The purpose of the CROP study is to investigate the potential to cultivate psychological resources and resilience in childhood cancer patients and their family members using a mobile phone-based intervention.

The feasibility study aims to evaluate the implementation and participant experience of the digital intervention and register psychological outcome measures preliminary evidence for its acceptability, feasibility, and potential beneficial effects.

The feasibility study (CROP) will recruit 20 youths with newly diagnosed cancer (10-18 y) and family members for participation in a 12-week digital intervention to cultivate psychological resources.

Investigators will recruit an equal number of pediatric patients with other chronic conditions to an observational comparison group to indicate the influences on participation and outcome from the oncology care context.

Investigators will obtain informed consent from all participants. Upon inclusion in the study, participants will start getting a text message every day for 12 consecutive weeks. The texts will contain links to a digital platform on which participants will complete an exercise in either self-reflection or guided mindfulness meditation.

The psychological training program is based on 12 modules with evidence-based treatments in other medical contexts and age groups. The practices are based on acceptance, commitment, re-appraisal, meaning and purpose, expressive writing, narrative processes, mindfulness, compassion, equanimity, and gratitude. The combination of practices and the implementation in pediatric oncology has not been studied earlier.

The cancer patients will be recruited during the first month after diagnosis, meet with an instructor during 2-4 start-up meetings, and thereafter practice on their own or with participating family members.

The pediatric patients with chronic diseases will be recruited during a follow-up visit to an out-patient clinic and meet with an instructor during 2-4 start-up meetings, and thereafter practice on their own or together with participating family members.

Investigators will address the primary research question of the feasibility of the intervention by investigating participant activity data, written evaluations of the experience of participation, and through phone interviews of participants.

Secondary research questions, such as preliminary data on changes in mental health and psychological distress, will be investigated with self-report questionnaires.

Inclusion Criteria:

• Newly diagnosed cancer
• Chronic pediatric disease

Exclusion Criteria:

• Severe crisis reaction
• Late-stage palliative care
• Severe intellectual disability
• Psychiatric disease hindrance
• Participation in other study with psychological intervention

Study data will be made available upon reasonable request from other researchers.

Collection of data and analysis will be made by researcher with limited knowledge of participant status.