Database: thrombosis_prediction
Question: For patients with abnormal platelet level, state the number of patients with lower than normal range. How is it compare to the number of patients with higher than normal range?
SQL: SELECT SUM(CASE WHEN T2.PLT <= 100 THEN 1 ELSE 0 END) - SUM(CASE WHEN T2.PLT >= 400 THEN 1 ELSE 0 END) FROM Patient AS T1 INNER JOIN Laboratory AS T2 ON T1.ID = T2.ID