Age as of January 1st

  • All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    SQL DBA,SQL Server MVP(07, 08, 09) "It's a dog-eat-dog world, and I'm wearing Milk-Bone underwear." "Norm", on "Cheers". Also from "Cheers", from "Carla": "You need to know 3 things about Tortelli men: Tortelli men draw women like flies; Tortelli men treat women like flies; Tortelli men's brains are in their flies".

  • ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    I was wondering about that option. But I think birth date of January 1st is a special case. The "- 1" on the end may need to be in a CASE.

  • ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    Hi Scott, I could have sworn i tried something similar when i first started and it did not work, however i removed the minus one and sure enough it met the rules so far in testing. I really feel like i took something simple and really over thought it. Thanks again !

    ***SQL born on date Spring 2013:-)

  • ;
    WITH cte
    AS (
        SELECT CAST(BirthDate AS DATETIME) AS BirthDate
            ,CAST(ServiceDate AS DATETIME) AS ServiceDate
        FROM (
            VALUES
                    ( '01/01/1951', '2016-01-01'),
                    ( '01/01/1951', '2016-08-26'),
                    ( '01/02/1951', '2016-08-26'),
                    ( '08/26/1951', '2016-08-26'),
                    ( '11/01/1951', '2016-08-26'),
                    ( '01/01/1993', '2016-08-26'),
                    ( '01/02/1993', '2016-08-26')
            ) AS testdata(BirthDate, ServiceDate)
        )
    SELECT BirthDate
        ,ServiceDate
        ,DATEDIFF(YY, BirthDate, Jan1st) AS DiffYearsOnJan1
        ,DATEDIFF(YY, BirthDate, ServiceDate) AS DiffYearsOnServiceDate
        ,DATEDIFF(YY, BirthDate, Jan1st) - IIF(MONTH(BirthDate) = MONTH(Jan1st)
            AND DAY(BirthDate) = DAY(Jan1st), 0, 1) AS ActualAgeOnJan1
    FROM cte
    CROSS APPLY (
        SELECT DATEFROMPARTS(YEAR(ServiceDate), 1, 1) AS Jan1st
        ) _;


    BirthDate                ServiceDate              DiffYearsOnJan1   DiffYearsOnServiceDate  ActualAgeOnJan1
    1951-01-01 00:00:00.000  2016-01-01 00:00:00.000  65                65                      65
    1951-01-01 00:00:00.000  2016-08-26 00:00:00.000  65                65                      65
    1951-01-02 00:00:00.000  2016-08-26 00:00:00.000  65                65                      64
    1951-08-26 00:00:00.000  2016-08-26 00:00:00.000  65                65                      64
    1951-11-01 00:00:00.000  2016-08-26 00:00:00.000  65                65                      64
    1993-01-01 00:00:00.000  2016-08-26 00:00:00.000  23                23                      23
    1993-01-02 00:00:00.000  2016-08-26 00:00:00.000  23                23                      22

  • Shifting gears back to this part of the original post...

    So if I have a BirthDate = 11/30/1951 there age as a whole number as of January 1st of the service year. In this case any date within 2016
    So any date in 1951 should = 65
    any date in 1952 = 63

    Is that a mistake?  If not, please explain how 1951 could be 65 and 1952, which is just 1 year later, could be 2 years less in age?

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.


    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)

  • thomashohner - Tuesday, January 31, 2017 5:20 PM

    ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    Hi Scott, I could have sworn i tried something similar when i first started and it did not work, however i removed the minus one and sure enough it met the rules so far in testing. I really feel like i took something simple and really over thought it. Thanks again !

    It depends... maybe it is a mistake.  If someone is born in December of 1951, are they 0 years old or 1 year old on 1952-01-01 according to your requirements.  Same question if they were born in January of 1951.

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.


    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)

  • Sorry, my previous reply had a bug for computing ActualAgeOnJan1.  Corrected code:

    ;
    WITH cte
    AS (
        SELECT CAST(BirthDate AS DATE) AS BirthDate
            ,CAST(ServiceDate AS DATE) AS ServiceDate
        FROM (
            VALUES
                ('01/01/1951', '2016-01-01'),
                ('01/01/1951', '2016-08-26'),
                ('01/02/1951', '2016-08-26'),
                ('08/26/1951', '2016-08-26'),
                ('11/01/1951', '2016-08-26'),
                ('01/01/1993', '2016-08-26'),
                ('01/02/1993', '2016-08-26'),
                ('12/31/2015', '2016-08-26'),
                ('01/01/2016', '2016-08-26'),
                ('01/02/2016', '2016-08-26')
            ) AS testdata(BirthDate, ServiceDate)
        )
    SELECT BirthDate
        ,ServiceDate
        ,DATEDIFF(YY, BirthDate, Jan1st) AS DiffYearsOnJan1
        ,DATEDIFF(YY, BirthDate, ServiceDate) AS DiffYearsOnServiceDate
        ,DATEDIFF(YY, BirthDate, Jan1st) - IIF(YEAR(BirthDate) = YEAR(Jan1st)
            OR (
                MONTH(BirthDate) = MONTH(Jan1st)
                AND DAY(BirthDate) = DAY(Jan1st)
                ), 0, 1) AS ActualAgeOnJan1
    FROM cte
    CROSS APPLY (
        SELECT DATEFROMPARTS(YEAR(ServiceDate), 1, 1) AS Jan1st
        ) _;


