the day of begining head and neck radiotherpay
the year of begining head and neck radiotherpay
case birthday
gender(0:female，1:male)
age(years)
residual area (1:Northern 2:Central 3:Southern 4:Eastern)
income or social-economic sastus(1:income≦17,500 2:17,500<income≦25,000 3:income≧25,000)
ICD-9 code
Tumor origin area (0:non-oral lesion、1:oral lesion)
dead or not (0:still alive、1:dead)
Date of death
Observation end day(2013/12/31)
the period from index date to observation end date (years)
depression diagnosis between index date to obseration end date (0:no depression ,1: yes)
after index day, the depression diagnosis date
6 months around index day, case receiving chemotherpay or not (0=no、1=yes)
before index date, cerebrovascular accident history or not (0:no、1:yes)
before index date,immune disease history or not (0:no、1:yes)
before index date,Dementia history or not (0:no、1:yes)
before index date,Parkison disease history or not (0:no、1:yes)
before index date,diabetes mellitus history or not (0:no、1:yes)
before index date,hypertension history or not (0:no、1:yes)
before index date,hyperlipidemia history or not (0:no、1:yes)
before index date,coronary artery disease history or not (0:no、1:yes)
before index date,Depression history or not (0:no、1:yes)
before index date,on dialysis history or not (0:no、1:yes)
3 months around index day, case receiving head and neck excisional tumor surgery or not (0=no、1=yes)