instruction: what are the three most common lab tests for the patients of age 50s since 2102?
response: SELECT d_labitems.label FROM d_labitems WHERE d_labitems.itemid IN (SELECT t1.itemid FROM (SELECT labevents.itemid, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM labevents WHERE labevents.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.age BETWEEN 50 AND 59) AND STRFTIME('%y', labevents.charttime) >= '2102' GROUP BY labevents.itemid) AS t1 WHERE t1.c1 <= 3)