Supplementary Appendix

Transcription

1 Supplementary Appendix This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Krumholz HM, Wang K, Lin Z, et al. Hospital-readmission risk isolating hospital effects from patient effects. N Engl J Med 2017;377: DOI: /NEJMsa

2 Supplemental Appendix Table of Contents Table of Contents 1 List of Investigators 2 Figure S1. Histogram of differences in top-50 principal discharge diagnoses (ICD-9-CM Diagnosis Code) for each quartile pair... 3 Table S1. Comparison of those included and excluded from the study sample (in the second random half).. 4 Table S2. Hierarchical logistic regression model risk factor model coefficients. 5 Table S3. Mean risk-standardized readmission rates in each quartile of the performance specification sample 20 Table S4. 30-day readmission rate by hospital sequence.. 21 Table S5. Top-50 ICD-9-CM diagnosis codes in 6 quartile pairs.. 22 Table S6. Admission characteristics for each quartile pair 34 Reference

3 List of Investigators Harlan M. Krumholz, MD, SM Kun Wang, PhD Zhenqiu Lin, PhD Kumar Dharmarajan, MD, MBA Leora I. Horwitz, MD, MHS Joseph S. Ross, MD, MHS Elizabeth E. Drye, MD, SM Susannah M. Bernheim, MD, MHS Sharon-Lise T. Normand, PhD 2

4 Figure S1. Histogram of differences in top-50 principal discharge diagnoses (ICD-9-CM Diagnosis Code) for each quartile pair. 3

5 Table S1. Comparison of those included and excluded from the study sample (in the second random half). Study Cohort, N (%) Exclusions, N (%) No. of hospitalizations 132,283 3,322,887 No. of patients 59,983 2,706,374 No. of hospitals 4,442 4,734 Age Mean (SD) 77.5 (8.05) 78.4 (8.36) Median (IQR) 77 (71-84) 78 (71-85) Race White 106,586 (80.6) 2,854,188 (85.9) Non-White 25,697 (19.4) 468,699 (14.1) Gender Male 58,512 (44.2) 1,448,838 (43.6) Female 73,771 (55.8) 1,874,049 (56.4) Dual eligibility No 114,469 (86.5) 3,004,742 (90.4) Yes 17,814 (13.5) 318,145 (9.6) Low socioeconomic status No 98,386 (74.7) 2,630,064 (79.5) Yes 33,286 (25.3) 677,821 (20.5) Region of country Midwest 31,727 (24.0) 803,716 (24.2) Northeast 24,314 (18.4) 641,061 (19.3) South 55,528 (42.0) 1,347,971 (40.6) West 19,883 (15.0) 512,703 (15.4) Other 831 (0.6) 17,436 (0.5) IQR, interquartile range; SD, standard deviation Dual eligible beneficiaries were defined as individuals enrolled in both Medicaid and Medicare; beneficiaries with low socioeconomic status were defined as those in the lowest quartile group of the Agency for Healthcare Research and Quality socioeconomic status index score, a composite measure of socioeconomic status that was calculated based on 7 measures from the census data. 1 4

6 Table S2. Hierarchical logistic regression model risk factor model coefficients. Medicine specialty cohort Risk variable Estimate SE Age minus 65 (years above 65, continuous) 0 0 Metastatic cancer or acute leukemia (CC 7) Severe cancer (CC 8-9) Other cancers (CC 10-12) Severe hematological disorders (CC 44) Coagulation defects and other specified hematological disorders (CC 46) Iron deficiency or other unspecified anemias and blood disease (CC 47) End-stage liver disease; cirrhosis of liver (CC 25-26) Pancreatic disease (CC 32) Dialysis status (CC 130) Renal failure (CC 131) Transplants (CC 128, 174) Severe infection (CC 1, 3-5) Other infectious diseases and pneumonias (CC 6, ) Septicemia/shock (CC 2) Congestive heart failure (CC 80) Coronary atherosclerosis or angina, cerebrovascular disease (CC 81-84, 89, 98-99, ) Specified arrhythmias and other heart rhythm disorders (CC 92-93) Cardio-respiratory failure and shock (CC 79) Chronic obstructive pulmonary disease (COPD) (CC 108) Fibrosis of lung or other chronic lung disorders (CC 109) Protein-calorie malnutrition (CC 21) Disorders of fluid/electrolyte/acid-base (CC 22-23) Rheumatoid arthritis and inflammatory connective tissue disease (CC 38)

