Add SNPNE (SNP New Enrollee) scoring model support

Propagate institutional_snp_flag from core eligibility through the
CMS-HCC pipeline (stg_eligibility → int_members → int_demographic_factors).

SNP New Enrollees are now scored with SNPNE-specific coefficients
(risk_model_code = 'SNPNE') instead of regular NE coefficients.
The seed demographic_factors table needs 'SNP New' enrollment_status
rows populated with SNPNE coefficients from the CMS rate announcement.

SNPNE remains excluded from disease factors (demographic-only model).

Closes #1237

Author: chase-jones

models/cms_hcc/intermediate/cms_hcc__int_members.sql

@@ -26,6 +26,7 @@ with stg_eligibility as (
         , elig.dual_status_code
         , elig.medicare_status_code
         , elig.enrollment_status
+        , elig.institutional_snp_flag
         , dates.collection_year
         , dates.payment_year
         , dates.collection_start_date
@@ -141,6 +142,7 @@ with stg_eligibility as (
         , stg_eligibility.original_reason_entitlement_code
         , stg_eligibility.dual_status_code
         , stg_eligibility.medicare_status_code
+        , stg_eligibility.institutional_snp_flag
         /* Defaulting to "New" enrollment status when missing */
         , case
             when stg_eligibility.enrollment_status is not null then stg_eligibility.enrollment_status
@@ -185,6 +187,7 @@ with stg_eligibility as (
         , dual_status_code
         , medicare_status_code
         , enrollment_status
+        , institutional_snp_flag
         , enrollment_status_default
         , case
             when enrollment_status = 'New' and payment_year_age between 0 and 34 then '0-34'
@@ -231,6 +234,7 @@ with stg_eligibility as (
         , collection_start_date
         , collection_end_date
         , enrollment_status
+        , institutional_snp_flag
         , case
             when gender = 'female' then 'Female'
             when gender = 'male' then 'Male'
@@ -323,6 +327,7 @@ with stg_eligibility as (
         , cast(orec as {{ dbt.type_string() }}) as orec
         , cast(institutional_status as {{ dbt.type_string() }}) as institutional_status
         , cast(originally_disabled_flag as {{ dbt.type_string() }}) as originally_disabled_flag
+        , cast(institutional_snp_flag as {{ dbt.type_int() }}) as institutional_snp_flag
         {% if target.type == 'fabric' %}
             , cast(enrollment_status_default as bit) as enrollment_status_default
             , cast(medicaid_dual_status_default as bit) as medicaid_dual_status_default
@@ -352,6 +357,7 @@ select
     , orec
     , institutional_status
     , originally_disabled_flag
+    , institutional_snp_flag
     , enrollment_status_default
     , medicaid_dual_status_default
     , orec_default

models/cms_hcc/intermediate/factors/cms_hcc__int_demographic_factors.sql

@@ -16,6 +16,7 @@ with members as (
         , orec
         , originally_disabled_flag
         , institutional_status
+        , institutional_snp_flag
         , enrollment_status_default
         , medicaid_dual_status_default
         , orec_default
@@ -42,6 +43,8 @@ with members as (
         , case
             -- ESRD
             when enrollment_status = 'ESRD' then 'ESRD'
+            -- SNP New Enrollee
+            when enrollment_status = 'SNP New' then 'SNPNE'
             -- New Enrollee
             when enrollment_status = 'New' then 'E'
             -- Long Term Institutional (INS)
@@ -103,6 +106,49 @@ with members as (
                 else 'Aged'
             end = seed_demographic_factors.orec
     where members.enrollment_status = 'New'
+        and coalesce(members.institutional_snp_flag, 0) != 1
+)
+
+/*
+    SNP New Enrollees use SNPNE-specific coefficients from the seed
+    (enrollment_status = 'SNP New'). Same join structure as regular NE
+    but for members enrolled in a Special Needs Plan.
+*/
+, snpne_enrollees as (
+    select
+          members.person_id
+        , members.payer
+        , members.enrollment_status
+        , members.gender
+        , members.age_group
+        , members.medicaid_status
+        , members.dual_status
+        , members.orec
+        , members.originally_disabled_flag
+        , members.institutional_status
+        , members.enrollment_status_default
+        , members.medicaid_dual_status_default
+        , members.orec_default
+        , members.institutional_status_default
+        , members.payment_year
+        , members.collection_start_date
+        , members.collection_end_date
+        , seed_demographic_factors.model_version
+        , seed_demographic_factors.factor_type
+        , seed_demographic_factors.coefficient
+        , seed_demographic_factors.risk_model_code
+    from members
+    inner join seed_demographic_factors
+        on seed_demographic_factors.enrollment_status = 'SNP New'
+        and members.gender = seed_demographic_factors.gender
+        and members.age_group = seed_demographic_factors.age_group
+        and members.medicaid_status = seed_demographic_factors.medicaid_status
+        and case
+                when members.originally_disabled_flag = 'Yes' then 'Disabled'
+                else 'Aged'
+            end = seed_demographic_factors.orec
+    where members.enrollment_status = 'New'
+        and members.institutional_snp_flag = 1
 )
 
 , continuing_enrollees as (
@@ -175,6 +221,8 @@ with members as (
 , unioned as (
     select * from new_enrollees
     union all
+    select * from snpne_enrollees
+    union all
     select * from continuing_enrollees
     union all
     select * from institutional_enrollees

models/cms_hcc/staging/cms_hcc__stg_core__eligibility.sql

@@ -12,6 +12,7 @@ select distinct
     , dual_status_code
     , medicare_status_code
     , enrollment_status
+    , institutional_snp_flag
     , data_source
     , cast('{{ var('tuva_last_run') }}' as {{ dbt.type_timestamp() }}) as tuva_last_run
 from {{ ref('core__eligibility') }}