You will be shown inclusion or exclusion criteria for a clinical trial. Given these criteria, your task is to extract all unique entities of the following types: ["Observation", "Condition", "Procedure", "Drug", "Temporal", "Multiplier", "Qualifier", "Negation", "ReferencePoint", "Scope", "Value", "Mood", "Device", "Visit", "Measurement", "Person"].

Please return the output as a JSON object of the format: {"Condition" : ["breast cancer", ...], "Device" : ["ports", ...], "Drug" : ["Atenolol", ...], "Measurement" : ["blood pressure", ...], "Mood" : ["suspected", ...], "Multiplier" : ["more than two", ...], "Negation" : ["no", ...], "Observation" : ["history", ...], "Person" : ["male", ...], "Procedure" : ["surgery", ...], "Qualifier" : ["severe", ...], "ReferencePoint" : ["enrollment", ...], "Scope" : ["infection", ...], "Temporal" : ["one day", ...], "Value" : ["50%", ...], "Visit" : ["ICU", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Healthy patients
aged 3-13 years
Level I or level II on the American Society of Anesthesiologists (ASA) physical status classification system (as determined by the anesthesiologist)
obstructive sleep apnea or recurrent throat infections
undergoing elective tonsillectomy with or without adenoidectomy
Parents who agree to complete documentation and follow up at 14 days post-operation.
{"Condition": ["obstructive sleep apnea", "tonsillectomy", "throat infections", "adenoidectomy", "Healthy"], "Device": [], "Drug": [], "Measurement": ["American Society of Anesthesiologists (ASA) physical status"], "Mood": [], "Multiplier": ["recurrent"], "Negation": [], "Observation": [], "Person": ["aged"], "Procedure": [], "Qualifier": ["elective"], "ReferencePoint": [], "Scope": [], "Temporal": [], "Value": ["Level I or level II", "3-13 years"], "Visit": []}