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CLINICAL RESEARCH ARTICLE
Experiences with a guided trauma-focused internet- and mobile-based
intervention: a qualitative study of youth’s perspectives
Christina Schulte
a
, Cedric Sachser
b,c,d
, Rita Rosner
e
, David Daniel Ebert
a
and Anna-Carlotta Zarski
a,f
a
School of Medicine and Health, Professorship Psychology and Digital Mental Health Care, Technical University of Munich, Munich,
Germany;
b
Department of Psychology, Professorship Clinical Child and Adolescent Psychology, University of Bamberg, Bamberg,
Germany;
c
Department of Child and Adolescent Psychiatry/ Psychotherapy, Ulm University, Ulm, Germany;
d
German Center for Mental
Health (DZPG), partner Site Ulm, Ulm, Germany;
e
Department of Psychology, Catholic University Eichstaett-Ingolstadt, Eichstätt, Germany;
f
Department of Clinical Psychology, Division of eHealth in Clinical Psychology, Philipps University of Marburg, Marburg, Germany
ABSTRACT
Introduction: Research on internet-interventions for youth with post-traumatic stress
symptoms (PTSS) is limited, despite promising results in adults. A non-randomised feasibility
study of a therapist-guided trauma-focused internet- and mobile-based intervention (IMI)
showed potential in reducing PTSS but revealed challenges with adherence and individual
fit. Insights from qualitative studies can enhance intervention quality by addressing personal
needs. This study explores participants’ views on the feasibility of a therapist-guided
trauma-focused IMI to improve digital trauma interventions.
Methods: Semi-structured interviews based on theoretical models of acceptance and human
support in IMIs were conducted with 17 of 32 participants from a self-help-based trauma-
focused IMI with therapist guidance. Audio-recorded interviews were transcribed and
analyzed using deductive-inductive content analysis. Independent coding resulted in good
agreement (κ = .76).
Results: 20 themes were identified and organised under nine dimensions: participation
motivation and expectations; recruitment process; treatment adherence and everyday use of
therapeutic exercises; trauma processing; non-trauma processing intervention components;
technology, structure, and design of the IMI; human support; individual fit; and active
factors and ecacy. The technology, structure, and design of the IMI and other non-trauma-
focused components were rated positively. Trauma processing presented challenges for
many but was still perceived as a helpful and relevant active factor. Some felt a lack of
therapeutic support, and greater personalisation of guidance was a frequent suggestion for
improving the individual fit. The IMI’s ecacy was most often perceived in its eects on
improved coping with trauma and symptoms.
Discussion: The study identified key themes for the feasibility of a trauma-focused IMI for
youth, showing general acceptance of its design, structure, and technology. While trauma
processing in IMIs poses challenges similar to face-to-face therapy, these can be addressed
by clarifying the therapy rationale, making trauma processing an important active factor.
Further research is needed to improve individualisation and therapeutic support intensity.
Trial registration: German Clinical Trials Register identifier: DRKS00023341..
Experiencias con una intervención guiada por Internet y móvil centrada
en el trauma: un estudio cualitativo de las perspectivas de los jóvenes
Introducción: La investigación sobre intervenciones en Internet para jóvenes con síntomas de
estrés postraumático (PTSS por sus siglas en inglés) es limitada, a pesar de los prometedores
resultados en adultos. Un estudio de viabilidad no aleatorizado de una intervención basada
en Internet y móvil (IMI, por sus siglas en inglés) centrada en el trauma y guiada por un
terapeuta mostró potencial para reducir el PTSS, pero reveló dificultades con la adherencia y
la adaptación individual. Las reexiones de los estudios cualitativos pueden mejorar la
calidad de la intervención al abordar las necesidades personales. Este estudio explora las
opiniones de los participantes sobre la viabilidad de una IMI guiada por un terapeuta y
centrada en el trauma para mejorar las intervenciones digitales en el trauma.
Métodos: Se realizaron entrevistas semiestructuradas basadas en modelos teóricos de
aceptación y apoyo humano en IMIs con 17 de 32 participantes de una IMI basada en la
autoayuda y centrada en el trauma con orientación de terapeutas. Las entrevistas grabadas
en audio fueron transcritas y analizadas usando análisis de contenido deductivo-inductivo.
La codificación independiente resultó en una buena concordancia (κ = .76).
ARTICLE HISTORY
Received 21 October 2024
Revised 17 February 2025
Accepted 4 March 2025
KEYWORDS
Trauma; post-traumatic
stress disorder; adolescents
and young adults; internet-
and mobile-based
intervention; trauma-focused
cognitive behaviour therapy;
written-based exposure
therapy; qualitative analysis
PALABRAS CLAVE
Trauma; trastorno de estrés
postraumático; adolescentes
y adultos jóvenes;
intervención basada en
Internet y móvil; terapia
cognitivo-conductual;
terapia cognitivo-conductual
centrada en el trauma;
terapia de exposición basada
en la escritura; análisis
cualitativo
HIGHLIGHTS
• Youths’ perspectives on
taking part in a feasibility
study evaluating a digital
trauma-focused
intervention are examined.
• The digital trauma-focused
intervention was generally
accepted in terms of
design and content.
• Youth highlighted various
themes for improving the
intervention including the
level of guidance and the
degree of personalisation.
© 2025 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which
permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. The terms on which this article has been
published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.
CONTACT Christina Schulte christina.schulte@tum.de School of Medicine and Health, Professorship Psychology and Digital Mental Health Care,
Technical University of Munich, Georg-Brauchle-Ring 60, 80992 Munich, Germany
Supplemental data for this article can be accessed online at https://doi.org/10.1080/20008066.2025.2480040.
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY
2025, VOL. 16, NO. 1, 2480040
https://doi.org/10.1080/20008066.2025.2480040
Resultados: Se identificaron 20 temas organizados en nueve dimensiones: motivación y
expectativas de participación; proceso de reclutamiento; adherencia al tratamiento y uso
cotidiano de los ejercicios terapéuticos; procesamiento del trauma; componentes de la
intervención no centrados en el trauma; tecnología, estructura y diseño de la IMI; apoyo
humano; adaptación individual; y factores activos y eficacia. La tecnología, la estructura y el
diseño del IMI y otros componentes no centrados en el trauma fueron valorados
positivamente. El procesamiento del trauma presentó desafíos para muchos, pero aún así se
percibió como un factor activo útil y relevante. Algunos sintieron una falta de apoyo
terapéutico, y una mayor personalización de la orientación fue una sugerencia frecuente
para mejorar la adaptación individual. La eficacia de la IMI se percibió con mayor frecuencia
en sus efectos sobre la mejora del afrontamiento del trauma y los síntomas.
Discusión: El estudio identificó temas clave para la viabilidad de una IMI centrada en el trauma
para jóvenes, mostrando una aceptación general de su diseño, estructura y tecnología. Aunque
el procesamiento del trauma en las IMI plantea desafíos similares a los de la terapia presencial,
éstos pueden abordarse aclarando la justificación de la terapia, haciendo del procesamiento
del trauma un importante factor activo. Se necesita más investigación para mejorar la
individualización y la intensidad del apoyo terapéutico.
