Nursing students are typically provided a nursing syllabus that requires study or training, as well as professional values and ethics. This means working independently and persistently, with full dedication toward the profession [1], and with credible legal autonomy. The nursing profession refers to a career of service, responding to the health needs of society at the level of the individual, the family, and the community, in scenarios of both sound health and illnesses [2]. The objectives of the nursing profession consist in the provision of care, assistance, rehabilitation, disease prevention, and the promotion of health, including assisting a physician in the treatment of disease, all of which depend on the application of specialized nursing knowledge [3]. In studying for the nursing profession in Thailand, students begin their practice during the second semester of their second year of undergraduate education and continue to practice in their third and fourth year. The students practice three days a week in a hospital [4]. After high school students have graduated, they can apply to nursing school, where they will study basic science, for example fundamental anatomy and fundamental biochemistry in the first year. In the second year, the nursing students have to continue to study basic nursing science during the first semester and practice the fundamentals of nursing with patients in the hospital during the second semester. The third year, they begin to study and practice specific areas of nursing science, such as mental health and psychiatric nursing, community health nursing, and nursing for the family and midwifery. At the end of their studies, fourth-year students practice in the hospital more than they study in the classroom and must pass nursing competency assessment and a licensing examination [5].

Stress poses an obstacle to concentration in problem solving and decision-making, and obstructs other necessary abilities and is thus a serious factor in terms of students’ learning [6]. There is now evidence that makes it unmistakably clear that students are under a great deal of stress from their programs of study in the health professions, which can adversely affect their health as they study [7]. As an example, it has been found that more than half of clinical-class nursing students between their second and fourth years of study are severely stressed. Nonetheless, it has been found that 24.5% of students with scores at an abnormal level from screening were suffering from depression [8]. Furthermore, it has been found that nearly one in every three students enrolled in the public-health sciences have moderate stress levels [9]. As regards those students that are studying in the nursing professions, it has been found that they experience stress levels at a higher level than students enrolled in other branches of the health sciences [10]. In fact, it has been suggested that the stress imposed on nursing students in many universities is greater than the stress borne by all other university students [11]. In addition, it has been found that some nursing students, third-year nursing students in particular, time to time have had to deal with a lot of problems that impact their mental health [12]. Further, studies of the stresses imposed upon first-year nursing students have shown that these students experience high stress levels. The same studies also show that the stress borne by nursing students is not related to the methods of stress management currently being used [13]. A possible explanation is that those with high stress levels are continuing to use methods of stress management that are inappropriate, so that they are not able to manage their stress as much as they should. Consequently, their stress levels remain high. Students that use proper problem-solving methods, on the other hand, succeed in reducing their stress loads. These outcomes are in agreement with a previous study, in which it was found that student stress was not related to confronting stress [14].

There are many causes of stress in nursing students. From a study conducted by Shaban et al. [15] it was found that the causes of stress in nursing students were rooted in their learning environment, especially in the work that was being assigned to them in the various subject areas of their study. As regards the cause of stress in Thai nursing students, it was found that it was their nursing coursework, and especially courses in the practice of nursing that were creating this stress [16]. These students did not yet understand the system of work applicable to the field of nursing; nonetheless, they were being quizzed by their instructors to determine how much they knew already. This impact was being especially felt by nursing students that were entering the field of practical nursing for the first time [17]. It was found that there was stress from performing procedures and becoming prepared with the necessary knowledge for use in the patient wards. They felt stressed from the patient-ward environment and from their need to connect and communicate with the senior nurses, and the patients and relatives of the patients. They were forced to endure stress from having the role of instructor in the patient wards and from the effect it was having on their own states of health and on their living [18].