    BirthDate   ServiceDate  DiffYearsOnJan1  DiffYearsOnServiceDate  ActualAgeOnJan1
    1951-01-01  2016-01-01   65               65                      65
    1951-01-01  2016-08-26   65               65                      65
    1951-01-02  2016-08-26   65               65                      64
    1951-08-26  2016-08-26   65               65                      64
    1951-11-01  2016-08-26   65               65                      64
    1993-01-01  2016-08-26   23               23                      23
    1993-01-02  2016-08-26   23               23                      22
    2015-12-31  2016-08-26   1                1                       0
    2016-01-01  2016-08-26   0                0                       0
    2016-01-02  2016-08-26   0                0                       0

  • dale_berta - Tuesday, January 31, 2017 5:43 AM

    ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    I was wondering about that option. But I think birth date of January 1st is a special case. The "- 1" on the end may need to be in a CASE.

    I can confirm that birth date of Jan 1 needs to be handled. If you're born on Jan 1, then you're 1 year on on Jan 1 of the next year. If you're born anywhere from Jan 2 through Dec 31, you're 0 years (and x months and days) on Jan 1 of the next year.

    To make this more obvious, I'll use test birth year of 2000, and service dates in 2001 and 2010:

    DECLARE @TestCases TABLE
    (
    BirthDate DATE
    ,ServiceDate DATE
    );
    INSERT INTO @TestCases
    VALUES ('2000-01-01', '2001-01-01'), ('2000-01-01', '2001-07-01')
       ,('2000-04-01', '2001-01-01'), ('2000-04-01', '2001-07-01')
       ,('2000-01-01', '2010-01-01'), ('2000-01-01', '2010-07-01')
       ,('2000-04-01', '2010-01-01'), ('2000-04-01', '2010-07-01');

    SELECT t.BirthDate
      ,t.ServiceDate
      ,YEAR(t.ServiceDate) - YEAR(t.BirthDate) AS OrigAgeOnJan1
      ,YEAR(t.ServiceDate) - YEAR(t.BirthDate)
       - CASE WHEN MONTH(t.BirthDate) = 1 AND DAY(t.BirthDate) = 1 THEN 0 ELSE 1 END
                    AS FixedAgeOnJan1
    FROM @TestCases AS t;

    The results are:

    BirthDate ServiceDate OrigAgeOnJan1 FixedAgeOnJan1
    ---------- ----------- ------------- --------------
    2000-01-01 2001-01-01 1     1
    2000-01-01 2001-07-01 1     1
    2000-04-01 2001-01-01 1     0
    2000-04-01 2001-07-01 1     0
    2000-01-01 2010-01-01 10    10
    2000-01-01 2010-07-01 10    10
    2000-04-01 2010-01-01 10    9
    2000-04-01 2010-07-01 10    9


    I haven't run any benchmarks, but I anticipate this calculation will be faster than anything involving DATEDIFF or DATEFROMPARTS.

  • dale_berta - Thursday, February 2, 2017 6:47 AM

    dale_berta - Tuesday, January 31, 2017 5:43 AM

    ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    I was wondering about that option. But I think birth date of January 1st is a special case. The "- 1" on the end may need to be in a CASE.

    I can confirm that birth date of Jan 1 needs to be handled. If you're born on Jan 1, then you're 1 year on on Jan 1 of the next year. If you're born anywhere from Jan 2 through Dec 31, you're 0 years (and x months and days) on Jan 1 of the next year.

    The original q states that "any date in yyya should be na", "any date in yyyb should be nb", etc., so it seemed clear to me that a Jan 1 birthday didn't actually matter.  In that case, it's a very simple calc to get the actual age, as given above.

    SQL DBA,SQL Server MVP(07, 08, 09) "It's a dog-eat-dog world, and I'm wearing Milk-Bone underwear." "Norm", on "Cheers". Also from "Cheers", from "Carla": "You need to know 3 things about Tortelli men: Tortelli men draw women like flies; Tortelli men treat women like flies; Tortelli men's brains are in their flies".

  • Jeff Moden - Wednesday, February 1, 2017 8:19 PM

    thomashohner - Tuesday, January 31, 2017 5:20 PM

    ScottPletcher - Monday, January 30, 2017 2:14 PM

    All you need is year, since any birthday during the @Service year won't count anyway:

    DECLARE @Birth DATETIME = '11/30/1951'
     ,@Service DATETIME = '2016-08-26'

    SELECT PeriodAge = YEAR(@Service) - YEAR(@Birth) - 1

    Hi Scott, I could have sworn i tried something similar when i first started and it did not work, however i removed the minus one and sure enough it met the rules so far in testing. I really feel like i took something simple and really over thought it. Thanks again !

    It depends... maybe it is a mistake.  If someone is born in December of 1951, are they 0 years old or 1 year old on 1952-01-01 according to your requirements.  Same question if they were born in January of 1951.

    My Apologies, its clear i did not proof read my initial post.
    The way CMS has it with examples

    Patients 18 years of age and older were born on or before December 31, 1997 = 18 +
    Patients born between January 1, 2007, and December 31, 2009  = 6 and 9 years of age 
    Patients born between January 1, 1952, and December 31, 1992 = 24 and 64 years of age
    Patients born on or before December 31, 2003, = 12 +

    I hope this clarifies. Again my appologies for a bad opening.

    ***SQL born on date Spring 2013:-)

Viewing 10 posts - 16 through 24 (of 24 total)

You must be logged in to reply to this topic. Login to reply