7 Diabetes mellitus (DM) or DM complications (CC 15-19, ) Decubitus ulcer or chronic skin ulcer (CC ) Hemiplegia, paraplegia, paralysis, functional disability (CC 67-69, , ) Seizure disorders and convulsions (CC 74) Respirator dependence/tracheostomy status (CC 77) Drug/alcohol psychosis or dependence (CC 51-52) Psychiatric comorbidity (CC 54-56, 58, 60) Hip fracture/dislocation (CC 158) Low frequency conditions Phlebitis; thrombophlebitis and thromboembolism (CCS 118) Hemorrhoids (CCS 120) Other diseases of veins and lymphatics (CCS 121) Influenza (CCS 123) Other upper respiratory infections (CCS 126) Aspiration pneumonitis; food/vomitus (CCS 129) Pleurisy; pneumothorax; pulmonary collapse (CCS 130) Lung disease due to external agents (CCS 132) Other lower respiratory disease (CCS 133) Other upper respiratory disease (CCS 134) Intestinal infection (CCS 135) Disorders of teeth and jaw (CCS 136) Diseases of mouth; excluding dental (CCS 137) Esophageal disorders (CCS 138) Gastroduodenal ulcer (except hemorrhage) (CCS 139) Gastritis and duodenitis (CCS 140) Other disorders of stomach and duodenum (CCS 141) Appendicitis and other appendiceal conditions (CCS 142) Abdominal hernia (CCS 143) Regional enteritis and ulcerative colitis (CCS 144)

8 Intestinal obstruction without hernia (CCS 145) Diverticulosis and diverticulitis (CCS 146) Anal and rectal conditions (CCS 147) Peritonitis and intestinal abscess (CCS 148) Biliary tract disease (CCS 149) Other liver diseases (CCS 151) Pancreatic disorders (not diabetes) (CCS 152) Gastrointestinal hemorrhage (CCS 153) Noninfectious gastroenteritis (CCS 154) Other gastrointestinal disorders (CCS 155) Nephritis; nephrosis; renal sclerosis (CCS 156) Acute and unspecified renal failure (CCS 157) Chronic kidney disease (CCS 158) Urinary tract infections (CCS 159) Calculus of urinary tract (CCS 160) Other diseases of kidney and ureters (CCS 161) Other diseases of bladder and urethra (CCS 162) Genitourinary symptoms and ill-defined conditions (CCS 163) Hyperplasia of prostate (CCS 164) Inflammatory conditions of male genital organs (CCS 165) Skin and subcutaneous tissue infections (CCS 197) Other inflammatory condition of skin (CCS 198) Chronic ulcer of skin (CCS 199) Septicemia (except in labor) (CCS 2) Infective arthritis and osteomyelitis (except that caused by tuberculosis or sexually transmitted disease) (CCS 201) Rheumatoid arthritis and related disease (CCS 202) Osteoarthritis (CCS 203) Other non-traumatic joint disorders (CCS 204)

9 Spondylosis; intervertebral disc disorders; other back problems (CCS 205) Pathological fracture (CCS 207) Other connective tissue disease (CCS 211) Other bone disease and musculoskeletal deformities (CCS 212) Fracture of neck of femur (hip) (CCS 226) Skull and face fractures (CCS 228) Fracture of upper limb (CCS 229) Fracture of lower limb (CCS 230) Other fractures (CCS 231) Sprains and strains (CCS 232) Crushing injury or internal injury (CCS 234) Open wounds of head; neck; and trunk (CCS 235) Open wounds of extremities (CCS 236) Complication of device; implant or graft (CCS 237) Complications of surgical procedures or medical care (CCS 238) Superficial injury; contusion (CCS 239) Burns (CCS 240) Poisoning by psychotropic agents (CCS 241) Poisoning by other medications and drugs (CCS 242) Poisoning by nonmedicinal substances (CCS 243) Other injuries and conditions due to external causes (CCS 244) Syncope (CCS 245) Fever of unknown origin (CCS 246) Gangrene (CCS 248) Nausea and vomiting (CCS 250) Abdominal pain (CCS 251) Malaise and fatigue (CCS 252) Allergic reactions (CCS 253) Residual codes; unclassified (CCS 259)

10 Mycoses (CCS 4) Other and unspecified benign neoplasm (CCS 47) Thyroid disorders (CCS 48) Diabetes mellitus without complication (CCS 49) Diabetes mellitus with complications (CCS 50) Other endocrine disorders (CCS 51) Nutritional deficiencies (CCS 52) Gout and other crystal arthropathies (CCS 54) Fluid and electrolyte disorders (CCS 55) Other nutritional; endocrine; and metabolic disorders (CCS 58) Deficiency and other anemia (CCS 59) Hepatitis (CCS 6) Acute posthemorrhagic anemia (CCS 60) Coagulation and hemorrhagic disorders (CCS 62) Diseases of white blood cells (CCS 63) Delirium, dementia, and amnestic and other cognitive disorders (CCS 653) Alcohol-related disorders (CCS 660) Substance-related disorders (CCS 661) Viral infection (CCS 7) Meningitis (except that caused by tuberculosis or sexually transmitted disease) (CCS 76) Encephalitis (except that caused by tuberculosis or sexually transmitted disease) (CCS 77) Other infections; including parasitic (CCS 8) Headache; including migraine (CCS 84) Blindness and vision defects (CCS 89) Inflammation; infection of eye (except that caused by tuberculosis or sexually transmitted disease) (CCS 90) Other eye disorders (CCS 91) Conditions associated with dizziness or vertigo (CCS 93) Essential hypertension (CCS 98)

