instruction: count the number of patients who were diagnosed with asphyxiation/strangulat and who didn't come back to the hospital in the same month in the last year.
response: SELECT (SELECT COUNT(DISTINCT t1.subject_id) FROM (SELECT admissions.subject_id, diagnoses_icd.charttime FROM diagnoses_icd JOIN admissions ON diagnoses_icd.hadm_id = admissions.hadm_id WHERE diagnoses_icd.icd9_code = (SELECT d_icd_diagnoses.icd9_code FROM d_icd_diagnoses WHERE d_icd_diagnoses.short_title = 'asphyxiation/strangulat') AND DATETIME(diagnoses_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) AS t1) - (SELECT COUNT(DISTINCT t2.subject_id) FROM (SELECT admissions.subject_id, diagnoses_icd.charttime FROM diagnoses_icd JOIN admissions ON diagnoses_icd.hadm_id = admissions.hadm_id WHERE diagnoses_icd.icd9_code = (SELECT d_icd_diagnoses.icd9_code FROM d_icd_diagnoses WHERE d_icd_diagnoses.short_title = 'asphyxiation/strangulat') AND DATETIME(diagnoses_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) AS t2 JOIN admissions ON t2.subject_id = admissions.subject_id WHERE t2.charttime < admissions.admittime AND DATETIME(admissions.admittime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year') AND DATETIME(t2.charttime, 'start of month') = DATETIME(admissions.admittime, 'start of month'))