California Cancer Reporting System Standards, Volume III

APPENDIX 8  CALCULATION OF SURVIVAL TIME

If any of the following conditions is true:

• Date of Last Contact is NOT a complete date (18000101-23001231)

• Date of Diagnosis is NOT a complete date (18000101-23001231)

• Date of Last Contact and Date of Diagnosis are complete dates, but Date of Last Contact < Date of Diagnosis

Then set Survival Time to 99999 and stop here.

If Date of Last Contact = Date of Diagnosis,

Then set Survival Time to 00000 and stop here.

Otherwise, convert Date of Last Contact and Date of Diagnosis into three-digit Julian dates (JJJ), taking into account leap years (add 1 more day for leap year dates after February), and perform the following procedure to calculate the number of days the patient has survived since her/his diagnosis:

1. Determine the number of leap years and regular years in between the two years.

2. Compute the number of days in the years in between the two years:

3. (number of leap years * 366) + (number of regular years * 365)

Compute SURVIVAL-TIME:

If Date of Diagnosis CCYY is a leap year

Then SURVIVAL-TIME = 366 - JJJ (Date of Diagnosis)

+ number of days in the years in between the two years

+ JJJ (Date of Last Contact)

Else SURVIVAL-TIME = 365 - JJJ (Date of Diagnosis) I+ number of days in the years

Historical Changes