Table 1 Inclusion and exclusion criteria for the NiCK study

Inclusion criteria

Age 8 – 25 years

English is primary language for participant (most neurocognitive measures standardized only in English). Parent completing questionnaires must be proficient in English.

CKD subjects: Stage 2–5 CKD (eGFR < 90 mL/min/1.73 m²), including dialysis and transplant patients

Control subjects: Healthy siblings or individuals matched in age and insurance status

Exclusion criteria

Conditions that would prohibit MRI: certain types of body metal; claustrophobia

Auditory impairment (that cannot be corrected by a hearing aid) that would significantly impede the valid collection of test measures

History of traumatic brain injury or other significant medical or neurological abnormality affecting motor or higher cortical functioning (e.g. seizure disorder, genetic syndromes, systemic diseases that can affect the brain such as sickle cell disease, cerebral lupus, spina bifida, gestational age below 32 weeks, or perinatal injury)

Profound developmental disability or sensory-motor difficulties that would preclude valid use of diagnostic instruments or scanning procedures.

A severe DSM IV-TR Axis I disorder or other psychiatric symptoms that would interfere with the participant’s ability to participate in the study (e.g., active psychosis)

Known drug or alcohol use within 24 hours of any assessment

Pregnancy (because of potential risk of MRI to the unborn fetus).