11 Hypertension with complications and secondary hypertension (CCS 99) Reference Reference Cardiorespiratory specialty cohort Risk variable Estimate SE Age minus 65 (years above 65, continuous) Metastatic cancer or acute leukemia (CC 7) Severe cancer (CC 8-9) Other cancers (CC 10-12) Severe hematological disorders (CC 44) Coagulation defects and other specified hematological disorders (CC 46) Iron deficiency or other unspecified anemias and blood disease (CC 47) End-stage liver disease; cirrhosis of liver (CC 25-26) Pancreatic disease (CC 32) Dialysis status (CC 130) Renal failure (CC 131) Transplants (CC 128, 174) Severe infection (CC 1, 3-5) Other infectious diseases and pneumonias (CC 6, ) Septicemia/shock (CC 2) Congestive heart failure (CC 80) Coronary atherosclerosis or angina, cerebrovascular disease (CC 81-84, 89, 98-99, ) Specified arrhythmias and other heart rhythm disorders (CC 92-93) Cardio-respiratory failure and shock (CC 79) Chronic obstructive pulmonary disease (COPD) (CC 108) Fibrosis of lung or other chronic lung disorders (CC 109) Protein-calorie malnutrition (CC 21) Disorders of fluid/electrolyte/acid-base (CC 22-23) Rheumatoid arthritis and inflammatory connective tissue disease (CC 38) Diabetes mellitus (DM) or DM complications (CC 15-19, ) Decubitus ulcer or chronic skin ulcer (CC )

12 Hemiplegia, paraplegia, paralysis, functional disability (CC 67-69, , ) Seizure disorders and convulsions (CC 74) Respirator dependence/tracheostomy status (CC 77) Drug/alcohol psychosis or dependence (CC 51-52) Psychiatric comorbidity (CC 54-56, 58, 60) Hip fracture/dislocation (CC 158) Low frequency conditions Pulmonary heart disease (CCS 103) Congestive heart failure; nonhypertensive (CCS 108) Pneumonia (except that caused by tuberculosis or sexually transmitted disease) (CCS 122) Acute bronchitis (CCS 125) Chronic obstructive pulmonary disease and bronchiectasis (CCS 127) Asthma (CCS 128) Respiratory failure; insufficiency; arrest (adult) (CCS 131) Reference Reference Surgical specialty cohort Risk variable Estimate SE Age minus 65 (years above 65, continuous) Metastatic cancer or acute leukemia (CC 7) Severe cancer (CC 8-9) Other cancers (CC 10-12) Severe hematological disorders (CC 44) Coagulation defects and other specified hematological disorders (CC 46) Iron deficiency or other unspecified anemias and blood disease (CC 47) End-stage liver disease; cirrhosis of liver (CC 25-26) Pancreatic disease (CC 32) Dialysis status (CC 130) Renal failure (CC 131) Transplants (CC 128, 174) Severe infection (CC 1, 3-5)

13 Other infectious diseases and pneumonias (CC 6, ) Septicemia/shock (CC 2) Congestive heart failure (CC 80) Coronary atherosclerosis or angina, cerebrovascular disease (CC 81-84, 89, 98-99, ) Specified arrhythmias and other heart rhythm disorders (CC 92-93) Cardio-respiratory failure and shock (CC 79) Chronic obstructive pulmonary disease (COPD) (CC 108) Fibrosis of lung or other chronic lung disorders (CC 109) Protein-calorie malnutrition (CC 21) Disorders of fluid/electrolyte/acid-base (CC 22-23) Rheumatoid arthritis and inflammatory connective tissue disease (CC 38) Diabetes mellitus (DM) or DM complications (CC 15-19, ) Decubitus ulcer or chronic skin ulcer (CC ) Hemiplegia, paraplegia, paralysis, functional disability (CC 67-69, , ) Seizure disorders and convulsions (CC 74) Respirator dependence/tracheostomy status (CC 77) Drug/alcohol psychosis or dependence (CC 51-52) Psychiatric comorbidity (CC 54-56, 58, 60) Hip fracture/dislocation (CC 158) Low frequency conditions Acute myocardial infarction (CCS 100) Coronary atherosclerosis and other heart disease (CCS 101) Cardiac dysrhythmias (CCS 106) Congestive heart failure; nonhypertensive (CCS 108) Acute cerebrovascular disease (CCS 109) Cancer of head and neck (CCS 11) Occlusion or stenosis of precerebral arteries (CCS 110) Other and ill-defined cerebrovascular disease (CCS 111) Peripheral and visceral atherosclerosis (CCS 114)