Abbreviations: APOI: Attitudes Towards Psychological Online Interventions Questionnaire;
CATS-2: Child and Adolescent Trauma Screen for DSM-5; COREQ: Consolidated criteria for
reporting qualitative research criteria; CSQ-I: Client Satisfaction Questionnaire in its version
adapted for Internet interventions (CSQ-I); IMI: Internet-and mobile-based intervention;
i-CBT: Internet-based cognitive behavioural therapy; i-tf-CBT: Trauma-focused internet-
based cognitive behavioural therapy; PTE-checklist: 15-item screen for exposure to
potentially traumatic events of the CATS-2; PTSD: Post-traumatic stress disorder; PTSS: Post-
traumatic stress symptoms; RCT: Randomised controlled trial
1. Theoretical background
In adults, internet-delivered cognitive behavioural
therapy (i-CBT) has been shown to eectively reduce
symptoms of post-traumatic stress disorder (PTSD;
Kuester et al., 2016; Lewis et al., 2019; Siddaway et al.,
2022), with preliminary evidence suggesting that
trauma-focused i-CBT (i-tf-CBT) can be superior to
non-trauma-focused interventions (Ehlers et al., 2023).
I-CBT for PTSD is a self-administered internet-based
intervention with written or electronic content based
on trauma-focused cognitive behavioural therapy.
When working through the online material, individuals
are supported by a therapist via chat, e-mail, telephone
call or in face-to-face sessions. However, research on i-
CBT for youth with post-traumatic stress symptoms
(PTSS) is scarce, with only six studies evaluating inter-
net-based interventions for youth exposed to traumatic
events (Schulte, Harrer, et al., 2024). Notably, none of
these studies evaluated a trauma-focused intervention,
despite trauma-focused psychotherapy being rec-
ommended as first-line treatment for children and ado-
lescents (ISTSS Guidelines Committee, 2019; Phelps
et al., 2022; Rosner, Gutermann, et al., 2020).
To address this research gap, a proof-of-concept non-
randomised feasibility study on a trauma-focused Inter-
net- and mobile-based intervention (IMI) with therapist
guidance was conducted on 32 youth with clinically sig-
nificant PTSS (Schulte, Sachser, et al., 2024). Results of its
preliminary ecacy suggested that the IMI can signifi-
cantly reduce PTSS and symptoms of depression, as
well as improve health-related quality of life at post-treat-
ment and follow-up compared to baseline, with moderate
to large eect sizes (d = 0.47–0.88). Additionally, the IMI
was found to be useful and understandable, with one-
third of the sample showing reliable within-person
improvement in PTSS from pre- to post-treatment. How-
ever, only one-third of participants completed the core
sessions of the IMI with approximately one-third stop-
ping before or within the trauma processing phase of
treatment (Schulte, Sachser, et al., 2024). To improve
the intervention and understand inuential factors on
adherence and ecacy, deeper insights into participants’
perceptions and engagement with IMIs are needed.
Incorporating theoretical models in qualitative con-
tent analysis is beneficial as they provide structured
theoretical frameworks that guide the interpretation
of complex data. These models help identify and organ-
ise key themes, ensuring that the analysis captures the
dierent dimensions of participants’ experiences. The
acceptability model for healthcare interventions
(Sekhon et al., 2017) provides a thorough framework
for understanding how people evaluate healthcare
interventions. It considers both anticipated and actual
cognitive and emotional responses to the interventions.
Besides, it includes aspects like coherence of the inter-
vention, perceived burden, and perceived eect. More-
over, the Eciency Model of Support focus on the role
of human support within IMIs, particularly how the
combination of self-guided engagement and human
guidance can impact the intervention’s ecacy and
suitability for individual needs (Schueller et al., 2017).
Little work has been done to understand how youth
experience trauma-focused interventions (Salloum,
2019). While one systematic review identified
2 C. SCHULTE ET AL.
qualitative studies evaluating youth and caregivers’
perspectives of tf-CBT (Neelakantan et al., 2019),
only one of these studies specifically focused on
youths’ experiences (Dittmann & Jensen, 2014). This
study found that youth aged 11–17 years initially
experienced anxiety about discussing their trauma
with an unknown person but ultimately found tf-
CBT and trauma processing beneficial, particularly
due to the therapist’s characteristics, such as transpar-
ency and empathy (Dittmann & Jensen, 2014).
Additionally, in a recent qualitative study on experi-
ences of tf-CBT for transitional-aged youth, partici-
pants reported therapist authenticity, autonomy and
control during therapy, and a sense of personal
responsibility in their recovery as important aspects
of the treatment (Eastwood et al., 2021). In adults
with mild to moderate PTSD, i-tf-CBT has been eval-
uated for acceptability using a mixed methods
approach. Although quantitative measures revealed
high acceptance and satisfaction with i-tf-CBT, the
qualitative insights highlighted the importance of per-
sonalisation based on participants’ individual prefer-
ences, symptom presentation, and treatment
expectations (Simon et al., 2023). However, in youth
with PTSS, eCoaching and intervention factors have
not yet been explored. Capturing and incorporating
insights gained from qualitative data into interven-
tions can improve their quality by tailoring them to
individual needs and preferences, thus increasing the
individual fit (Eastwood et al., 2021; Midgley et al.,
2014). Implementing these recommendations might,
in turn, mitigate dropout rates and enhance the
ecacy of treatments (Plaistow et al., 2014). There-
fore, this study aimed to explore youth’s experiences
participating in a therapist-guided trauma-focused
IMI and its evaluation study, focusing on acceptability,
satisfaction, and individual fit, particularly in relation
to adherence and perceived eect.
2. Methods
This qualitative study was part of a one-arm proof-of-
concept feasibility study evaluating a trauma-focused
IMI with therapist guidance for youth aged 15–21
years with clinically significant PTSS (Schulte et al.,
2022). The study was approved by the ethics commit-
tee of the German Psychological Society (DGPs, the
Society, EbertDavidDaniel2020-09-16-VA) and regis-
tered in the German clinical trial register
(DRKS00023341). The study was funded by the Fed-
eral Ministry of Education and Research (BMBF,
grant number 01KR1804D), as part of the collabora-
tive project BestForCan, which aims at disseminating
trauma-focused cognitive behavioural therapy devel-
oped by Cohen and colleagues (2009) for children,
adolescents, and young adults after child abuse and
neglect (Rosner, Barke, et al., 2020). This qualitative
study follows the consolidated criteria for reporting
qualitative research criteria (COREQ, Tong et al.,
2007, Appendix, eTable 1). Additional information
on the feasibility study can be accessed via the study
protocol and feasibility outcome papers (Schulte
et al., 2022; Schulte, Sachser, et al., 2024).
2.1. Eligibility criteria and procedure
Participants (n = 32) of the feasibility study were
recruited between July 2021 and January 2023 via
online (e.g. social media) and oine (e.g. counselling
services, youth clinics) recruitment channels. Partici-
pants were aged between 15 and 21 years and experi-
enced clinically relevant PTSS (measured with the
Child and Adolescent Trauma Screen for DSM-5;
CATS-2 ≥ 21; Sachser et al., 2022). Participants were
required to live in secure living conditions, as stipu-
lated by current treatment guidelines for PTSD in chil-
dren and adolescents (Rosner, Gutermann, et al.,
2020). In accordance with these guidelines, any exist-
ing risks to the child or adolescent must be thoroughly
assessed at the start of treatment. Where necessary,
immediate measures should be implemented to ensure
the child’s safety and support their well-being. They
provided written informed consent, with minors giv-
ing assent and requiring consent from caregivers or
the legal guardian.
All participants completed a baseline self-rated
online assessment (T1) prior to gaining access to the
IMI.. Eight weeks after accessing the IMI or upon
completing the eighth session of the IMI, all partici-
pants were invited to a self-rated online and a clini-
cian-rated telephone post-assessment (T3). The
qualitative interview was scheduled after the com-
pletion of the ninth session or 12 weeks following
initial IMI access. Only participants who had started
completing the online sessions, and had not with-
drawn their study consent were invited to participate
in the qualitative interview. Between January 2022
and May 2023, 28 youth out of 32 eligible participants
(87%) were invited to the qualitative interview. Four
participants were not invited as they did not start
the online sessions. Invited participants received up
to three email reminders and one phone reminder.
