A semi-structured interview method (43) was applied. The participants were invited to two interviews: one before the first NF training sessions (interview A) and one during the treatment course between session three and twelve (interview B). Open questions reflecting the objectives were asked followed by clarifying questions depending on the interviewee’s response. Three themes were examined in interview A: 1) thoughts and expectations, 2) acceptability, and 3) reservations and information needs. In interview B, the focus was on the following two themes: 1) satisfaction, and 2) feasibility and accept. Three participants (P2, P6 and P7) decided to withdraw from the quantitative substudy after only three completed NF training sessions. P2 left the study because he believed he could feel an electrical current going through his head during the training sessions, and P7 explained that for him, the NF treatment had resulted in severe nightmares. P6 did not think the first three NF training sessions had helped him, and he was convinced the completion of the remaining training sessions would make no difference. However, P2, P6 and P7 all agreed to take part in interview B. P1 did only participate in interview A and P8 did only participate in interview B. The number of completed NF training sessions before interview B is listed in Table 1. All the interviews were audiotaped and subsequently transcribed verbatim by the first author. Each interview lasted between 25 to 46 minutes and were all collected between February and May 2019 by the first author. All interviews were first translated to Danish, and all quotations have been translated from Danish to English.
Data was analysed by the first author together with one of the other authors (HLA). The analysis was carried out in four steps using a hermeneutic and phenomenological approach formulated by Dahlager and Fredslund (40), based on Gadamer’s and Giorgi’s philosophies (37–39). In Figure 2, the process of analysis is illustrated as well as the resulting four themes from the initial analysis. In order to identify the themes most illustrative for optimization of clinical practice, the data was reanalysed and recombined into new themes.
The data analysis finally resulted in three main themes capturing the essential aspects of both interview A and B, representing the participants’ reflections on the NF: 1) Positivity despite unfulfilled expectations 2) Understanding of the NF treatment 3) Facilitating factors for feasible NF treatment. The themes are closely related and intertwined and at some points overlapping.
Theme 1: Positivity despite unfulfilled expectations
The participants had several explanations and motivators regarding their willingness to participate in the study. All the interviewees expressed hopes and expectations that the treatment method could improve their mental health, and this was the overall reason why they agreed to try NF treatment. Naturally, they all wished that the treatment could bring relief to the symptoms that seemed to bother them the most in their everyday life. What was perceived as the most debilitating symptoms varied across respondents. P4 emphasized flashbacks and P1 pointed out concentration deficits. Both P2 and P6 mentioned their depressive symptoms:
"For instance, I expect and hope that my depressive moments and the thoughts about my past that interfere with my present thinking may get better. Improving this is what I hope and expect from the treatment." (P2, interview A)
Some of the interviewees had wishes that did not concern specific symptoms connected to their PTSD, e.g., P5 who wanted to get rid of her bad habits. When she was asked if there was something, she hoped the treatment to improve, she noted:
“Yes, of cause. I have some bad habits that I wish to change. For instance. I always bite my nails. And I’m always looking in my purse. These are the kind of things that I wish to change”. (P5, interview A)
An additional example was P7, who struggled with the fact that he very easily got emotionally affected when confronted with violence and torture on TV and the internet. He hoped the treatment could toughen him mentally, in this regard. In addition, many of the participants pointed out the novelty of the NF treatment to be a reason for trying it. In this regard, curiosity was a motivating factor. Words such as “exciting”, “interesting”, and “mysterious” were used by the participants to describe their reflections about the treatment. P6 expressed his initial thoughts about NF as:
“Mysterious and something new. You know, it makes you happy. A good feeling about it, and maybe it can help me? As you have mentioned, I have nothing to lose. I am taking the maximum dose of antidepressants right now; I cannot take any more medicine. And I have had so many psychotherapy sessions. But now I would like to take the chance.” (P6, interview A)
The quote illustrates the general tendency among the interviewees, that they have tried different types of treatments before NF, without sufficient effect, however. For that reason, they were very eager to get better, sparking a willingness to try anything, as exemplified by P1:
“As I have said, I would like to know more. I know that this treatment is going to help me. And even if it does not help me, at least I have done something. Because not doing anything is worse than doing something.” (P1, interview A)
P1 was convinced she would benefit from the treatment, which gave her a willingness and a drive to participate in the treatment. She thought that doing something about her problems was better than not doing anything.
Despite these promising expectations of the treatment, most of the participants reported in interview B that the NF treatment did not bring them relief of symptoms. The participants were asked if the treatment so far had met their expectations and except P3, all the participants who completed interview B, expressed disappointment regarding the treatment outcome, e.g. P4:
“My expectation was that it would change my mental state. But it hasn’t changed anything.” (P4, interview B)
As stated in the quote, P4 expected her mental state to change, but it did not and thus her expectations were not met. When P8 was asked directly, if the treatment matched his expectation, he declined. P6 explained that he had assumed he would feel an impact from the treatment, but he did not. Even though the participants did not benefit from the treatment, they could all agree on two things: 1) They believed that the treatment could help other trauma-affected patients and 2) They would recommend NF to others. As an example, P7, who expressed positivity and enthusiasm for the treatment program and encouraged the researchers to continue:
“I think it’s a really good program that you have started. I think you should continue the investigation. Maybe it is me, who has so much trauma with me. Maybe others could benefit. It is different how people react and what symptoms they have. “
(P7, interview B)
Even though P7 considered himself too traumatized to benefit from the treatment, he believed others could. The common idea among the participant that NF was recommendable and potentially helpful to others, indicated that even though NF was not a suitable match of treatment for them, the participants did have a positive view on the conduction of the training sessions and regarded NF as an acceptable form of treatment.