14 Aortic; peripheral; and visceral artery aneurysms (CCS 115) Aortic and peripheral arterial embolism or thrombosis (CCS 116) Other circulatory disease (CCS 117) Cancer of esophagus (CCS 12) Pneumonia (except that caused by tuberculosis or sexually transmitted disease) (CCS 122) Chronic obstructive pulmonary disease and bronchiectasis (CCS 127) Cancer of stomach (CCS 13) Pleurisy; pneumothorax; pulmonary collapse (CCS 130) Respiratory failure; insufficiency; arrest (adult) (CCS 131) Other lower respiratory disease (CCS 133) Other upper respiratory disease (CCS 134) Esophageal disorders (CCS 138) Gastroduodenal ulcer (except hemorrhage) (CCS 139) Cancer of colon (CCS 14) Other disorders of stomach and duodenum (CCS 141) Appendicitis and other appendiceal conditions (CCS 142) Abdominal hernia (CCS 143) Regional enteritis and ulcerative colitis (CCS 144) Intestinal obstruction without hernia (CCS 145) Diverticulosis and diverticulitis (CCS 146) Anal and rectal conditions (CCS 147) Biliary tract disease (CCS 149) Cancer of rectum and anus (CCS 15) Other liver diseases (CCS 151) Pancreatic disorders (not diabetes) (CCS 152) Gastrointestinal hemorrhage (CCS 153) Other gastrointestinal disorders (CCS 155) Acute and unspecified renal failure (CCS 157) Urinary tract infections (CCS 159)

15 Cancer of liver and intrahepatic bile duct (CCS 16) Calculus of urinary tract (CCS 160) Other diseases of kidney and ureters (CCS 161) Other diseases of bladder and urethra (CCS 162) Genitourinary symptoms and ill-defined conditions (CCS 163) Hyperplasia of prostate (CCS 164) Cancer of pancreas (CCS 17) Prolapse of female genital organs (CCS 170) Other female genital disorders (CCS 175) Cancer of other GI organs; peritoneum (CCS 18) Cancer of bronchus; lung (CCS 19) Skin and subcutaneous tissue infections (CCS 197) Chronic ulcer of skin (CCS 199) Septicemia (except in labor) (CCS 2) Infective arthritis and osteomyelitis (except that caused by tuberculosis or sexually transmitted disease) (CCS 201) Rheumatoid arthritis and related disease (CCS 202) Osteoarthritis (CCS 203) Other non-traumatic joint disorders (CCS 204) Spondylosis; intervertebral disc disorders; other back problems (CCS 205) Pathological fracture (CCS 207) Other acquired deformities (CCS 209) Cancer of bone and connective tissue (CCS 21) Other connective tissue disease (CCS 211) Other bone disease and musculoskeletal deformities (CCS 212) Cardiac and circulatory congenital anomalies (CCS 213) Other congenital anomalies (CCS 217) Joint disorders and dislocations; trauma-related (CCS 225) Fracture of neck of femur (hip) (CCS 226)

16 Spinal cord injury (CCS 227) Skull and face fractures (CCS 228) Fracture of upper limb (CCS 229) Other non-epithelial cancer of skin (CCS 23) Fracture of lower limb (CCS 230) Other fractures (CCS 231) Sprains and strains (CCS 232) Intracranial injury (CCS 233) Crushing injury or internal injury (CCS 234) Open wounds of extremities (CCS 236) Complication of device; implant or graft (CCS 237) Complications of surgical procedures or medical care (CCS 238) Cancer of breast (CCS 24) Burns (CCS 240) Gangrene (CCS 248) Cancer of uterus (CCS 25) Other aftercare (CCS 257) Cancer of ovary (CCS 27) Cancer of other female genital organs (CCS 28) Cancer of prostate (CCS 29) Cancer of bladder (CCS 32) Cancer of kidney and renal pelvis (CCS 33) Cancer of other urinary organs (CCS 34) Cancer of brain and nervous system (CCS 35) Cancer of thyroid (CCS 36) Non-Hodgkin s lymphoma (CCS 38) Secondary malignancies (CCS 42) Neoplasms of unspecified nature or uncertain behavior (CCS 44) Other and unspecified benign neoplasm (CCS 47)

