Please assess the completion status of the following clinical trial:

Trial Title: Nicotine Receptor Levels and Smoking Cessation

Study Design Characteristics:
- Allocation: None
- Intervention Model: None
- Observational Model: COHORT
- Primary Purpose: None
- Time Perspective: PROSPECTIVE
- Masking: None
- Phase: None
- Number of Arms: None

Eligibility Criteria:
Exclusion Criteria:~In addition to the exclusion criteria used for PNAT trial \[NCT01314001\], participants in this trial will be excluded if they meet the following criteria:~Imaging-Related Exclusion Criteria:~1. Weigh over 299 lbs.~2. Self-reported history of head trauma or brain (or CNS) tumor.~3. Self-reported history of claustrophobia (contraindicated for PET and MRI).~4. Cochlear implant or bilateral hearing aids.~5. Pacemakers, certain metallic implants, or presence of metal in the eye as contraindicated for MRI.~6. History of gunshot wound (including BB guns).~7. Circumstances or conditions that may interfere with magnetic resonance imaging (MRI).~8. CO reading greater than 15ppm at the PET Scan Session (or at least a 50% reduction from the PNAT Intake Session).~9. BrAC reading greater than or equal to 0.01 at the PET Scan Session.~10. Positive urine drug screen for cocaine, phencyclidine, amphetamines, methamphetamines, tricyclic antidepressants, opiates, methadone, benzodiazepines, or barbiturates at the PNAT Intake Session or PET Scan Session.~11. Positive urine pregnancy (females only) screen at the PET Scan Session and/or MRI Scan Session.~12. Inability to give blood at the PET Scan Session (blood samples are required to analyze PET data).~13. Prior exposure to radioactive tracers in imaging studies or for medical reasons may be exclusionary.~General Exclusion Criteria:~1. Any medical condition, illness, disorder or concomitant medication that could compromise participant safety or treatment, as determined by the Principal Investigator or Co-investigators.~2. Inability to provide informed consent or complete the study procedures within 10 hours and/or correctly, as determined by the Principal Investigator or Co-investigators.~3. Any physical or visual impairment that would prevent completion of the cognitive tasks.~4. Participation (within the last 6 months) in other studies at our center involving similar cognitive testing procedures.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 65 Years
- Healthy Volunteers: t

Study Arms:
- Slow metabolizers (Type: None): Individuals with an NMR \<0.26 will be classified as slow metabolizers.
- Normal metabolizers (Type: None): Participants with an NMR \>= 0.26 will be classified as normal metabolizers.

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