Out of 28 participants contacted, 19 scheduled an
appointment and took part in the interviews (n = 19/
32, 59%). Two participants had to be excluded due
to technical problems with transcription, resulting in
a final sample of 17 interviews.
2.2. Trauma-focused internet- and mobile-
based intervention
The content of the trauma-focused IMI was based
on face-to-face tf-CBT involving common com-
ponents of evidence-based manualized PTSD
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY 3
treatments: psychoeducation, emotion regulation and
coping, imaginal exposure, and cognitive processing
(Dorsey et al., 2011; Schnyder et al., 2015). The nine
sessions, consisting of eight core sessions and one
booster session scheduled four weeks after completion
of the core sessions, were modular in structure and
thematically divided into three units: (1) safety and
coping skills (sessions 1–3) involving psychoeduca-
tion, stabilisation, and emotion regulation techniques;
(2) trauma processing (sessions 4–6), which was con-
ducted through writing a trauma narrative; and (3)
consolidation and integration of the traumatic event
(sessions 7–9), including cognitive techniques, relapse
prevention, and the booster session to foster learned
skills and redefinition of goals. Participants were
encouraged to complete the first to eighth sessions
weekly and the ninth session after a four-week
pause, spanning a total of 12 weeks.
The sessions had an expected duration of 30–60
min each and were accessible via laptop or computer
on a web browser of an eHealth platform. Each session
comprised text, video, and audio content, interactive
components, download material, and three fictional
case descriptions. In addition, a smartphone app was
available to plan behavioural activation activities and
reect on the transfer and usefulness of exercises per-
formed in daily life. The online sessions were concep-
tualised as a self-help intervention guided by an
eCoach. The eCoach, a psychotherapist in training
with a master’s degree in psychology, provided semi-
standardised text-based feedback on completed ses-
sions. Participants received the written feedback in
asynchronous form after completing an online-ses-
sion. While certain aspects of the feedback followed
a standardised format, the eCoach customised aspects
such as addressing specific symptoms or the nature of
the trauma. The primary aim of the feedback was to
support and motivate participants while fostering
adherence to the intervention. Additionally, licensed
child and adolescent therapists were available upon
request to provide consultation sessions to partici-
pants via telephone. For the eCoaches, supervision
was oered by a licensed child and adolescent thera-
pist. The study protocol provides detailed information
on the IMI (Schulte et al., 2022).
2.3. Qualitative data collection
The semi-structured interview guide contained 38
open questions organised into eight topics: motivation
and expectations (4 questions); active factors, ecacy,
and individual fit (8 questions); treatment adherence
and everyday use of the IMI (6 questions); acceptance
of the IMI content (5 questions); design of the IMI (3
questions); human guidance through the IMI and the
study (3 questions); concluding evaluation of partici-
pating in the study and IMI (4 questions); and further
comments including optimisation suggestions (5
questions). In addition, memo questions (e.g. ‘What
were your reasons for signing up?’ to clarify key
aspects and ‘hang-on’ questions (e.g. ‘What else can
you think of?’, ‘What was it like for you?’, ‘Can you
describe it to me in more detail?’) were given to ensure
detailed answers and to clarify comprehension
diculties. Participants were given ample opportunity
to elaborate on their responses, with the interviewer
proceeding to the next question only after participants
had fully conveyed their thoughts or indicated they
had nothing further to add. Example questions for
each topic are shown in Table 1. The complete list of
questions can be found in the Appendix (eTable 2).
Table 1. Example questions on the eight topics from the
interview guide for the qualitative interviews.
Topic Example Question(s)
Motivation and expectations What motivated you to seek help at the
time you signed up for the study?
What expectations did you have of the
online training before you started?
Active factors, efficacy, and
individual fit
To what extent was the online training
helpful for you regarding your
problems?
To what extent did you feel that the
online training ‘involved everything’
you needed for your problems?
What do you think you have actively
contributed to changing your
problems?
Working on the IMI content How did you manage to make time for
the online sessions in your everyday
life?
What else would you have needed to
make more time for training in your
everyday life?
Acceptance of IMI content To what extent did you generally have the
impression that the units build on each
other and fit together well in terms of
content?
What moments during your training did
you feel under-challenged or
overwhelmed?
IMI design What did you like and dislike about the
design of the online training?
To what extent did you have technical
problems either with the online training
or with the realisation of the exercises
(for everyday life)?
Human guidance in IMI and
study context
How did you get on with your eCoach,
overall?
How would you describe your
relationship with your eCoach?
To what extent did you feel that your
problems were seen and taken seriously
during the training and the study?
Evaluation of study and IMI
participation
To what extent was it worthwhile for you
to take part in the training?
Based on your experience with online
training, what should other young
people bring with them so they can
complete the training well?
Further comments and
optimisation suggestions
To what extent do you have any
suggestions or comments that could
improve the online training and the
study?
What are your ideas on how we can reach
young people and raise awareness of
the study and the online training?
Note: IMI = Internet- and mobile-based intervention.
4 C. SCHULTE ET AL.
The semi-structured interview guide was partly
based on expert considerations of relevant aspects of
assessing the overall experiences of youth with the
trauma-focused IMI, and partly based on theoretical
models of the acceptability of healthcare interventions
(Sekhon et al., 2017) and the integration of human
support (Eciency Model of Support; Schueller
et al., 2017). The model for the acceptability of health-
care interventions was chosen because it oers a com-
prehensive framework that captures how individuals
perceive the appropriateness of these interventions,
considering their expected and actual cognitive and
emotional responses, such as coherence, perceived
burden, and eectiveness (Sekhon et al., 2017). The
Eciency Model of Support was chosen as it empha-
sises human support in IMIs and how the interaction
between self-directed participation and human gui-
dance might inuence the ecacy of the intervention
(e.g. in terms of individual fit; Schueller et al., 2017).
The interviews were conducted between January
2022 and May 2023 by a female researcher (CS). CS
conducted and analyzed the interviews as part of her
doctoral studies and was in training to become a
licensed therapist. She had no prior relationship with
the participants but was involved in the development
of IMI and filmed videos for the IMI sessions in
which her voice was heard. Participants were informed
at the beginning of the qualitative interview that CS
was involved in the development of IMI and was inter-
ested in their general experiences with IMI. The inter-
views were conducted via phone and audio-recorded
via PhonerLite (Sommerfeld, 2019). The average dur-
ation of an interview was 48 minutes (SD = 13, range:
28–70). The audio recordings were transcribed verba-
tim and thereby anonymized using a transcription
guide and the software tool MAXQDA (VERBI Soft-
ware, 2021).