17 Thyroid disorders (CCS 48) Diabetes mellitus with complications (CCS 50) Other endocrine disorders (CCS 51) Fluid and electrolyte disorders (CCS 55) Other nutritional; endocrine; and metabolic disorders (CCS 58) Parkinson s disease (CCS 79) Other hereditary and degenerative nervous system conditions (CCS 81) Other nervous system disorders (CCS 95) Heart valve disorders (CCS 96) Peri-; endo-; and myocarditis; cardiomyopathy (except that caused by tuberculosis or sexually transmitted disease) (CCS 97) Hypertension with complications and secondary hypertension (CCS 99) Reference Reference Cardiovascular specialty cohort Risk variable Estimate SE Age minus 65 (years above 65, continuous) Metastatic cancer or acute leukemia (CC 7) Severe cancer (CC 8-9) Other cancers (CC 10-12) Severe hematological disorders (CC 44) Coagulation defects and other specified hematological disorders (CC 46) Iron deficiency or other unspecified anemias and blood disease (CC 47) End-stage liver disease; cirrhosis of liver (CC 25-26) Pancreatic disease (CC 32) Dialysis status (CC 130) Renal failure (CC 131) Transplants (CC 128, 174) Severe infection (CC 1, 3-5) Other infectious diseases and pneumonias (CC 6, ) Septicemia/shock (CC 2)

18 Congestive heart failure (CC 80) Coronary atherosclerosis or angina, cerebrovascular disease (CC 81-84, 89, 98-99, ) Specified arrhythmias and other heart rhythm disorders (CC 92-93) Cardio-respiratory failure and shock (CC 79) Chronic obstructive pulmonary disease (COPD) (CC 108) Fibrosis of lung or other chronic lung disorders (CC 109) Protein-calorie malnutrition (CC 21) Disorders of fluid/electrolyte/acid-base (CC 22-23) Rheumatoid arthritis and inflammatory connective tissue disease (CC 38) Diabetes mellitus (DM) or DM complications (CC 15-19, ) Decubitus ulcer or chronic skin ulcer (CC ) Hemiplegia, paraplegia, paralysis, functional disability (CC 67-69, , ) Seizure disorders and convulsions (CC 74) Respirator dependence/tracheostomy status (CC 77) Drug/alcohol psychosis or dependence (CC 51-52) Psychiatric comorbidity (CC 54-56, 58, 60) Hip fracture/dislocation (CC 158) Low frequency conditions Acute myocardial infarction (CCS 100) Coronary atherosclerosis and other heart disease (CCS 101) Nonspecific chest pain (CCS 102) Other and ill-defined heart disease (CCS 104) Conduction disorders (CCS 105) Cardiac dysrhythmias (CCS 106) Cardiac arrest and ventricular fibrillation (CCS 107) Peripheral and visceral atherosclerosis (CCS 114) Aortic; peripheral; and visceral artery aneurysms (CCS 115) Aortic and peripheral arterial embolism or thrombosis (CCS 116) Other circulatory disease (CCS 117)

19 Heart valve disorders (CCS 96) Peri-; endo-; and myocarditis; cardiomyopathy (except that caused by tuberculosis or sexually transmitted disease) (CCS 97) Neurology specialty cohort Reference Risk variable Estimate SE Reference Age minus 65 (years above 65, continuous) Metastatic cancer or acute leukemia (CC 7) Severe cancer (CC 8-9) Other cancers (CC 10-12) Severe hematological disorders (CC 44) Coagulation defects and other specified hematological disorders (CC 46) Iron deficiency or other unspecified anemias and blood disease (CC 47) End-stage liver disease; cirrhosis of liver (CC 25-26) Pancreatic disease (CC 32) Dialysis status (CC 130) Renal failure (CC 131) Transplants (CC 128, 174) Severe infection (CC 1, 3-5) Other infectious diseases and pneumonias (CC 6, ) Septicemia/shock (CC 2) Congestive heart failure (CC 80) Coronary atherosclerosis or angina, cerebrovascular disease (CC 81-84, 89, 98-99, ) Specified arrhythmias and other heart rhythm disorders (CC 92-93) Cardio-respiratory failure and shock (CC 79) Chronic obstructive pulmonary disease (COPD) (CC 108) Fibrosis of lung or other chronic lung disorders (CC 109) Protein-calorie malnutrition (CC 21) Disorders of fluid/electrolyte/acid-base (CC 22-23) Rheumatoid arthritis and inflammatory connective tissue disease (CC 38)

