Cross-sectional Study of Sleep Disturbance in Hong Kong Children With Cancer Comparing With Healthy Counterparts and Children With Other Chronic Diseases

Inclusion Criteria: 1. Children with Cancer (n=50) Participants in this group will be children with a confirmed cancer diagnosis, such as leukemia, lymphoma, or solid tumors, who are currently hospitalized for treatment at the inpatient oncology wards of Hong Kong Children's Hospital. Eligible participants must be actively receiving cancer-directed therapy (e.g., chemotherapy, radiation) during their hospital stay. Inclusion criteria require that participants, or their parents or legal guardians as proxies, can provide accurate reports about sleep patterns, either through self-assessment or observation, ensuring reliable data collection. This group will capture the acute impact of cancer treatment and hospitalization on sleep, a critical focus of the study. 2. Children with Other Chronic Illnesses (n=50) This group will comprise children diagnosed with chronic conditions other than cancer, such as asthma, type 1 diabetes, or chronic kidney disease, recruited from the cardiac, nephrology, and mixed wards of Hong Kong Children's Hospital. These illnesses are selected for their known potential to disrupt sleep-e.g., nocturnal asthma symptoms or glucose instability-while differing in pathophysiology from cancer. Participants must be under active management for their condition and currently hospitalized, but must not have a history of primary sleep disorders (e.g., narcolepsy, obstructive sleep apnea) unrelated to their chronic illness. This criterion ensures that observed sleep disturbances are attributable to the chronic condition rather than pre-existing sleep pathology. 3. Healthy Children (n=50) The healthy control group will be of adequate sample size. These include siblings of pediatric patients (both oncology and non-oncology wards), and children of hospital staff (e.g., nurses, administrative personnel). Inclusion criteria require no history of chronic illness, psychiatric disorders, or known sleep conditions. Parental consent and child assent will be obtained for all participants. Exclusion Criteria: Across all three groups, children will be excluded if they are not Chinese and are in intensive care units. Children who exhibit severe cognitive impairments that preclude accurate reporting of sleep experiences, either by themselves or their parents or legal guardians, will be excluded. Additionally, participants with neurological conditions known to independently affect sleep, such as epilepsy or cerebral palsy, will be excluded to avoid confounding the primary relationship between chronic illness and sleep disturbances. The use of sedative medications unrelated to the participant's primary condition (e.g., for behavioral management rather than cancer treatment) will also disqualify participants, as these could artificially alter sleep patterns and obscure study outcomes. These exclusion criteria ensure that sleep disturbances observed are primarily linked to the participants' health status rather than extraneous factors.