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Trimester Hierarchy

trimester_hierarchy.Rmd

Trimester Code Hierarchy

If multiple conflicting trimester codes occur on the same day, the trimester codes for that service day will be reassigned based on the logic below. However, the outcome codes will be preserved and unaffected. Trimester code “8” will only be used if no other code exist on the same day.

  1. Classify trimester codes into 4 tiers: tier 1 = 1, 2 or 3; tier 2 = 4 or 5; tier 3 = 9; tier 4 = 8;

    Trimester code 1 is assigned if a trimester code “1” exists and trimester codes “2”, “3”, “5” do not exist on the same service day

    Trimester code 2 is assigned if a trimester code “2” exists and trimester codes “1”, “3” do not exist on the same service day

    Trimester code 3 is assigned if a trimester code “3” exists and trimester codes “1”, “2” & “4” do not exist on the same service day

    Trimester code 4 is assigned if a trimester code “4” exists and trimester codes “1”, “2”, “3” & “5” do not exist on the same service day

    Trimester code 5 is assigned if a trimester code “5” exists and trimester codes “1”, “2”, “3” & “4” do not exist on the same service day

    Trimester code 9 is assigned if a trimester code “9” exists and trimester codes “1”, “2”, “3”, “4” & “5”, do not exist on the same service day

    Trimester code 8 is assigned if a trimester code “8” exists and trimester codes “1”, “2”, “3”, “4” “5” & “9”, do not exist on the same service day

  2. All other codes that incur on the same service day as the Z3AXX, P073X & P072X codes, which specify the number of gestation weeks, will be reassigned the trimester code of the Z3AXX code. If there are multiple Z3AXX/P073X/P072X codes occur on the same day, the code with the latest weeks specified will be used. Since codes ‘Z3A00’, ‘Z3A’, ‘Z3A0’, ‘Z3A01’, ‘Z3A1’, ‘Z3A2’, ‘Z3A3’ and ‘Z3A4’ do not specify the number of gestation weeks, they will not be included in this hierarchy.

  3. If patient has a Z3A code, use the weeks to calculate the correct trimester for those with conflicting before & after. 0 to 42 weeks is average term. 0-13 weeks = trimester 1, 14-27 weeks = trimester 2 and 28-42 weeks = trimester 3.

  4. Count the number of trimester codes group (i.e. #1s, #2s, etc) that are occurring on the same service day. If there are multiple codes for the same trimester and a few for a different trimester occurring on same day, use codes for the trimester assignment that has the most instances.

    Trimester code 1 is assigned if the # of trimester codes for “1” is greater than the # of trimester codes for “2” & “3” and greater than or equal to the # trimester codes for “4”, “5”

    Trimester code 2 is assigned if the # of trimester codes for “2” is greater than the # of trimester codes for “1” & “3” and greater than or equal to the # trimester codes for “4”, “5”

    Trimester code 3 is assigned if the # of trimester codes for “3” is greater than the # of trimester codes for “1” & “2” and greater than or equal to the # trimester codes for “4”, “5”

    Trimester code 4 is assigned if the # of trimester codes for “4” is greater than the # of trimester codes for “5” and trimester codes “1”, “2” & “3” do not exist on the same service day

    Trimester code 5 is assigned if the # of trimester codes for “5” is greater than the # of trimester codes for “4” and trimester codes “1”, “2” & “3” do not exist on the same service day

  5. Any Pregnancy loss: Ectopic pregnancy, Induced abortion, Spontaneous abortion, Stillbirth and Unclassified pregnancy loss

    Combinations:

  • If a spontaneous abortion code and a stillbirth code occur on the same day classify trimester coding as spontaneous abortion

  • If a spontaneous abortion code, a stillbirth code and an induced abortion code and/or an unclassified loss code occur on the same day classify trimester coding as spontaneous abortion

  • If an induced abortion code, a stillbirth code and no spontaneous abortion code occur on the same day classify trimester coding as induced abortion

  • If an induced abortion code, a stillbirth code, an unclassified loss code and no spontaneous abortion code occur on the same day classify trimester coding as induced abortion

  • If an Any Pregnancy loss code occurs on the same day as a labor or delivery code (L and D list) follow Any Pregnancy loss code trimester coding

    Of the above combinations, if multiple conflicting pregnancy loss trimester codes appear on the same service date, select the highest trimester code and the lowest tier ranking (i.e. tier 1 = 1,2 or 3; tier 2 = 4 or 5; tier 3 = 9; tier 4 = 8)

  1. Primary and Secondary diagnosis will be identified. If the trimester assignment for the code in the secondary position does not match code in primary position, use primary trimester assignment. If multiple still exist, count the number of primary dx trimester codes group (i.e. #1s, #2s, etc) that are occurring on the same service day in repeat assignment logic used in Hierarchy #1 using count of primary only

  2. Instances where there is a trimester code of “1”, outcome = “Delivery” and no outcomes of “Induced abortion” or “Spontaneous abortion”, then the trimester code will be reassigned a “5”

  3. Claims data files “Inpatient” & “Outpatient” will be identified. If the trimester assignment for the code on the outpatient file does not match code on the inpatient file, use inpatient trimester assignment. If multiple still exist, count the number of inpatient trimester codes group (i.e. #1s, #2s, etc) that are occurring on the same service day in repeat assignment logic used in Hierarchy #1 using count of inpatient only

  4. Of remaining service day claims with conflicting trimester assignment, if additional claims exist for these patients within 60 days, ignore and do not include them to assign the trimester

  5. If patients have an ultrasound CPT code of (‘76801’ ‘76802’) for a first trimester, conflicting codes that incur on the same service day will be reassigned the CPT trimester code of 1

  6. Reassign the trimesters based on the following scenarios:

    Trimester code 2 is assigned if a trimester code “1”, “2” & “5” exists and trimester codes “3” & “4” do not exist on the same service day

    Trimester code 3 is assigned if a trimester code “3” & “8” exists and trimester code “4” do not exist on the same service day

    Trimester code 3 is assigned if a trimester code “1”, “3” & “5” exists and trimester code “4” do not exist on the same service day

    Trimester code 4 is assigned if a trimester code “1” & “2” exists and trimester codes “3” & “5” do not exist on the same service day

    Trimester code 5 is assigned if a trimester code “2” & “3” exists and trimester codes “1” & “8” do not exist on the same service day

    Trimester code 5 is assigned if a trimester code “3”, “4” & “5” exists and trimester codes “1” & “2” do not exist on the same service day

  7. Of remaining service day claims with conflicting trimester assignment, ignore and do not include them to assign the trimester