20 Diabetes mellitus (DM) or DM complications (CC 15-19, ) Decubitus ulcer or chronic skin ulcer (CC ) Hemiplegia, paraplegia, paralysis, functional disability (CC 67-69, , ) Seizure disorders and convulsions (CC 74) Respirator dependence/tracheostomy status (CC 77) Drug/alcohol psychosis or dependence (CC 51-52) Psychiatric comorbidity (CC 54-56, 58, 60) Hip fracture/dislocation (CC 158) Low frequency conditions Acute cerebrovascular disease (CCS 109) Occlusion or stenosis of precerebral arteries (CCS 110) Other and ill-defined cerebrovascular disease (CCS 111) Transient cerebral ischemia (CCS 112) Late effects of cerebrovascular disease (CCS 113) Intracranial injury (CCS 233) Parkinson s disease (CCS 79) Multiple sclerosis (CCS 80) Other hereditary and degenerative nervous system conditions (CCS 81) Epilepsy; convulsions (CCS 83) Coma; stupor; and brain damage (CCS 85) Other nervous system disorders (CCS 95) Reference Reference SE, standard error 19

21 Table S3. Mean risk-standardized readmission rates in each quartile of the performance specification sample. Performance specification sample No. of hospitals Mean, % (SD) Min, Max (%) Median, % (IQR, %) Q (0.4) (11.7,15.3) 15.1 ( ) Q (0.1) (15.3,15.5) 15.4 ( ) Q (0.1) (15.5,15.8) 15.7 ( ) Q (0.4) (15.8,19.6) 16.2 ( ) Overall (0.6) (11.7,19.6) 15.5 ( ) IQR, interquartile range; SD, standard deviation 20

22 Table S4. 30-day readmission rate by hospital sequence. Quartile pairs Q1 vs. Q2 Q2 vs. Q3 Q3 vs. Q4 Q1 vs. Q3 Q2 vs. Q4 Q1 vs. Q4 Hospital sequence Number of admissions % Lower quartile 30-day readmission rate, % Higher quartile Difference in readmission rate Q1_Q Q2_Q Q2_Q Q3_Q Q3_Q Q4_Q Q1_Q Q3_Q Q2_Q Q4_Q Q1_Q Q4_Q SE Q1_Q2: patients admitted first to Q1 and next to Q2 SE = standard error 21

23 Q1 Table S5. Top-50 ICD-9-CM diagnosis codes in 6 quartile pairs. ICD-9-CM Count % ICD-9-CM Count % Unspecified septicemia Unspecified septicemia Orthopedic aftercare NEC (Other orthopedic aftercare) Urinary tract infection NOS (Urinary tract infection, site not specified) Urinary tract infection NOS (Urinary tract infection, site not specified) Orthopedic aftercare NEC (Other orthopedic aftercare) Obstructive chronic bronchitis with (acute) exacerbation Obstructive chronic bronchitis with (acute) exacerbation Pneumonia, organism unspecified Pneumonia, organism unspecified Acute on chronic systolic heart failure Acute on chronic systolic heart failure Acute on chronic diastolic heart failure Cellulitis and abscess of leg, except foot Acute and chronic respiratory failure Acute on chronic diastolic heart failure Cellulitis and abscess of leg, except foot Atrial fibrillation Atrial fibrillation Acute and chronic respiratory failure Subendocardial infarction, initial episode of care Subendocardial infarction, initial episode of care Osteoarthrosis, localized, not specified whether primary or secondary, Osteoarthrosis, localized, not specified whether primary or lower leg secondary, lower leg Pneumonitis due to inhalation of food or vomitus Congestive heart failure, unspecified Acute on chronic combined systolic and diastolic heart failure Pneumonitis due to inhalation of food or vomitus Acute respiratory failure Hemorrhage of gastrointestinal tract, unspecified Unspecified intestinal obstruction 57 1 Unspecified intestinal obstruction Hemorrhage of gastrointestinal tract, unspecified 56 1 Intestinal infection due to clostridium difficile 58 1 Intestinal infection due to clostridium difficile 54 1 Acute respiratory failure 57 1 Infection and inflammatory reaction due to indwelling urinary catheter 54 1 Coronary atherosclerosis of native coronary artery Resection of vessel with replacement, other vessels of head and neck Dehydration Obstructive chronic bronchitis with acute bronchitis Acute on chronic combined systolic and diastolic heart failure Coronary atherosclerosis of native coronary artery Hyposmolality and/or hyponatremia Cerebral artery occlusion, unspecified with cerebral infarction Cerebral artery occlusion, unspecified with cerebral infarction Hyposmolality and/or hyponatremia Acute pancreatitis Q2 22

