Please assess the completion status of the following clinical trial:

Trial Title: Large-scale Brain Organization During Cognitive Control in ADHD

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: CROSSOVER
- Observational Model: None
- Primary Purpose: BASIC_SCIENCE
- Time Perspective: None
- Masking: DOUBLE
- Phase: PHASE4
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Between 8-12 years old~* Diagnosis of ADHD (for ADHD group); ADHD group only can have comorbid Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) diagnoses of oppositional defiant disorder, conduct disorder, depressive disorders, or anxiety disorders~* ADHD subjects must never have been treated with medication for their ADHD~Exclusion Criteria:~* Wechsler Intelligence Scale for Children-Fifth Edition Full-Scale Intelligence Quotient (IQ) \< 80~* Wechsler Individual Achievement Test-Third Edition Word Reading \< 85~* Any neurologic or developmental disabilities~* Any reading or learning disabilities~* Visual impairment that cannot be corrected-to-normal~* Color blindness~* Documented hearing impairment greater than 25 decibels (dB) loss in either year~* Have already gone through puberty (Tanner Stage II or higher)~* Medical contraindication to MRI~* Any psychoactive medication

- Gender: ALL
- Minimum Age: 8 Years
- Maximum Age: 12 Years
- Healthy Volunteers: f

Study Arms:
- Placebo, then Methylphenidate (Type: PLACEBO_COMPARATOR): All children with ADHD in this study will receive one dose of methylphenidate and one dose of placebo over the course of two sessions approximately one week apart (order randomized and double-blind).
- Methylphenidate, then Placebo (Type: EXPERIMENTAL): All children with ADHD in this study will receive one dose of methylphenidate and one dose of placebo over the course of two sessions approximately one week apart (order randomized and double-blind).

Based on this trial design, predict the completion outcome and termination type (if applicable).