Research Article Relationships between executive functions and occupational performance of children with medulloblastoma G€ ozde € Onal, Meral Huri Abstract Introduction: This study examines executive functions and occupational performances of children with medulloblastoma and children with typical development. The aim was to compare the executive function and occupational performance levels of children with medulloblastoma and children with typical development and to investigate the relationship between the executive function and occupational performance levels of children with medulloblastoma. Method: Parents of 105 children (6–12 years) completed the Childhood Executive Function Inventory. A total of 105 children were administered the Canadian Occupational Performance Measurement to obtain information on occupational performance areas. Executive functions and occupational performance levels of children with medulloblastoma (n ¼ 52) and typical development (n ¼ 53) were compared. Correlation analysis was conducted between the executive functions and occupational performances of children with medulloblastoma. Results: Executive function and occupational performance levels of children with medulloblastoma were lower than those with typical development. Significant relationships were found between the executive functions and occupational performances of children with medulloblastoma (p < 0.05, p < 0.001). Conclusion: It is clear that the executive functions of children with medulloblastoma significantly affect their occupational performance level. Client-centered, occupation-oriented cognitive therapy interventions prepared according to occupational ther- apy theories and models might be useful to increase the occupational performance level of children with medulloblastoma. Keywords Medullablastoma, cancer, executive functions, occupational performance, activities of daily living, occupational therapy Received: 3 March 2020; accepted: 10 June 2020 Introduction Medulloblastoma (MB) is the most common malignant tumor in childhood. It accounts for about 20% of all childhood brain tumors and about 64% of embryonal tumors (Doussouki et al., 2019). Common types of treat- ment for MB include local radiotherapy, craniospinal radiotherapy, chemotherapy and surgical operation. These treatments cause serious neurocognitive deficits in children (Ribi et al., 2005). These neurocognitive def- icits can be seen in the areas of intelligence, attention, processing speed, memory and executive function (Doussouki et al., 2019). Executive functions (EF) require different cognitive processes, including initiation, planning, decision- making, cognitive flexibility, reasoning, and self- regulation for effective and appropriate behavior, and these functions shape various routine and non-routine activities of daily living (ADL). Reduced executive func- tions also inhibit the ability to execute tasks with multi- ple steps (Ribi et al., 2005). Neurological and neurocognitive deficits affect areas such as adaptation to social life, academic achievement and independence in daily life, and these deficits can continue from childhood into adulthood (LeBaron et al., 1988). Studies show that the executive function deficits of the survivors of childhood MB affect independent life in adulthood (Brinkman et al., 2012; Kieffer et al., 2019). Studies show that the cumulative effects of disease and treatment factors inhibit brain development, and children with MB have deficits especially in the area of working memory (WM) (Knight et al., 2014; Palmer, et al., 2013). WM represents an important aspect of neu- rocognition and can be defined as a system with a limited capacity to temporarily hold information (Repovs and Baddeley, 2006). Memory is very important for record- ing new information and gaining new knowledge and skills. Therefore, it is directly associated with the aca- demic achievement of children (Nesbitt et al., 2015). EF are not composed of just WM; they involve a wide range of processes. These processes include planning, inhibitor control, regulation, goal-setting and problem-solving. Occupational Therapy Department, Hacettepe University, Ankara, Turkey Corresponding author: Meral Huri, Hacettepe University, Ankara, Turkey 06230. Email: meralhuri@yahoo.com British Journal of Occupational Therapy 0(0) 1–8 ! The Author(s) 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0308022620939859 journals.sagepub.com/home/bjot