2.4. Quantitative data collection
We report quantitative data from T1 and T3 assess-
ments to compare interviewees with non-interviewed
feasibility study participants based on several charac-
teristics: sample characteristics include sociodemo-
graphic data (e.g. age, gender, residence, education)
and self-reported data on health (e.g. prior treatment,
physical disease, mental disorder). Satisfaction and
acceptability were assessed with the Client Satisfaction
Questionnaire in its version adapted for Internet inter-
ventions (CSQ-I; eight items, score range: 8–32;
α = .95; scores > 23 indicate high satisfaction; Boß
et al., 2016) at T3, and the Attitudes towards Psycho-
logical Online Interventions Questionnaire (APOI; 16
items; score range: 16–80; higher scores on the total
scale indicate more positive attitudes; Schröder et al.,
2015) at T1 and T3. Intervention adherence was
assessed by the number of completed online sessions
and objective user data (e.g. number of logins, number
of messages). Symptom severity in terms of PTSS was
assessed with the CATS-2 DSM-5 scale (20 items;
score range: 0–60, α = .81; Sachser et al., 2022) at
each time point (T1, T3) and the 15-item screen for
exposure of potentially traumatic events of the CATS
was used to assess traumatic events at screening
(PTE-checklist). Diagnosis of PTSD was assessed
with the Clinician-Administered PTSD Scale for
DSM-5 Child and Adolescent Version (CAPS-CA-5)
by licensed psychotherapists (20-item DSM-5 scale;
score range: 0–80; α = .76; Pynoos et al., 2015) at T1
and T3. All quantitative data is reported for study
completers only, meaning those who provided data
in the online – and telephone assessments at T3. A
detailed description of assessments is reported in the
study protocol (Schulte et al., 2022) and a detailed
sample description can be found elsewhere (Schulte,
Sachser, et al., 2024).
2.5. Data analysis
Qualitative content analysis with a deductive-induc-
tive approach was carried out following the established
processes in qualitative research (Mayring, 2015) to
synthesise interview data and determine elements rel-
evant to the study topic. A second rater, JW, was
involved in the qualitative data evaluation to ensure
the reliability of the findings. JW was an independent
research assistant with no prior relationship to the
participants (eFigure 1 in the Appendix depicts the
complete procedure, including data collection and
analysis): (1) Main categories based on the topics of
the interview guide were derived (deductive
approach). (2) Initial coding rules were developed
that define one sentence as the smallest coding unit
and a complete statement as a context entity.
(3) Two independent coders (CS, JW) worked through
the transcribed material simultaneously and derived
subcategories and codes (inductive approach) with
the goal of code saturation. Subcategories were reor-
ganised, codes were added or adapted, and coding
rules were redefined and completed. Regular consen-
sus meetings (JW, CS, AZ) were held to discuss the
structure of the code system, the code definitions,
and example statements. Preliminary coding systems
were tested and revised according to the feedback.
In this process, the gradual inclusion of the raw
material resulted in including 100% of the material
(n = 17). (4) The preliminary code system and coding
rules were tested for comprehensibility and complete-
ness in one of the transcribed interviews (2%, n = 1).
(5) Final adaptations of the code system and coding
rules were performed (CS, JW). (6) Two independent
coders carried out the final coding on 100% (n = 17) of
the transcribed material (JW, CS). (7) Cohen’s Kappa
was determined in terms of the presence of a code in
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY 5
the document, the frequency of a code in the docu-
ment, and the overlap of codes (at least 90%) of each
coded segment (Mayring, 2015). Values of κ < .41
were rated as low, κ = 0.41–0.60 as moderate, κ =
0.61–0.80 as substantial, and values κ ≥ 0.81 were
rated as (almost) perfect agreement (Brennan & Predi-
ger, 1981; Landis & Koch, 1977). Determination of the
coded material resulted in a 96% overlap in terms of
presence of a code in the document, 91% in terms of
frequency of a code in the document, and 76% in
terms of code overlap (at least 90%) of each coded seg-
ment with Kappa of κ = .76. MAXQDA (VERBI Soft-
ware, 2021) was used for qualitative data analysis, and
SPSS 29 (IBM Corp., 2017) was used for quantitative
data analysis.
3. Results
3.1. Participant characteristics
Out of the 28 participants contacted, 19 scheduled an
appointment and participated in the interviews (n =
19/32, 59%), though two had to be excluded due to
technical issues with the audio recordings. Interview
participants were on average 19 years old (SD = 1.8)
and predominantly female (77%, n = 13/17). Their
baseline level of PTSS was high (M = 30.9, SD = 8.8)
and the majority fulfilled diagnostic criteria for
PTSD according to CAPS-CA-5 (76%, n = 11/17).
Interview participants were representative of non-
interviewed participants on sample characteristics
except for symptom burden, which was slightly higher
in the non-interviewed sample (Table 2). Regarding
the type of trauma experienced, interviewed partici-
pants reported having experienced sexualised violence
(71%, n = 12/17), bullying (35%, n = 6/12), family vio-
lence (29%, n = 5/17), other stressful or scary events
(23%, n = 4/17), witnessing violence in the family
(12%, n = 2/17), sudden death of a loved person
(12%, n = 2/17), or a medical event (12%, n = 2/17).
A comparison of the traumatic events reported by
interviewed and non-interviewed participants can be
found in the Appendix (eTable 3).
3.2. Comparison between interviewed and non-
interviewed participants on quantitative
findings
3.2.1. Satisfaction and acceptability
Satisfaction among interviewed participants was high
at T3 (M = 27.5, SD = 4.1, range: 16–32, n = 15/17)
and greater than the satisfaction score of non-inter-
viewed participants, which was just below the
threshold for high satisfaction (M = 22.7, SD = 7.8,
range: 8–32, n = 7/15). The results of the APOI can
be found in the Appendix (eTable 4).
3.2.2. Intervention usage
More than half of the interviewed participants had
completed the IMI’s eight core sessions (n = 10/17,
58%) whereas none of the non-interviewed partici-
pants completed all eight core sessions. Overall, the
intervention usage of interviewed participants was
higher than those of non-interviewed participants
(see details in the Appendix, eTable 5).
3.2.3. Symptom severity
PTSS decreased both by 9 points from T1 to T3 in the
group of interviewed participants (T1: M = 30.9, SD =
8.8, n = 17/17; T3: M = 21.5, SD = 9, n = 15/17) and the
group of non-interviewed participants (T1: M = 32.5,
SD = 6.4, n = 15/15; T3: M = 24, SD = 14, n = 7/15).
CAPS severity decreased both by 10 points in the
group of interviewed participants (T1: M = 31.8, SD
= 8.9, n = 17/17; T3: M = 21.1, SD = 11.7, n = 16/17)
and non-interviewed participants (T1: M = 31.1, SD
= 6.8, n = 15/15; T3: M = 21.2, SD = 13.3, n = 6/15).
3.4. Qualitative findings
In total, 20 themes were identified and organised
under nine dimensions: participation motivation and
expectations; recruitment process; treatment adher-
ence and everyday use of therapeutic exercises; trauma
processing; non-trauma processing intervention
Table 2. Sociodemographic data at baseline assessment from
interviewed and non-interviewed participants.
Interviewed
participants (n =
17)
Non-interviewed
participants (n = 15)
Age M (SD) 19 (1.8) 19 (1.7)
Gender n (%)
Female 13 (77) 15 (100)
Male 3 (18) 0 (0)
Diverse 1 (6) 0 (0)
Self-reported mental disorder(s) n (%)
Lifetime diagnosis of
any mental disorder
10 (59) 8 (53)
Depression 8 (47) 5 (33)
PTSD 3 (18) 5 (33)
Borderline personality
disorder
2 (12) 1 (7)
Anxiety disorder 2 (12) 1 (7)
Attention deficit
hyperactivity disorder
1 (6) 0 (0)
Bulimia nervosa 1 (6) 0 (0)
Personality disorder (not
defined)
1 (6) 0 (0)
Alcohol consumption
disorder
1 (6) 0 (0)
Previous treatment (for
any mental disorder) n
(%)
8 (47) 8 (53)
Physical disease n (%) 1 (6) 5 (33)
PTSS (CATS), M (SD) 30.9 (8.8) 32.5 (6.4)
PTSD diagnosis (CAPS-CA-
5, clinician-rated), n (%)
11 (76%) 13 (86%)
Note: CAPS-CA-5 = Clinician-Administered PTSD Scale for DSM-5 - Child
and Adolescent Version (Pynoos et al., 2015). M = mean. PTSD = post-
traumatic stress disorder. PTSS = post-traumatic stress symptoms
measured with CATS (Child and Adolescent Trauma Screen; Sachser
et al., 2022). SD = standard deviation. T1 = Baseline, self-rated online
assessment before IMI access.
