instruction: when did patient 52898 receive a test in the lab for the last time this month?
response: SELECT labevents.charttime FROM labevents WHERE labevents.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 52898) AND DATETIME(labevents.charttime, 'start of month') = DATETIME(CURRENT_TIME(), 'start of month', '-0 month') ORDER BY labevents.charttime DESC LIMIT 1