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:

INTRODUCTION: As a result of the COVID-19 pandemic, the health care systems around the world have been overburdened resulting in significant reduction of planned surgical procedures such as bariatric surgeries. The primary aim of this study is to assess the influence of the COVID-19 national lockdown in Poland on the short-term outcomes and intraoperative course of bariatric patients in a high volume IFSO certified bariatric center. MATERIAL & METHODS: This is a retrospective analysis of 158 bariatric surgery patients, who underwent bariatric procedures either prior to or after the first national lockdown in Poland. The patients were categorized as pre-lockdown group and the post-lockdown group, each comprising of 79 patients. RESULTS: The post-lockdown group had significantly lower operative weight (105.76 vs 114.25, p = 0.012) and BMI (36.99 vs 39.93, p = 0.005) compared to pre-lockdown group. The primary length of stay was significantly longer in the post-lockdown group (3.04 vs 2.44, p = 0.001). The post-lockdown group had significantly lower mean CCI score (1.90 vs 6.67, p = 0.046) and less short-term readmissions post-discharge (0 vs 8.86, p = 0.007) than pre-lockdown group. CONCLUSION: The post-lockdown group was found to have lower body weight and BMI on the day of the operation than those operated prior to the lockdown. These findings are conflicting to previous research assessing weight changes during lockdowns. Since the qualification criteria and order of operations were similar and pre-defined for both groups, possible explanations for these findings are higher patient motivation due to COVID-19 fears and longer preparation period due to elective surgery postponement. We encourage bariatric centers globally to assess the effect of national lockdowns on the patient profiles as well as the psychological and behavioral impact on the bariatric cohort.
["Prevention"]