6 C. SCHULTE ET AL.
components; technology, structure, and design of the
IMI; human support in IMI and the study; individual
fit of IMI and study parameters; and active factors and
ecacy.
For each theme, the most frequently reported codes
are presented below and illustrated with a quote.
Additionally, opposing codes or diverse cases were
included to reect the heterogeneity of the findings
and to address less commonly reported experiences.
Quotes are attached with participant tags (p1-p17) to
demonstrate representation across the sample. The
following terms are used to indicate the number of
participants expressing a particular theme, experience,
or idea: a few (3–5), some (6–8), and many (≥ 8; San-
delowski, 2001). An overview of all identified themes
with descriptions and quotes for illustration can be
found in the Appendix (eTable 5).
3.4.1. Participation motivation and expectations
The dimension ‘participation motivation and expec-
tations’ entailed various expectations for the IMI regard-
ing its content, structure, and ecacy, as well as the
motives for participating in an IMI study, which also
encompassed the barriers to other help-oers. Barriers
to on-site psychotherapy, such as limited availability
and long waiting times, motivated many to participate
in the study (n = 14; 82%), with one participant expres-
sing the high eort required to get into therapy.
It’s so hard to get a spot in therapy. I think people are
also somewhat put o by all this bureaucratic stu.
You have to contact a thousand dierent places and
make a lot of phone calls before you might get some-
thing. (p2)
An IMI therefore seemed ‘more practical, because you
can do it from home’ (p4), meaning time- and place-
independent use was another motivator for many (n
= 10; 59%).
The expectations towards the IMI were few, with
most participants having an exploratory attitude
towards the IMI and the study with no concrete idea
of its structure and content but being willing to try
it out (n = 12, 71%). However, many expected to
acquire strategies to cope with the trauma and related
symptoms (n = 10, 59%). One example quote illustrat-
ing both themes is as follows:
I didn’t have super high expectations, to be honest. I
mean, I thought that it would help me with strategies
and stu, but I didn’t know how it worked exactly
because I’d never had any experience with it … then
I thought, okay, I’ll just try it out and see if it works
or not. (p17)
Two participants expected to ‘start to kind of process
everything and start to deal with it’ (p2) or to ‘kind of
deal with my traumas’ (p5), indicating that the expec-
tation of trauma processing within the IMI (n = 2,
12%) also remained rather vague.
3.4.2. Recruitment process
The dimension ‘recruitment process’ comprised var-
ious recruitment channels through which participants
became aware of the study or which were indicated
as relevant for reaching out to youth with PTSS, as
well as the characteristics of the study registration
and inclusion process. Many participants found that
recruitment via media, especially through advertising
on social media platforms such as Instagram, would
be most eective in reaching youth with PTSS (n =
13, 76%). Additionally, many youth indicated pro-
fessionals as eective referrers (n = 8, 47%). A quote
illustrating both themes is as follows:
Maybe write to each therapy center to see if they can
put out yers? For those who have the problem of not
being able to speak to someone in person. So just that
at every therapy and counseling center, that they
briey tell you about it or that you maybe post it on
Instagram or write to Instagram, to see if they can
advertise it. (p8)
The majority of participants reported experiencing a
certain amount of timing, structural or psychological
strain during the study registration process, but over-
all, they still found it acceptable in terms of the eort
required (n = 16; 94%). One quote illustrates this per-
ception as follows:
Generally not that complicated. The phone call was
(…) I think over an hour. I haven’t had a phone call
that long for a while (laughs). But that’s not a problem
at all. (p1)
Two participants had diculties indicating an emer-
gency contact during the registration process (n = 2;
12%), with one of them perceiving it as ‘the hardest
part to find someone who could be an emergency con-
tact’ and ‘talking to people about it’ (p9). Conversely,
two participants saw advantages in the emergency plan
and contact, appreciating the involvement of another
person (n = 2; 12%) and perceived that ‘it’s generally
a good idea to have a second person involved, some-
one to talk to in case the sta get the impression
that something worse might be going on (…)’ (p15).
3.4.3. Treatment adherence and everyday
realisation of therapeutic exercises
The dimension ‘treatment adherence and everyday use
of therapeutic exercises’ entailed both the supporting
adherence and everyday-transfer factors and the hin-
dering adherence and everyday-transfer factors ident-
ified by youth to completing the online sessions of
the IMI and implementing the therapeutic exercises
in their everyday life. Most of the supporting factors
for treatment adherence and everyday use were intrin-
sic factors, such as characteristics, attitudes, or partici-
pant beliefs. Half of the participants stated that self-
organisation – meaning the sense of self-determined
and exible planning of when they planned to conduct
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY 7
the sessions and the hours they wanted to spend on the
session – was a supporting factor for carrying out and
implementing the IMI and therapeutic exercises (n =
9, 53%). One tag summarising this theme is as follows:
I always write a plan for the week at the beginning of
the week, so I immediately check which day I have the
most time, to make sure that I don’t start the training
when I’m already stressed or something. In other
words, I wrote it down in my schedule and it always
worked out. (p1)
Another supporting factor of treatment adherence and
everyday use of therapeutic exercises was the belief in
the benefits of the IMI, either due to experiencing its
ecacy first-hand and ‘just [noticing] how good it is
for me’ (p11), or because of the feeling of doing some-
thing good for one’s future (n = 3, 18%). However,
some others (n = 3, 18%) expressed experiencing a
lack of ecacy as a hindering factor in treatment
adherence and everyday use. For example, one partici-
pant clearly stated: ‘I mean, I haven’t gone any further
with it at all. The reason being that I don’t feel that it
has helped me’ (p2). The most common hindering fac-
tors mentioned by a few participants were external
barriers like experiencing external stressors related to
work or leisure activities (n = 6, 35%), lack of time
(n = 5, 29%), or technical restrictions such as problems
with the internet connection (n = 5, 29%).
3.4.4. Trauma processing
The ‘trauma processing’ dimension covered the chal-
lenges that youth anticipated or experienced during
trauma confrontation or its practical usage, as well
as the reasons for an overall positive evaluation of
the trauma processing. A total of 10 participants
(59%) expressed at least one challenge related to
trauma processing. Most frequently, participants
described experiencing or fearing an increase in nega-
tive symptoms due to trauma processing (n = 7, 41%),
as one participant stated:
What I didn’t want to do at the beginning was writing
the blog article, because I had the feeling that I would
end up falling further into it and that it would really
disturb me. (p7)
A few experienced a lack of therapeutic support when
imagining or going through the trauma processing
as they felt ‘just kind of alone with it all’ after ‘turning
o the laptop’ and found that ‘there was probably
something missing’ (p2). From these ten participants
expressing at least one challenge, six participants
(60%) still came to an overall positive evaluation of
the trauma processing. Furthermore, seven partici-
pants evaluated trauma processing as positive without
expressing any challenges, resulting in a total of 13
participants (n = 13/17, 76%) with an overall positive
evaluation of trauma processing. Most often, this posi-
tive evaluation was the result of participants reframing
challenges in light of the fact that processing the
trauma was helpful or even necessary for improve-
ment, which could be summarised as trauma proces-
sing is challenging but helpful (n = 9, 53%). One
quote illustrates this perception as follows:
I found it very dicult to write the trauma narrative.