Theme 2: Understanding of the NF treatment
The second theme deals with the participants’ understanding of the NF treatment, including their ideas and expectations regarding the level of detail the NF device was capable of measuring. Even though the participants received the same information about NF (oral as well as written), they reported very different interpretations of what they imagined the NF training sessions would involve. P5 believed the NF treatment could treat the dysfunctional brain activity and correct harmful activity of the cells and tissue:
“It affects the activity in the brain and the tissue and cells. It corrects that activity.” (P5, interview A)
Similarly, P2 expected the NF equipment to provide information about his brain function in different states of mind:
“To find out how it looks when you are nervous, when you are scared, when you are happy. When you are in different states of minds” (P2, interview A)
When P7 was asked about his expectations of the treatment, he answered that he expected the NF training sessions to entail an examination of how his brain reacts:
“You explained to me, that you are going to examine how my brain reacts. That is how I have understood it.” (P7, interview A)
The quote demonstrates how many of the participants expected to get answers to questions about their brain function, and they believed the NF device made it possible for the therapists to reply to these questions in details. P1 expected the NF training sessions to involve her sitting in front of a screen, while the NF therapist investigates her brain:
“... And then he told me, that you sit in front of a screen and that you can see how stressed I am and what is going on in the brain. And I am looking forward to that. Because I really want to know why. “(P1, interview A)
P1 expected the NF training to result in her getting information about what happens in her brain and how stressed she was. Like P1, many of the participants were determined to figure out an explanation for their mental illness, and P1 was excited about the NF treatment because she believed it could provide her with the answers she needed. This reflects the common understanding of the capabilities of the NF equipment among the participants, believing the equipment allowed the NF therapist to examine the brain and investigate the functioning and dysfunction.
Theme 3: Facilitating factors for feasible NF treatment
Theme 3 emphasizes how different aspects of the NF treatment appeared to have a pivotal impact on the overall experience of the NF treatment. When the participants were asked what part of the NF treatment they valued the most, the breathing exercises stood out. All the participants found the exercises very useful, helping them relax and stay calm. P7 explained:
“You have taught me an exercise on how I should breathe. This has actually helped me, and I feel and sense of calmness in my body. To breathe this way calms me. I use this technique and it helps me - some nights if I cannot sleep, I use the breathing exercise, and then I feel calm.” (P7, interview B)
As demonstrated in the quote, the participants did not only benefit from the breathing exercises during the training sessions but also afterwards at home, e.g. to help falling asleep. Some of the participants experienced the exercises to be helpful throughout the day when exposed to stressful situations. P2 sometimes felt uncomfortable in school and he used the breathing exercise to calm himself:
“I do that too. And especially I do it when I feel restless and uncomfortable at school. (…) I do it at school and find it really helpful.” (P2, interview B)
Thus, to varying extents, the interviewed participants all learned to take home elements from the training sessions and managed to implement them into their everyday life as a coping strategy, helping them to handle their anxiety.
Aside from the breathing exercises, another decisive factor was the physical attributes of the training environment. In the beginning of the study, the NF training sessions took place in a small room (approx. 6-7 sqm) with relatively dim lighting. After a couple of months, the treatment was moved to a bigger and well-lit office space (approx. 20 sqm) overlooking a garden. Without exception, all participants considered the size of the room to have a significant influence on the atmosphere, and when asked directly, they all preferred the new and larger room. P6 did not understand why, but he felt a pressure on his chest when he was in the smaller room:
“Yes, the size of the room. I do not get it, I do not understand what it is. It is like, there is pressure on my heart.” (P6, interview B)
In the same way, P4 felt cramped in the small room and found it too dark. It reminded P3 of torture and the larger more spacious office calmed him down. He explained his thoughts using the following words:
“Last time, it was a small room. And then it was like, you remembered the torture. But in the room we are in now... there is more space. It calms me down” (P3, interview B)
This calming effect of the bigger room as well as the breathing exercises illustrated how different components of the NF training sessions affected the participants’ state of mind. Another element was the music used as the auditory part of the feedback signal during the NF treatment. P6 was surprised how much this music affected his mood. He suggested the NF participants should be allowed to pick a music genre themselves, in order to make sure the music did not make them uncomfortable or reminded them of something unpleasant. P6 proposed the same procedure when selecting the videos used for the NF training. He emphasized the importance of the therapist knowing details about the participants’ background, in order to adjust the content of the videos to the individual, e.g. someone who had lost a child would not like watching videos of children:
Yes, I would like some better pictures. And more realistic – actually, just as realistic as possible. Nature or something like that. And maybe you should ask the participants about their background, because someone who has lost a child, would not like to have shown pictures of children. I think you need to be specific. You need to be more individual and ask the participants the question: What makes you happy? (P6, interview B)
Similarly, P8 emphasized the importance of choosing the right video to avoid evoking uncomfortable memories and harming the participant. He encouraged the NF therapists to consider what thoughts and feeling the videos could possibly induce for the participant:
Maybe it would be wise to pay attention to the movie clips and pictures, showed during the training sessions. How they can possibly bring back old memories for the patient. You have to choose something that does not harm or create a wound. The therapists ought to consider whether the movie clip will create happiness or grief for the patient. E.g., if I hated the colour red, don’t show a picture with red colours.” (P8, interview B)
According to the participants, this idea of tailoring the NF treatment for each individual participant would allow the NF therapist to take care of the participants’ needs the best possible way.