24 Diverticulitis of colon (without mention of hemorrhage) Infection and inflammatory reaction due to indwelling urinary catheter Diabetes with other specified manifestations, type II or unspecified Diabetes with other specified manifestations, type II or type, not stated as uncontrolled unspecified type, not stated as uncontrolled Congestive heart failure, unspecified Diverticulitis of colon (without mention of hemorrhage) Streptococcal septicemia Resection of vessel with replacement, other vessels of head and neck Osteoarthrosis, localized, not specified whether primary or secondary, Obstructive chronic bronchitis with acute bronchitis pelvic region and thigh Syncope and collapse Syncope and collapse Other postoperative infection Diverticulosis of colon with hemorrhage Closed fracture of intertrochanteric section of neck of femur Closed fracture of unspecified part of neck of femur Chronic obstructive asthma with (acute) exacerbation Infection and inflammatory reaction due to internal joint prosthesis Acute pancreatitis Closed fracture of intertrochanteric section of neck of femur Hepatic encephalopathy Anemia, unspecified Blood in stool Blood in stool Diverticulosis of colon with hemorrhage Streptococcal septicemia Other septicemia due to gram-negative organisms Chronic obstructive asthma with (acute) exacerbation Other and unspecified noninfectious gastroenteritis and colitis Osteoarthrosis, localized, not specified whether primary or secondary, pelvic region and thigh Dehydration Acute posthemorrhagic anemia Occlusion and stenosis of carotid artery without mention of cerebral Aortic valve disorders infarction Infection and inflammatory reaction due to internal joint prosthesis Other and unspecified noninfectious gastroenteritis and colitis Unspecified pleural effusion Hepatic encephalopathy Hypertensive heart and chronic kidney disease, unspecified, with heart Osteoarthrosis, localized, primary, lower leg failure and with chronic kidney disease stage I through stage IV, or unspecified Acute diastolic heart failure Other septicemia due to gram-negative organisms Intestinal or peritoneal adhesions with obstruction (postoperative) Other postoperative infection (postinfection) Acute kidney failure with lesion of tubular necrosis Hyperpotassemia

25 Pyelonephritis, unspecified Hypertensive heart and chronic kidney disease, unspecified, with heart failure and with chronic kidney disease stage I through stage IV, or unspecified Other complications due to renal dialysis device, implant, and graft Other chest pain Anemia, unspecified Acute diastolic heart failure Q2 ICD-9-CM Count % ICD-9-CM Count % Unspecified septicemia Unspecified septicemia Urinary tract infection NOS (Urinary tract infection, site not specified) Obstructive chronic bronchitis with (acute) exacerbation Orthopedic aftercare NEC (Other orthopedic aftercare) Orthopedic aftercare NEC (Other orthopedic aftercare) Obstructive chronic bronchitis with (acute) exacerbation Urinary tract infection NOS (Urinary tract infection, site not specified) Pneumonia, organism unspecified Pneumonia, organism unspecified Acute on chronic systolic heart failure Acute on chronic systolic heart failure Acute on chronic diastolic heart failure Acute on chronic diastolic heart failure Atrial fibrillation Pneumonitis due to inhalation of food or vomitus Acute and chronic respiratory failure Acute and chronic respiratory failure Cellulitis and abscess of leg, except foot Atrial fibrillation Congestive heart failure, unspecified Hemorrhage of gastrointestinal tract, unspecified Pneumonitis due to inhalation of food or vomitus Congestive heart failure, unspecified Acute respiratory failure Cellulitis and abscess of leg, except foot Hemorrhage of gastrointestinal tract, unspecified Hyposmolality and/or hyponatremia Obstructive chronic bronchitis with acute bronchitis 36 1 Acute on chronic combined systolic and diastolic heart failure 34 1 Acute on chronic combined systolic and diastolic heart failure 33 1 Resection of vessel with replacement, other vessels of head 33 1 and neck Intestinal infection due to clostridium difficile Subendocardial infarction, initial episode of care 33 1 Osteoarthrosis, localized, not specified whether primary or secondary, Intestinal infection due to clostridium difficile lower leg Subendocardial infarction, initial episode of care Diabetes with other specified manifestations, type II or unspecified type, not stated as uncontrolled Infection and inflammatory reaction due to indwelling urinary catheter Obstructive chronic bronchitis with acute bronchitis Unspecified intestinal obstruction Acute respiratory failure Cerebral artery occlusion, unspecified with cerebral infarction Cerebral artery occlusion, unspecified with cerebral infarction Q