There are many ways to reduce stress. In one study, it was found that enhancing the imagination took place in conjunction with a cognitive and behavioral-therapy program, in which it was found that there are many ways of easing stress, each of which can effectively lower the stress load being borne by an individual [19]. Imagination uses the ability of the subconscious to imagine for example a peaceful natural fantasy or natural images where the practitioner finds herself or himself in a relaxing and peaceful body. While imagining images, the practitioner should breathe evenly and deeply, and focus on the details of the images created, such as their colors, sizes, texture, sounds, odors, and surroundings. When other ideas interfere, the practitioner should draw her or his attention back to those details [20]. Sriwatanakul [21] stated that relaxation through the use of imagination techniques (autogenic training) is an applied science derived from the principle of hypnosis of Dr. Schultz, which he first developed in 1932. It is useful for improving concentration and memory, increasing the efficiency of work, and limiting worry and anxiety. Similarly, Ruchiwit [22] stated that the imagination is important and influences the control of our feelings and behaviors in carrying out our daily lives. Our thoughts and imaginations are factors that stimulate our emotions. Our imaginations are creative and can quell our emotions and make us feel comfortable. Emotional stress energy flows with ease, helping the muscles in all of the organs to relax so that a state of calm or relief can then follow, making the body ready to adopt any of various recommendations. Similarly, Saengduenchai [23] stated that methods of mind training and meditation practice should be applied for use in cognitive and behavioral therapy in order to encourage awareness of one’s thoughts and problem-solving ability based on the use of the mind. Such methods have an important use in the cognitive and behavioral adjustment of a person, causing a person to acquire a degree of behavioral durability [24]. The various methods of relaxation, including muscle relaxation, enhancing the imagination, meditation practice, etc., help to abate the tenseness of the emotions within the central nervous system and induce the limbic brain system to become less stimulated. Emotional stress is thus reduced. The affected individual then feels better, both psychologically and physically. This can be accomplished conveniently and without expense [25].

In addition, enhancing the imagination is a traditional method to reduce stress when facing individuals or groups. However, the COVID-19 pandemic has affected a variety of social causes and many countries have decided to temporarily close schools, affecting millions of students [26]. In Thailand, the government’s Department of Education has come up with guidelines to implement online and modular distance learning delivery of instruction. Moreover, according to one study, Internet usage was proportionately higher in the teenage and young-adult group, who were 15-24 years of age, than in any other group and this increased from 39.7% in 2007 to 51.9% in 2011 [27]. According to these statistics, smart phones are an important convenience for nursing students 18 to 22 years of age in their day-to-day living; their phones for example can load the imagination-enhancement app [28].

The objective of the present study was to investigate the effectiveness of a program for enhancing the imagination through the use of a mobile app in order to ease nursing students’ stress loads.

2.1. Conceptual Framework of the Research

From studies conducted and theory and documented research that were relevant to this study, it was possible to examine the influence of the stress-management program on nursing students. The program was based on enhancing one’s imagination to the point of relaxation through the use of imagination techniques. The conceptual framework of the research is illustrated in Fig. (1).

Fig. (1). The conceptual framework of the research.

This study on the effect of a program for imagination enhancement through use of a mobile app on the stress loads of nursing students took the form of an experimental research, which was carried out with two groups and using a repeated measures design at each of three stages, namely, pre-experimentation, immediate post-experimentation, and two-weeks post-experimentation. The participants were subdivided into an experimental group, which took part in the imagination enhancing program through the use of a mobile app, and a control group, which received an information sheet on stress management from the mental health clinic of Thammasat University Hospital.

3.3. The Instrument used in Conducting the Tests

The program for enhancing imagination was developed by the researchers and validated by a specialist in mental health nursing. The use of a mobile app was developed using techniques and imagination in order to stimulate an emotional state and to induce change in the muscular system. Enhancing the imagination provides a release for the emotions and a pleasant feeling, and as stated earlier. An audio recording was made of the imagination-enhancement program and was installed in the Mind-Counseling application using the following procedure.

Quality monitoring of the imagination-training program using the mobile application included determination of its content validity by three qualified persons: two psychiatric nursing instructors and one educational technology expert. The determined index of item-objective congruence (IOC) of 0.82-1.00 met the accepted criterion of 0.50 or higher [29]. Recommendations by the qualified persons were implemented for improvement and were tried out.

How to practice program enhancing the imagination by the Mind-Counseling application

1. Install the Mind-Counseling application in the mobile devices of the volunteer participants in the experimental group, using both the iOS and Android operating systems.

2. Enter the Mind-Counseling application and, from there, subscribe new members.

3. Supply the following requested information completely. Then select “I have entered all information.”

4. The system will lead the volunteers to the first page of the program, which will allow you to choose the menu Those times when I am happy.

5. Set a time and notification message to devote a block of time to the enhancement of your imagination, which you will be practicing every day, once a day, for about 10-15 minutes. Then select: “Confirm Notification.”