But in the end, it was good that I really dealt with it,
because it allowed me to come to some kind of peace
with it. The fact that I wrote it down. (p8)
3.4.5. Non-trauma processing intervention
components
The dimension ‘non-trauma processing intervention
components’ included youths’ ratings of non-
trauma-processing components as either helpful or
unhelpful components in processing the sessions or
implementing them in daily life. Overall, there were
more components found to be helpful than unhelpful.
Almost all participants found the aect regulation
techniques, including breathing, self-soothing, and
distress tolerance techniques, helpful when complet-
ing the sessions or using them in everyday life (n =
16, 94%). For example, one participant stated that it
helped me in everyday life in particular because when
I needed to calm down or when I was feeling bad, I
would try smelling these essential oils or something,
for example. After all, I always had them with me in
my bag. (p10)
In contrast, the imagination-based emotion regulation
techniques were perceived as unhelpful by one-third
of participants (n = 5, 29%), stating that ‘imagine
that the thoughts are oating away on the clouds’
was ‘definitely not helpful’, because ‘maybe I just
couldn’t feel my way into it or somehow can’t take it
seriously enough’ (p3) and found the idea of putting
feelings on a cloud ‘strange’. The remaining interven-
tion components, such as aect regulation techniques,
motivational goal setting, or the fictional case descrip-
tions, were rated as unhelpful by only one or two par-
ticipants but were rated as helpful by several others.
3.4.6. Technology, structure, and design of the
IMI
The dimension ‘technology, structure, and design of
the IMI’ entailed both positive and negative aspects
related to these elements of the IMI. Overall, there
were more positive aspects of the IMI emphasised
than negative aspects regarding technology, structure,
and design of the IMI. Almost all participants high-
lighted the clearly structured content as a positive
aspect of the IMI (n = 16, 94%).
So it was definitely well structured, the content was
consistent, the sessions built upon each other very
nicely and there was always a short reminder at the
beginning about what happened in the previous ses-
sion. (p7)
8 C. SCHULTE ET AL.
Additionally, the appealing design, including illus-
trations that ‘felt sort of calm’ (p12) and an intuitive
layout that facilitated usability, was also highlighted
as a positive aspect, as was the use of metaphors
(each n = 16, 94%). However, two youth perceived
the metaphors as inappropriate, finding them too
simple to help explain their burden (n = 2, 12%).
The most frequently mentioned negative aspect was
technical usage problems in the sense of programming
errors, which meant that ‘several things, such as text
labels, (…) just weren’t displayed or only the code
was shown’ (p7) or that there were problems with
the app functions, such as journaling or planning posi-
tive activities (n = 10, 59%).
Furthermore, some participants found the content
to be overloaded (n = 4, 59%) and some IMI com-
ponents to be poorly integrated or structured (e.g.
the app activity planner; n = 4, 59%), leading to con-
fusion and dissatisfaction with the IMI: ‘And just in
general, the activity planner was a bit confusing,
dicult to find once I’d lost it and barely explained
at all or integrated into the training itself. I thought
that was a little disappointing’ (p7).
3.4.7. Human support in IMI and the study
The dimension ‘human support in IMI and the
study’ included both the positive aspects of human
support, such as eCoaching and contact with
licensed psychological therapists during diagnostic
interviews or telephone consultation sessions, as
well as interactions with the study team. It also
addressed the negative aspects related to these inter-
actions. Most participants appreciated the beneficial
interpersonal factors and communication throughout
the IMI and the study, such as empathy, trust,
respect, and feeling as though they were taken
seriously (n = 16, 94%). One participant summarised
their experience with the eCoach and the study
team as follows:
Respectful. Just very understanding. Definitely noth-
ing negative. Yeah, they just value you. I think I
could have written anything, any problem, and she
[the eCoach] would have always listened and would
have always been able and willing to help me. (p11)
However, some participants reported that they did not
perceive the contact with the eCoaches as a real, trust-
ing relationship. One participant stated, ‘I don’t feel
that I really built up a mutual trust or anything’
(p2), which was framed in terms of a lack of a thera-
peutic relationship within the intervention (n = 6,
35%). Some also experienced deficits in interpersonal
factors and communication, as they ‘didn’t really feel
heard’ (p7) (n = 4, 24%). This was especially relevant
for one of these four participants, who reported feeling
disappointed by the fact that the eCoach changed
during the study participation.
3.4.8. Individual fit of IMI and study parameters
The dimension ‘individual fit of IMI and study par-
ameters’ included perceived requirements for the indi-
vidual fit of the IMI that youth considered necessary
for good feasibility based on their experiences with
the IMI and the study. It also covered suitable aspects
and unsuitable aspects of the IMI and study concern-
ing their needs, as well as suggestions for optimising
the individual fit. Acceptance and willingness to
change, including accepting that the trauma has hap-
pened, the willingness to deal with the traumatic
memories, and the necessity to be honest with oneself,
were seen by many participants as a prerequisite for
participation in the IMI and the study (n = 10, 59%).
One participant expressed this condition in the follow-
ing words:
The courage to deal with it – with what you’ve been
through, with the trauma, and yeah, you have to do
that in the lessons, so it would definitely be good
for you to more or less feel ready to do that. (p4)
Most participants found at least some, and in certain
cases all, of the IMI components to be suitable and tai-
lored for their needs or that they were building upon
their previous knowledge, leading to satisfaction with
the therapeutic content (n = 14, 82%). However, more
than one-third of participants expressed unsuitability
of the IMI and study parameters due to a lack of per-
sonal contact with eCoaches or psychotherapists,
instead expressing a need for real-person interactions
(n = 6, 35%). One participant very clearly stated that
she was ‘just more suited for something in person.
For me, any online therapy – no matter how good
or bad it is – just can’t replace that, I think’ (p2). Con-
sequently, more than half of the participants suggested
more personalised guidance, with less manualized
eCoach feedback ‘to be reminded again that it’s not
just some kind of chatbot behind the scenes’ (p6),
especially during the trauma-confrontation phase, or
live video sessions with eCoaches or psychotherapists
(n = 9, 53%). However, one person would have pre-
ferred less personal contact within the IMI, meaning
fewer telephone contacts with the psychotherapists
for the diagnostic assessments (n = 1, 6%).
Another frequently mentioned optimisation sug-
gestion was to have a broader choice (n = 6, 35%) in
the selection of intervention components or in the
selection of the order and timing of the sessions. For
example, one participant wished to have ‘a sort of
second alternative path or something’ (p15). Further,
some suggested to enhance the activation and inte-
gration of IMI content (n = 6, 35%), such as incorpor-
ating interactive videos or ‘a bit more and clearer
instructions’ (p2). Some suggested to simplify the
study registration process (n = 3, 18%), for example
by making use of online forms instead of emails or
generally using less emails, and one participant wished
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY 9
to have local tips for behavioural activation (n = 1,
6%). Overall, the optimisation suggestions dimension
was the one with the most themes identified and the
highest heterogeneity.
3.4.9. Active factors and ecacy
The dimension ‘active factors and ecacy’ encom-
passed the active factors perceived by youth that
potentially contributed to individual changes, as well
as the aspects in which they experienced the ecacy
of participating in the IMI or study. The majority of
participants indicated that processing and applying
the IMI content, in terms of actively engaging with
the session content, carrying out the therapeutic exer-
cises (e.g. relaxation techniques, trauma confronta-
tion), and integrating and applying the ‘things
learned’ into everyday life contributed to the perceived
changes and thus represented an active factor (n = 12,
71%). Approximately half of the participants (n = 8,
47%) stated that dealing with the trauma in the form
of ‘all that writing’ in the IMI sessions had ‘helped a
lot to sort and process everything’ (p3).
