You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

BACKGROUND: Maintaining standards of living donor liver transplantation (LDLT) can be a challenge during the corona virus disease 2019 (COVID-19) pandemic. Center-specific protocols have been developed and transplant societies propose limiting elective LDLT. We have looked at outcomes of LDLT during the pandemic in an exclusively LDLT center. METHODS: Patients were grouped into pre-COVID (January 2019-February 2020) (n = 162) and COVID (March 2020-January 2021) (n = 53) cohorts. We looked at patient characteristics, 30-day morbidity, and mortality. Outcomes were also assessed in donors and recipients who underwent surgery after recovery from COVID-19. RESULTS: The average number of transplants reduced from 11.5/month to 4.8/month. Fewer patients with MELD > 20 underwent LDLT in the COVID cohort (41.3% versus 24.5%, P = 0.03). Out of nine patients with a positive pretransplant COVID-19 PCR, there were 2 (22.3%) deaths on the waiting list. Seven patients underwent LT after recovery from COVID-19 with one 30-day mortality due to biliary sepsis. Three donors with positive COVID-19 PCR underwent uneventful donation after testing negative for COVID-19. No significant difference in 30-day survival was observed in the pre-COVID and COVID cohorts (93.2% versus 90.6%) (P = 0.3). Out of two recipients who developed COVID-19 pneumonia within 30 days after LT, there was one mortality. The 1-year survival for the entire cohort with a MELD cutoff of 20 was 90% and 84% (P = 0.2). CONCLUSION: Despite comparable outcomes, fewer sick patients might undergo LDLT during the pandemic. Individuals recovered from COVID-19 might be safely considered for donation or transplantation.
["Prevention"]