6. When the specified time arrives, the system will alert you on your mobile device. You will then enter the Mind-Counseling application. On the first page, select “Stress-relief practice by myself.”

7. At this point, begin practicing the enhancement of your imagination. Continue to practice it for 14 days in a row.

The research findings have enabled a discussion on the effectiveness of the program of imagination enhancement through the use of a mobile app on easing nursing-student stress loads. The relevant issues were as follows.

The present study employed a stress-measurement testing device intended for the people of Thailand known as the Thai Stress Test. The defined scale levels are: never feeling stressed, feeling stressed occasionally, and feeling stressed quite often. The test itself consists of multiple-choice questions to which the respondent chooses the answers that match her or his feelings in the moment. It is divided into two sections: questions 1-12 refer to feelings of negativity, and questions 13-24 refer to feelings of positivity. Viewing the specifics of the present study as a division between feelings of negativity and feelings of positivity shows that feelings of negativity before, just after, and two weeks after the conclusion of the program for imagination enhancement differed with a statistical significance of 0.05. This value applied to comparisons both within the experimental and control groups, as well as to comparisons between the two groups. Such are the results obtained from the program on imagination enhancement, which sought to train the experimental group members to use their imaginations to develop a sense of internal peace and happiness, and which should be helpful to the experimental group in reducing whatever feelings of negativity they may be experiencing.

These findings are in agreement with the research results obtained by Kanji et al., who introduced the technique of autogenic training for use in lowering the stress loads of 93 nursing students studying at a university in the United Kingdom. They found that they could lower the stress loads of the nursing students significantly. Furthermore, they were able to lower their blood pressures and heart rates as well [30]. Their technique was based on muscle and breath control, along with imagining a place of peace and contentment. Their work harmonized with the research work of Lim and Kim, who conducted a study of the effect of enhancing the imagination for the purpose of reducing stress and heart rates of 40 nursing students that were in the third year of their studies at two universities. It was found that the stress loads were lowered significantly, while heart rates were not significantly reduced [31].

The mobile application is a communication medium for use in a program for stress-relaxation practice, which is based on autogenic training. It is capable of reducing stress, since it is compatible with the sample group of teenagers and young adults, most of whom are in the habit of using their cell phones for more than four hours each day [32]. This proved to be an alternative way of easing stress, apart from other methods. Its usage features are consistent with the results of a study that proposed a mobile app for easing stress; the app was used in a sample group of 30 people for a period of four weeks and it was found to be capable of reducing stress significantly [33]. Yet, it was found that the average values of the experimental group, whose members were using the program, had increased at two weeks after the conclusion of the program (M = 9.04, SD = 4.38) and were then beyond what they had been when the program had just ended (M = 0.11, SD = 4.16). It is possible, therefore, that after a certain amount of time, stress levels can increase again. Similarly, in a study conducted by Hwang and Jo, it was found that after four weeks, stress levels had increased beyond what they were at the very end of the program [34]. These findings were further verified by a systematic literature review of a study that examined the results of using a mobile app in a sample group that had been afflicted with post-traumatic stress disorder. It was found possible to reduce stress, but there were limitations imposed by the length of time that had elapsed since concluding the experimentation. The stress levels would then rise again [35].

The fact that the stress levels could rise again is only one matter of concern. Use of the Mind-Counseling application requires the payment of a fee in order to download it onto the cell phone where it can then be installed. The price will depend on the service fee of the sample group using it [36] and the memory limitations of the cell phones used by the sample group. It would therefore be necessary to erase some of the data stored in the phones in order to install the program. It was also found that when the members of the sample group in the present opened their phones to run the imagination-enhancement program, there were sometimes other notifications disrupting their practicing. This situation was mirrored in a study on running programs on a cell phone. The study was aimed at reducing anxiety when a notification from a game loaded in the phone interrupts the practice of the sample group yet again [33].

• This study focused on only one nursing school in order to make the teaching program the same for the experimental and control group.
• Most of the samples were female nursing students because in Thailand nursing is more popular among females than males.
• In order to achieve the necessary sample size, the nursing students in all years were included in the study because there were not enough students that exhibited mild stress in each year alone.

The findings of the present research illustrate the practical use of technology in providing care for nursing students that are under stress, and that are able to adapt to real-world situations and have aptitude in the use of technology. This technology can therefore be effectively applied to the mental healthcare of nursing students.