Anxiety is an emotion related to risk assessment that is evoked in situations where danger is uncertain, either because the context is novel or the danger stimulus was present in the past (Graeff, 2007). Child anxiety following hospitalization is a multidimensional phenomenon, characterized by biological and psychological aspects and triggered by the stressful and threatening process of being inserted in a hospital environment (Gomes & da Nóbrega, 2015). Hospitalized children have to leave their normal family and social environment, interrupt their recreational activities, live with strangers, and be subjected to invasive and painful procedures (Gomes et al., 2016). Child anxiety triggered by this hospitalization experience results in negative short- and long-term development consequences (Gomes et al., 2016; Gomes & da Nóbrega, 2015).

The life changes experienced by children and their families due to the hospital environment can generate fear, anxiety, and stress in children and adolescents, affecting their overall biopsychosocial development (Farias et al., 2021; Garcia De Avila et al., 2022; Gomes et al., 2016; Gomes & da Nóbrega, 2015). Therefore, it is important for family members to apprehend the institutional culture and for hospital rules and routines to be adaptable and flexible to humanize care (Farias et al., 2021). Families believe that they are favored when health professionals adapt the hospital's rules and routines to meet a special need of the child or a family caregiver and that this does not compromise the normal functioning of the sector, preserving the institution's specificities (Farias et al., 2021). A mixed-methods study of 17 patients in a children's hospital in the United States has shown that it is not always possible to avoid the negative experiences of pain and discomfort related to medical procedures and illness; however, it is possible to implement support strategies to make hospital experiences more comfortable for children (Claridge & Powell, 2022). These support strategies for hospitalized children include having their parents nearby; interacting with their peers; having opportunities to leave their room; and receiving care from supportive nurses, doctors, and child life specialists (Claridge & Powell, 2022). In addition, children can provide helpful insight into their hospital experiences regarding the aspects of hospitalization that are difficult and those that make their stay easier (Claridge & Powell, 2022).

Similarly, a literature review has indicated the need for action by nursing teams to contribute to the relationship established between children and their guardians (Azevêdo et al., 2017). Furthermore, systematized nursing care strategies and plans for the care of children and their families should be developed and implemented to promote comprehensive care and minimize the impacts of hospitalization on the children's well-being. In the pediatric context, healthcare professionals commonly address only parents when providing information about children's health conditions; this may further impair children's experience of the hospitalization process. Therefore, nurses should use appropriate language to communicate with their target audience, ensuring that it is child- and family-centered (Ford et al., 2018). Researchers recommend that healthcare professionals be trained to assess children's anxiety with an applied tool to monitor changes in behaviors during treatment or follow-up and to ensure appropriate management thereof (Rodrigues et al., 2021).

Important aspects that must be considered in an instrument to assess childhood anxiety include self-reports, pictorial support, and the instrument's psychometric properties (Nilsson et al., 2021). Self-reports are especially important for emotional and abstract concepts, such as anxiety (Namisango et al., 2020). Thus, they should be used in the assessment of anxiety in children, as children are the best sources of information about themselves (Darcy et al., 2019). Pictorial support can facilitate children's emotional expression and help them understand the instrument's questions (Nilsson et al., 2015). Furthermore, in situations where children do not understand the questions of an anxiety instrument or may not understand their healthcare provider due to language barriers, alternative strategies such as pictorial support play a crucial role in communicating their anxiety (Mahakwe et al., 2021). Specifically, valid, reliable, and age-appropriate measurement instruments that provide pictorial support are crucial for measuring anxiety levels in children and better guide the selection of appropriate interventions (Mahakwe et al., 2021).

A systematic review has identified the validated and reliable self-report instruments available for children aged 5–18 years to use in children with cancer in the hospital setting (Mahakwe et al., 2021). Eight instruments were identified, but most of the instruments lacked pictorial support. The Visual Analogue Scale (VAS) and Pediatric Quality of Life (PedsQL™) 3.0 Brain Tumor Module and Cancer Module proved to be useful in hospitalized children with cancer as they provide pictorial support (Mahakwe et al., 2021). The authors outlined that adapting these instruments to digital tools could make them more interesting for children (Mahakwe et al., 2021; Oh, 2023).

To the best of our knowledge, the Children Anxiety Questionnaire (CAQ) is an instrument that brings together all the crucial aspects for measuring child anxiety. The CAQ is a relatively new instrument for assessing self-reported anxiety in hospitalized children and adolescents, incorporates pictorial support, and can be used in nursing care for pediatric patients, especially in Brazil and Sweden. The CAQ in Brazilian Portuguese was recently validated and demonstrated satisfactory results among professionals and children (Rodrigues et al., 2021), and its psychometric properties have been studied in various contexts (Dias, 2021; Rodrigues, 2023).

Thus, this study aims to transpose the printed CAQ BR into a 2D digital format, validate this digital version with nurses and hospitalized children, and analyze the association between the printed and 2D digital formats.