To determine the effect of mandala art therapy (coloring) on nausea, vomiting, pain and anxiety in children receiving outpatient chemotherapy. The concept of cancer is used to describe a group of diseases that start from a single cell and show uncontrolled growth, proliferation and spread to surrounding tissues. The cooperation of the family and the healthcare team plays a major role in the success of the treatment. Surgical treatment, radiotherapy and chemotherapy are applied in its treatment. Art therapy, a method of distraction, is used to prevent pediatric oncology patients from focusing on the pain and stressful life events they experience. By having children do artistic activities in the hospital room, nurses can reduce symptom management, social isolation, and long-term negative social effects.

Cancer treatment in children is determined according to the type of cancer, its stage and the child's general health condition. Treatment options include the following; chemotherapy, radiotherapy, surgery, immunotherapy and targeted therapy. The following problems are observed in children receiving chemotherapy in the short and long term: fever, fatigue, weight loss, pain, fatigue, anxiety, nausea and vomiting, changes in sleep and mood. 91% of oncology patients have benefited from Complementary and Alternative Medicine (CAM), such as art, to improve their general health, and painting, painting, music and dance, and mind-body therapies have been shown to have positive effects on the quality of life in pediatric oncology patients.

Art therapy in the pediatric oncology patient population. The American Art Therapy Association (AATA) (2013) defines art therapy as healing. Increasing the physical, mental and emotional well-being of individuals is considered as creative interventions of art production. These interventions have been widely used as alternative treatments for a variety of conditions, including cancer.

Although there is a significant amount of research on the effects of art therapies, there is a lack of research in the existing literature regarding their specific effects on symptoms such as nausea, vomiting, pain, and anxiety. However, the effects on quality of life are generally given more attention.

Among the art therapies; Mandala art therapy is a type of art therapy using circular patterns and symbols. In this therapy, participants explore their inner world and express their emotions by creating their own mandates. It gives individuals the opportunity to concretize the complex and abstract thoughts in their minds caused by their painful experiences. Emotions and thoughts are spontaneously embedded in artistic products such as sculpture, music, painting, marbling and mandala. Mandala therapy improves creativity and problem-solving skills by increasing emotional awareness and expression.

As a result, mandala art therapy can be used in the treatment of many different problems such as stress, anxiety, depression, trauma and chronic disease, as well as in the management of symptoms.

To determine the sample size of the study, the power of the study was calculated with the G-Power 3.1.9.2 program using the confidence interval and effect size parameters. 80% power, 95% confidence interval and effect size of 0.5 or more. In the G-Power 3.1.9.2 program, the total sample size was calculated as 48 (24+24) based on 0.05 significance, 0.80 large effect and 80% power. However, considering the 10% loss and taking into account the parametric test assumption, the sample number of each group was determined as 30 people in the intervention group and 30 people in the control group, for a total of 60 people.

Inclusion Criteria:

• Being at the pediatric chemotherapy clinic to receive outpatient chemotherapy
• Receiving daily chemotherapy
• Those who agreed to participate in the research
• Mother and child must know Turkish
• The child knows colors

Exclusion Criteria:

• Having a mental health problem (preventing the use of Mandala therapy coloring technique)
• Having a disability that prevents you from seeing or using your hand (a condition that prevents you from using the Mandala therapy coloring technique)

Double (Participant, Outcomes Assessor)