervention group and researchers can view them. Because they are played on YouTube, the modules were designed so the participant controlled every aspect of the module, such as skipping or replaying a movie, adjusting playback speed, and switching the voiceover or subtitles on or off. Of course, during the intervention period, participants could watch the video at any time and place. Participants are instructed to watch sections 1 to 6 in order. Furthermore, participants have access to an online discussion board on the website, which gives them the opportunity to exchange thoughts with each other. On this online discussion board, participants can browse other participants’ ideas and write their own opinions, but cannot reply to other participants’ comments.

This GKT program does not have homework and is fully self-guided. However, participants are encouraged to voluntarily comment on their personal work responses and section impressions and read the opinions of other participants. Participants can download the text used in the videos of the GKT program on this homepage. In each section, an announcement is made to stop watching the video if they feel uncomfortable. The pages in each section provide a list of contacts available if they feel unwell.

Table 2 summarizes the outcome measures. Only the participants in the intervention group are assessed regarding the process evaluation outcomes (eg, usability, satisfaction) at the t₁ survey. All data are collected using web-based self-report questionnaires. At the t₁ and t₂ surveys, the researcher (KN) will send at least 2 emails reminding nonrespondents to complete the questionnaires.

The sample size calculation is based on the difference between means of change in the primary outcome (self-efficacy as the gatekeeper) from baseline (preintervention) to postintervention (t₁ survey) in both arms (complete case analyses). Based on previous studies on GKT, mean effect sizes of around d=0.5 are expected in per-protocol analyses for improving self-efficacy [12,22-25]. In order to detect such intervention effects in 2-tailed significance testing (α=.05) with a power of 80%, a sample size of 64 per group (total 128) participants is required. We assume the study dropout rate will be higher in web-based intervention and assessments compared to face-to-face research. The expected study dropout was about 60% (dropouts occur at random within each group), and this meant that 320 participants (160 per group) must be included in the study.

After baseline assessment, participants will be randomly assigned to either group using the permuted block method with a random block size of 2, and they will be informed of their assigned group by the first author (KN). Randomization will be stratified by sex. The computer-generated allocation list was made by an independent researcher (YM). The enrollment is conducted by the first author (KN), and the intervention starts immediately. The means for blinding in this study are limited. An independent researcher (YM) who will not analyze data will download data from the GKT database. An independent research staff person will mask the group variable before analysis, and then researchers (KN) will analyze data that is blinded to the group variable.

The primary analysis for the GKSES score will be on a modified intention-to-treat principle, in which all available measurements are compared according to assigned groups. Baseline variables will be summarized by the groups using frequencies and proportions (for categorical variables) or mean and standard deviation (for continuous variables). The primary end points (difference of GKSES total score between presurvey and postsurvey) between the intervention group and the control group will be compared based on a t test. We will set the 2-sided significance level at 5%, and the 95% confidence interval of the average difference in differences of the scores will be estimated. Secondary end points will be compared similarly. As subgroup analysis for primary and secondary end points, we will stratify by highly dependent and lesser dependent groups for internet use, a group with high fear of COVID-19 and a group with low fear of COVID-19. To help interpretation, Cohen d and its 95% confidence intervals will be calculated at each assessment point; the values of 0.2, 0.5, and 0.8 are considered as small, medium, and large effects, respectively [38]. Statistical analysis will be performed using SPSS (version 27, IBM Corp) statistical software.

This study does not have an external data monitoring committee. The first author (KN) will manage participants’ progress and completion of the intervention and the follow-up assessments.

The Ethics Committee of the Faculty of Medicine and Graduate School of Medicine of the University of Tokyo approved this study (2020234NI). Before the baseline survey, candidates will be fully informed that their participation is totally voluntary and they can withdraw consent if they want (they can send a withdrawal email to researchers). Informed consent by an explanation in the document will be conducted, and the marked consent option and full name will be obtained from all participants. Even if participants withdraw consent, they will not receive any disadvantage. In addition, they will be informed that the findings of this study will be disseminated without participants’ personal information via publication and website. The participants will be told that the web-based program does not provide emergency support on the website and will be provided with corresponding contact information that can be used in case of emergency during the program. All data collected in this study are securely stored without the participants’ personal information. Access to the data is encrypted and limited to research staff named on the ethics protocol. This study protocol was registered with the University Hospital Medical Information Network Clinical Trial Registry [UMIN000045325]. If there are important modifications of the protocol, we will obtain approval for the modifications from the Ethics Committee of the Faculty of Medicine and Graduate School of Medicine of the University of Tokyo and will revise the protocol on the trial registry website.

Collected data will be stored as linkable anonymized data. The principal investigator will retain access to the final dataset after the trial and assume responsibility for data integrity and accuracy of the analysis.

The first author conducted informal discussions with 5 students and nonprofit organization representatives that implement youth suicide countermeasures. Based on these conversations, adding 2 researchers to those mentioned, we modified the contents to reflect a real situation. One patient and public involvement (PPI) partner, a college student, reviewed the program’s draft and noted some points that might be difficult for general students to understand. These PPI partners will participate in a discussion of the study results and in making the implementation strategy after finishing the RCT. We described the PPI process based on the PPI handbook and reporting checklists.

We hypothesized that the online GKT program for students will increase self-efficacy as a gatekeeper. Moreover, we hypothesized that self-efficacy as a gatekeeper affects attitudes toward the behavior and perceived behavioral control from TPB, leading to actual behavior as a gatekeeper.

The effects of an online gatekeeper program on self-efficacy will be examined for gatekeepers among postsecondary students in Japan. To the best of our knowledge, this study is the first RCT to examine the effectiveness of online GKT programs without face-to-face sessions targeting students rather than staff or faculty for their self-efficacy as gatekeepers. This online program will allow individuals to participate without worrying about their privacy anytime, from anywhere.

An online GKT program requires less involvement by mental health specialists such as public health nurses. It can be provided at a low cost in a low-resource setting in which trained practitioners are seldom available. Thus, this online GKT program has much potential for dissemination as a practical tool for the prevention of suicide in schools such as universities. Once we find the online GKT program sufficiently effective, it will contribute to the dissemination of gatekeeper online training to a large number of students to prevent suicide at a low cost and, as in the COVID-19 era, where close social contact is limited.

The main findings of this study will be disseminated via publications in peer-reviewed international journals. Study findings will also be presented at scientific conferences.

Due to the intervention’s nature, it is not possible for both the intervention implementer and participants to be blinded to group assignments. Because all the outcomes in this study will be obtained by the self-reported questionnaire, information bias could be introduced. Generalizability will be limited because snowball sampling will be used instead of random sampling.

This is the first study to investigate the effectiveness of an online GKT program for students to improve self-efficacy as a gatekeeper using an RCT design. The study explored the potential of an online peer gatekeeper program for students that can be disseminated online to a large number of students with minimal cost.