instruction: count the number of patients whose insurance is private and procedure long title is percutaneous [endoscopic] gastrostomy [peg].
response: SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN procedures ON demographic.hadm_id = procedures.hadm_id WHERE demographic.insurance = "Private" AND procedures.long_title = "Percutaneous [endoscopic] gastrostomy [PEG]"