diff --git a/concepts/diagnosis/README.md b/concepts/diagnosis/README.md
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+The Clinical Classification Software (CCS) categorizes ICD-9 coded diagnoses into clinically meaningful groups. The categorization was developed by the Agency for Healthcare Research and Quality (AHRQ). More detail can be found on the AHRQ website: https://www.hcup-us.ahrq.gov/tools_software.jsp
+
+This folder contains:
+
+* `ccs_diagnosis_table.sql` - Creates two tables: `ccs_single_level_dx` and `ccs_multi_level_dx`. These two tables are loaded from `ccs_single_level_dx.csv.gz` and `ccs_multi_level_dx.csv.gz`. Note that the script assumes you are using PostgreSQL v9.4 or later, and you must execute the script from this directory.
diff --git a/concepts/diagnosis/ccs_diagnosis_table.sql b/concepts/diagnosis/ccs_diagnosis_table.sql
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+DROP TABLE IF EXISTS ccs_single_level_dx;
+CREATE TABLE ccs_single_level_dx
+(
+  ccs_id INT NOT NULL,
+  ccs_name VARCHAR(150) NOT NULL,
+  icd9_code CHAR(5) NOT NULL
+);
+
+\copy ccs_single_level_dx from program 'gzip -dc ccs_single_level.csv.gz' CSV HEADER;
+
+DROP TABLE IF EXISTS ccs_multi_level_dx;
+CREATE TABLE ccs_multi_level_dx
+(
+  ccs_mid VARCHAR(10) NOT NULL,
+  ccs_name VARCHAR(100) NOT NULL,
+  ccs_group1 VARCHAR(100),
+  ccs_group2 VARCHAR(100),
+  ccs_group3 VARCHAR(100),
+  icd9_code CHAR(5) NOT NULL
+);
+
+\copy ccs_multi_level_dx from program 'gzip -dc ccs_multi_level.csv.gz' CSV HEADER;
diff --git a/concepts/diagnosis/ccs_multi_level.csv.gz b/concepts/diagnosis/ccs_multi_level.csv.gz
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diff --git a/concepts/diagnosis/ccs_single_level.csv.gz b/concepts/diagnosis/ccs_single_level.csv.gz
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