In terms of the perceived ecacy of the IMI, most
participants reported improved coping with trauma
and symptoms (n = 12, 71%), indicating that they
were more able to use coping strategies if symptoms
occurred or that they had come to a more helpful
appraisal of the trauma and its consequences. One
participant stated: ‘It’s not like ‘oh god, oh god, some-
thing was done to me and now I won’t be happy for
the rest of my life’, but it’s more like ‘yes, it happened,
my life goes on’ (p4). The improved coping was often
accompanied by an enhanced understanding of the dis-
order (n = 10, 59%), which enabled the participants to
better categorise and normalise symptoms and ‘be a
bit more objective and don’t immediately become
emotional and start spiralling. Just this sort of under-
standing of it’ (p1).
4. Discussion
This qualitative study is the first study to examine par-
ticipants’ perspectives on the feasibility of a trauma-
focused IMI using qualitative content analysis.
Youth who chose toparticipate in the interviews
were comparable in sociodemographic characteristics
and symptom severity to those who did not partici-
pate.. However, satisfaction and adherence to the
intervention was slightly higher in interviewed versus
non-interviewed participants. The satisfaction of
interviewed participants with the therapeutic content
and its everyday use were mirrored in the fact that
more positive than negative aspects of the design
were highlighted by participants. Moreover, helpful
IMI components were coded significantly more fre-
quently than unhelpful components, and a majority
expressed satisfaction with the IMI. Frequently
mentioned suggestions for optimisation related to
the type of guidance, the choice of exercises, and the
expansion of the app function.
Participants valued the exibility and accessibility
of the IMI, which addressed barriers to on-site
therapy. Recruitment via social media and pro-
fessionals was eective, and while the registration pro-
cess was manageable, some simplifications were
suggested. Youths approached the IMI with open
and exploratory expectations, hoping to gain strategies
for managing trauma and its symptoms. Adherence
was supported by organisational skills but hindered
by external stressors and limited time. Trauma proces-
sing was challenging due to symptom exacerbation
and avoidance but was ultimately seen as necessary
and eective by most participants. To optimise the
individual fit of therapeutic intervention components,
more exibility in the choice of techniques and
sequencing and scheduling of sessions was proposed.
The interpersonal contacts were often perceived posi-
tively, but some did not view their interactions with
the eCoach as constituting a true therapeutic relation-
ship. However, some participants reported that such a
therapeutic relationship would have been an impor-
tant supportive factor in trauma processing, or
would have been relevant to individual fit. Many
suggested that human guidance in the IMI should be
more personalised. Acceptance and willingness to
change were viewed as critical for success, and active
engagement improved coping with trauma and related
symptoms.
The unclear expectations towards a trauma-focused
IMI might partly reect the lack of research and avail-
able or known IMIs for youth with traumatic experi-
ences. However, it might also suggest a more general
lack of knowledge in youth regarding psychotherapy,
PTSD and related symptoms, and the fact that PTSD
is treatable. Such knowledge is relevant before or
when start treatment for PTSD to mitigate a rise in
treatment anxiety (Dittmann & Jensen, 2014), which
may otherwise lead to premature termination of the
intervention. Moreover, meta-analytic evidence
suggests that higher treatment expectancy serves as a
predictor for higher treatment adherence in IMI
studies (Beatty & Binnion, 2016). The reasons for par-
ticipating in the IMI expand the quantitative results of
the feasibility study, in which a preference for self-help
and perceived attractiveness of an IMI were indicated
as the most common reasons for participation, along
with overly long waiting times for on-site psychother-
apy (Schulte, Sachser, et al., 2024). Both qualitative
and quantitative results align with findings from pre-
vious qualitative studies evaluating barriers to mental
health care for trauma-exposed youth (Ellinghaus
et al., 2021) and youth in general (Pfeier & In-
Albon, 2022). Together, results highlight not only
the lack of available therapists but also individual
10 C. SCHULTE ET AL.
challenges with face-to-face therapy, such as not want-
ing to disclose one’s experiences to a therapist or fear-
ing or experiencing invalidating or negative reactions
from professionals.
The factors supporting and hindering treatment
adherence and the everyday use of therapeutic exer-
cises in everyday life in our study are in line with
those found in an IMI study on adult patients with
depression (Donkin & Glozier, 2012) and meta-ana-
lytic evidence of predictors of intervention adherence
in IMI studies (Beatty & Binnion, 2016). Donkin and
Glozier (2012) identified that intrinsic motivations,
such as perceived treatment benefits and a sense of
control, were crucial for engagement in the IMI,
while results of a meta-analysis suggested that
sucient time and personalised IMI content might
serve as predictors for higher adherence (Beatty &
Binnion, 2016). Similarly, our study highlighted self-
organisation and a wish for a more self-directed selec-
tion of exercises and session timing as relevant factors
for programme adherence. This suggests that having
the feeling of control might also be important for suc-
cessful engagement of therapeutic exercises in every-
day life among young people. Indeed, early research
has shown that taking into account youths’ need for
independence and autonomy might contribute to
increase satisfaction with therapy (Church, 1994),
and the need for control might be particularly pro-
nounced among trauma survivors, who often experi-
ence a sense of powerlessness during traumatic
events (Harvey, 2000; Skinner et al., 2019).
Many participants in the current study reported
experiencing challenges related to trauma processing,
such as increased negative symptoms or avoidance.
These results align with findings from face-to-face tf-
CBT, where terms like ‘dicult,’ ‘potentially distres-
sing,’ ‘emotionally upsetting,’ ‘painful,’ or ‘just feeling
scared about thinking about it’ are commonly used to
describe trauma processing (Dittmann & Jensen, 2014;
Eastwood et al., 2021). At the same time, the majority
of youth seemed to recognise the necessity of facing
and overcoming these challenges as essential for
recovery (Dittmann & Jensen, 2014; Eastwood et al.,
2021). Our results suggest that psychoeducation, nor-
malising reactions, and explaining the rationale for
trauma-focused intervention components, which
were all part of the IMI, might enhance understand-
ing, motivation for change, and ultimately adherence
to the IMI.
The type and intensity of guidance emerged as rel-
evant factors for IMI engagement in our sample, with
participants expressing a wish for frequent or more
personal contact. Meta-analytic research investigating
the role of guidance in IMIs for mental disorders like
depression and anxiety has found that guided IMIs
improve adherence rates compared to unguided
IMIs, especially in severely aected individuals
(Domhardt et al., 2019; Karyotaki et al., 2021; Musiat
et al., 2022; Zarski et al., 2016). Qualitative findings in
face-to-face tf-CBT highlight the importance of the
quality of the therapeutic relationship, including auth-
entic care, transparency, empathy, and professional-
ism (Dittmann & Jensen, 2014; Eastwood et al.,
2021). Given that providing extensive therapeutic gui-
dance in IMIs is costly, time-consuming, and poten-
tially aects scalability and IMI implementation, the
ability to build a therapeutic alliance under brief and
virtual conditions is important. Though an i-tf-CBT
study on adults showed that alliance was rated lower
at post-treatment compared to face-to-face CBT
(Simon et al., 2023), research into the quality of the
therapeutic relationship in IMI studies suggests that
high levels of working alliance can nonetheless be
achieved (Bur et al., 2022; Doukani et al., 2024). More-
over, one study on a transdiagnostic intervention for
students found no superiority of human guidance
over technological guidance, indicating that auto-
mated guidance might be a promising way to promote
treatment adherence and should be further evaluated
(Koelen et al., 2024). Overall, while many participants
desired more support, others preferred less contact or
none at all, suggesting that tailoring the intensity and
frequency of human guidance to individual patient
needs could be beneficial.
