Please assess the completion status of the following clinical trial:

Trial Title: Safety and Effectiveness of Apixaban Compared to Warfarin in Secondary Prevention in Patients With Atrial Fibrillation

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

Eligibility Criteria:
Inclusion Criteria:~Patients must meet all the following selection criteria~1. Patients registered in the Medical Data Vision (MDV) database 2008 though 2021.~2. Patients newly with non-valvular atrial fibrillation~3. Patients who newly receive warfarin or apixaban after diagnosis of NVAF~4. Age 20 years or older on the index date~5. Patients who have a history of stroke or transient ischemic attack (TIA) are inclusion criteria only for secondary prevention cohort, otherwise patients will be concluded in the primary prevention cohort.~Exclusion Criteria:~Patients who meet the following exclusion criteria will be excluded from this study~1. Patients with a diagnosis of valvular AF (standard disease code: 8846941), postoperative AF (8847772), AF associated with mechanical valve malfunction (T82.0), mechanical complication of heart valve prosthesis (T82.0), or rheumatic AF (I05-I09) during the baseline period.~2. Patients with a diagnosis of venous thromboembolism (VTE) during the baseline period~3. Patients who are prescribed any anticoagulants before index date.~4. Patients who are prescribed anticoagulants other than warfarin and apixaban on the index date~5. Patients who are continuously hospitalized due to the first incidence of stroke or other serious diseases.

- Gender: ALL
- Minimum Age: 20 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Warfarin cohort (Reference) (Type: None): Patients with NVAF treated with warfarin
- Apixaban cohort (Type: None): Patients with NVAF treated with apixaban

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