Your goal is to extract structured information from the user's input that matches the form described below. When extracting information please make sure it matches the type information exactly. Do not add any attributes that do not appear in the schema shown below.

```TypeScript

 { // Information on the clinical trial characteristics from the abstract
 conditions: string // The condition or disease being treated in the clinical trial
 drug_or_intervention: string // The drug or intervention used in the clinical trial
}
```


Please output the extracted information in JSON format. Do not output anything except for the extracted information. Do not add any clarifying information. Do not add any fields that are not in the schema. If the text contains attributes that do not appear in the schema, please ignore them. All output must be in JSON format and follow the schema specified above. Wrap the JSON in <json> tags.



Input:Prevention of postoperative hypocalcemia with routine oral calcium and vitamin D supplements in patients with differentiated papillary thyroid carcinoma undergoing total thyroidectomy plus central neck dissection.  Routine oral calcium and vitamin D supplementation may prevent hypocalcemic crisis, but its efficacy has not been studied in patients undergoing thyroidectomy plus central neck dissection (CND). The authors therefore prospectively evaluated the clinical usefulness of routine oral calcium and vitamin D supplementation for prevention of hypocalcemia after total thyroidectomy and CND. Of 197 patients with differentiated papillary thyroid carcinoma, 49 underwent total thyroidectomy alone, and 148 underwent total thyroidectomy plus CND. The latter were randomized to oral calcium (3 g/day) plus vitamin D (1 mg/day) (Group A, n=49), calcium alone (Group B, n=49), or no supplements (Group C, n=50). Hypocalcemic symptoms, serum calcium, and parathyroid hormone (PTH) levels were compared among the groups. Group C had significantly higher incidences of symptomatic (26.0% vs 6.1%; P<.015) and laboratory (44.0% vs 14.3%; P<.015) hypocalcemia than the group without CND. The incidences of symptomatic and laboratory hypocalcemia were significantly decreased in Groups A (2.0% and 8.2%, respectively) and B (12.2% and 24.5%, respectively) (P<.05). Serum calcium levels decreased in most patients after surgery, but recovered earliest in Group A. Hypercalcemia and PTH inhibition did not occur in gs A and B. Compared with total thyroidectomy alone, CND significantly increases the rate of postoperative hypocalcemia, which can be prevented by routine postoperative supplementation with oral calcium and vitamin D. Output:
{'conditions': 'Hypocalcemia', 'interventions': 'Dietary Supplement: Oral calcium plus vitamin D|Dietary Supplement: Oral calcium alone'}