Please assess the completion status of the following clinical trial:

Trial Title: Comparison of Postoperative Outcomes Between Surgeries Anaesthetized With Propofol and Inhalational Anaesthetics

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

Eligibility Criteria:
Inclusion Criteria:~1. Postoperative outcomes from Acute Pain Service data bank between Jan 2015 and Dec 2017 in Queen Mary Hospital would be retrieved;~2. Surgeries with general anaesthesia by either propofol or inhalational anaesthetics.~Exclusion Criteria:~1. Essential data missed;~2. Surgical types with small sample size below 30 for the data collection period.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: None

Study Arms:
- Group propofol (Type: None): Patients who had surgeries and were anaesthetized with propofol at Queen Mary Hospital, Hong Kong from Jan 2015 to Dec 2017
- Group inhalation anaesthetics (Type: None): Patients who had surgeries and were anaesthetized via inhalation at Queen Mary Hospital, Hong Kong from Jan 2015 to Dec 2017

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