4.1. Limitations
Several limitations must be considered when inter-
preting the results. First, all interviewees began and
completed at least four sessions of the trauma-focused
IMI, meaning the findings may not adequately reect
the views of those who did not start or who terminated
prematurely; it is possible that the present findings
overestimate positive views of the IMI. However, indi-
viduals who terminated their participation in the IMI
prematurely were also invited to participate in the cur-
rent study, though they could not be reached despite
multiple attempts to contact them. Second, our deduc-
tive-inductive analysis did not achieve full saturation.
Interviewing more participants, which was not poss-
ible due to the small overall sample from the original
study, might have led to higher saturation. Third,
the interviews were conducted by a person involved
in the development and evaluation of the IMI, which
may have introduced bias in analyzing and interpret-
ing the results. To ensure the reliability of the findings,
a second-rater, who was not involved in the IMI’s
development and evaluation, also analyzed and inter-
preted participant responses. Additionally, partici-
pants were informed of the interviewer’s
involvement in IMI development prior to the inter-
views, which may have made them hesitant to give
critical feedback. Fourth, although the interviews
were scheduled immediately after intervention
EUROPEAN JOURNAL OF PSYCHOTRAUMATOLOGY 11
completion, some interviews were delayed, increasing
the likelihood of recall bias. In other cases, the inter-
views took place when the intervention was (not yet)
completed, thereby limiting the ability to speak
about experiences with the full content of the
intervention.
4.2. Future research
This qualitative interview study on a trauma-focused
IMI with therapist guidance for youth revealed
important considerations that require further investi-
gation and highlights factors that may help to
improve the feasibility of a digital trauma-focused
IMI in youth. To clarify intervention expectations,
reduce treatment-related anxieties, and foster inter-
vention adherence, future research could explore
acceptance-facilitating interventions (AFIs; e.g. Bau-
meister et al., 2014; Ebert et al., 2015) before IMI
use. AFIs may improve users’ attitudes by presenting
beneficial information in various formats (e.g. video,
paper brochure). For youth with PTSS, AFIs could
focus on providing information through a video
with a professional, as transparency, empathy, and
expertise have been shown to alleviate therapy con-
cerns in traumatised youth undergoing trauma treat-
ment (Dittmann & Jensen, 2014). However, to the
best of our knowledge, AFIs have only been devel-
oped for adults, and we are not aware of any AFIs
focusing on increasing acceptance of PTSD
treatments.
Future studies should also investigate strategies to
better engage participants in qualitative research
who either never start treatment or discontinue pre-
maturely. Inviting them to participate in a brief inter-
view or write a short text about their experiences after
stopping the intervention – while oering additional
incentives – could improve outreach to this critical
target group. Incorporating their perspectives could
enhance treatment engagement and help identify con-
traindications that might prevent an IMI from being
eective due to poor fit. Moreover, using an iterative
development process and incorporating user feedback
regarding intervention design, structure, and technol-
ogy can address technical issues and identify which
content should be reviewed to prevent content over-
load and ensure its relevance. Likewise, it may be help-
ful to integrate successful recovery narratives,
particularly during the ‘challenging but helpful’
trauma processing phase, to foster intrinsic motiv-
ation and adherence to treatment. Indeed research
has shown that these can increase participants’ feelings
of connectedness, hope, and self-ecacy, ultimately
motivating their own engagement (Lyons et al.,
2021). Additionally, a motivational messaging system,
in which messages are delivered to participants by a
virtual agent with content developed by experts in
the field of PTSD therapy, has been shown to be eec-
tive in adult PTSD IMIs (Tielman et al., 2019) and
could also enhance motivation and trust in the therapy
process for youth.
Tailoring the IMI to individual needs likely involves
oering greater exibility in selecting therapeutic
techniques and the sequencing of sessions. However,
it should be noted that empirically-supported manua-
lized treatments for PTSD have a clear sequence of
treatment components. Adherence to these manuals
is strongly emphasised and the impact of changes to
the intervention components on its ecacy remains
unclear. To bridge the gap between fidelity and exi-
bility, future IMI studies should whether investigate
personalised approaches, in which a case formulation
approach is used to implement evidence-based treat-
ment of PTSD, can be transferred to the digital setting
(Galovski et al., 2024). Our findings suggest varying
needs among youth regarding the intensity of thera-
peutic support, especially – but not exclusively –
during trauma processing, highlighting the need for
an individualised guiding approach. Oering optional
video-based sessions or integrating IMI into a blended
care approach could improve the fit for some partici-
pants. For others, these options may mitigate their
need for autonomy and independence, thus negatively
impacting engagement and eliminating the benefits of
low-threshold self-help. More research is needed to
explore ways to oer personalised therapeutic support
while maintaining IMI scalability. This should include
identifying factors that inuence the need for varying
levels of guidance for trauma-exposed youth and
enabling early intervention adaptation, like in a
stepped care approach, to better meet individual
needs.
4.3. Conclusion
This study is the first to evaluate youths’ perspectives
on the feasibility of a trauma-focused IMI using
qualitative content analysis. The findings indicate
that the IMI was generally accepted and appreciated
in terms of design, structure, technology, and inter-
ventional components by the participants, supporting
ongoing research on trauma-focused IMIs for youth.
Overall, more positive than negative aspects of IMIs
were reported, and the non-trauma processing com-
ponents were globally perceived as helpful. Trauma
processing presents various challenges similar to
those in face-to-face therapy. However, like in face-
to-face therapy, these challenges can often be over-
come through understanding the therapy rationale,
thus making trauma processing a commonly recog-
nised active factor in the treatment. Further research
is needed to optimise the degree of individualisation
of the intervention and the intensity of therapeutic
support.
12 C. SCHULTE ET AL.
Acknowledgements
We would like to acknowledge Hannah Illerhaus, Marlene
Meyer and Marlena Kalinke for the transcription of the
audio recordings and Jasmina Weiss for her contribution
to the qualitative data analyses.
Disclosure statement
No potential conict of interest was reported by the authors.
Funding
This work was supported by the Federal Ministry of Edu-
cation and Research under [grant number 01KR1804D].
Data availability statement
Access to the anonymized interview transcripts and the
interview guide (in German) can be provided to fellow
researchers upon request, depending on specified data
security and data exchange regulations.
Authors’ contributions
All authors have read and approved the final manuscript.
DE received funding for this study. CeS drafted the original
design of the study for the grant application and advised CS
and ACZ on the design of the intervention. ACZ and CS
developed and implemented the intervention and the
study and developed the interview guide for the qualitative
interviews. CS conducted and coded the interviews, drafted
the manuscript, and was supervised by ACZ.
Ethics approval and consent to participate
The DGPs approved the research protocol (DGPs, the Society,
EbertDavidDaniel2020-09-16-VA). The consent to participate
is available in German and was reviewed by the Institutional
Review Board (DGPs). The study is registered in the German
Clinical Trial Registry (GCTR, DRKS00023341), registered
on 20 July 2021, https://www.drks.de/drks_web/navigate.do?
navigationId=trial.HTML&TRIAL_ID=DRKS00023341
Consent for publication
All authors have read the manuscript and approved its
publication.
Date of first enrolment
04 August 2021.
ORCID
Christina Schulte http://orcid.org/0009-0003-1674-4872
Anna-Carlotta Zarski http://orcid.org/0000-0002-0517-6668
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