26 Coronary atherosclerosis of native coronary artery Unspecified intestinal obstruction Dehydration Hepatic encephalopathy Resection of vessel with replacement, other vessels of head and neck Osteoarthrosis, localized, not specified whether primary or secondary, lower leg Diabetes with other specified manifestations, type II or unspecified Chronic obstructive asthma with (acute) exacerbation type, not stated as uncontrolled Other and unspecified noninfectious gastroenteritis and colitis Diverticulitis of colon (without mention of hemorrhage) Acute pancreatitis Acute pancreatitis Hyposmolality and/or hyponatremia Syncope and collapse Hyperpotassemia Blood in stool Chronic obstructive asthma with (acute) exacerbation Infection and inflammatory reaction due to indwelling urinary catheter Diverticulosis of colon with hemorrhage Dehydration Altered mental status Anemia, unspecified Streptococcal septicemia Unspecified transient cerebral ischemia Anemia, unspecified Closed fracture of unspecified part of neck of femur Diverticulitis of colon (without mention of hemorrhage) Aortic valve disorders Osteoarthrosis, localized, not specified whether primary or secondary, Acute diastolic heart failure pelvic region and thigh Closed fracture of intertrochanteric section of neck of femur Other and unspecified noninfectious gastroenteritis and colitis Pneumonitis due to inhalation of food or vomitus Streptococcal septicemia Other pulmonary embolism and infarction Coronary atherosclerosis of native coronary artery Syncope and collapse Influenza with pneumonia Other postoperative infection Osteoarthrosis, localized, not specified whether primary or secondary, pelvic region and thigh Other specified cardiac dysrhythmias Altered mental status Unspecified pleural effusion Other postoperative infection Hepatic encephalopathy Hypertensive heart and chronic kidney disease, unspecified, with heart failure and with chronic kidney disease stage I through stage IV, or unspecified Other chest pain Other specified cardiac dysrhythmias Other fluid overload Cellulitis and abscess of foot, except toes Acute venous embolism and thrombosis of deep vessels of proximal Infection and inflammatory reaction due to internal joint lower extremity prosthesis Blood in stool Other septicemia due to gram-negative organisms

27 Infection and inflammatory reaction due to internal joint prosthesis Diverticulosis of colon with hemorrhage Q3 ICD-9-CM Count % ICD-9-CM Count % Unspecified septicemia Unspecified septicemia Urinary tract infection NOS (Urinary tract infection, site not specified) Urinary tract infection NOS (Urinary tract infection, site not specified) Orthopedic aftercare NEC (Other orthopedic aftercare) Orthopedic aftercare NEC (Other orthopedic aftercare) Obstructive chronic bronchitis with (acute) exacerbation Obstructive chronic bronchitis with (acute) exacerbation Pneumonia, organism unspecified Acute on chronic systolic heart failure Acute on chronic systolic heart failure Pneumonia, organism unspecified Acute on chronic diastolic heart failure Acute on chronic diastolic heart failure Atrial fibrillation Atrial fibrillation Pneumonitis due to inhalation of food or vomitus Cellulitis and abscess of leg, except foot Hemorrhage of gastrointestinal tract, unspecified Pneumonitis due to inhalation of food or vomitus Cellulitis and abscess of leg, except foot Acute and chronic respiratory failure Congestive heart failure, unspecified Hemorrhage of gastrointestinal tract, unspecified Acute and chronic respiratory failure Congestive heart failure, unspecified Subendocardial infarction, initial episode of care Acute respiratory failure Intestinal infection due to Clostridium difficile Infection and inflammatory reaction due to indwelling urinary catheter Acute respiratory failure Subendocardial infarction, initial episode of care Acute on chronic combined systolic and diastolic heart failure Intestinal infection due to clostridium difficile Dehydration Syncope and collapse Syncope and collapse Acute on chronic combined systolic and diastolic heart failure Unspecified intestinal obstruction Unspecified intestinal obstruction Cerebral artery occlusion, unspecified with cerebral infarction Dehydration Infection and inflammatory reaction due to indwelling urinary catheter Hyposmolality and/or hyponatremia Hyposmolality and/or hyponatremia Diabetes with other specified manifestations, type II or unspecified type, not stated as uncontrolled Osteoarthrosis, localized, not specified whether primary or secondary, Coronary atherosclerosis of native coronary artery lower leg Diabetes with other specified manifestations, type II or unspecified Resection of vessel with replacement, other vessels of head type, not stated as uncontrolled and neck Obstructive chronic bronchitis with acute bronchitis Cerebral artery occlusion, unspecified with cerebral infarction Q4 26

28 Resection of vessel with replacement, other vessels of head and neck Chronic obstructive asthma with (acute) exacerbation Acute pancreatitis Obstructive chronic bronchitis with acute bronchitis Diverticulitis of colon (without mention of hemorrhage) Acute pancreatitis Anemia, unspecified Other postoperative infection Coronary atherosclerosis of native coronary artery Hepatic encephalopathy Hepatic encephalopathy Osteoarthrosis, localized, not specified whether primary or secondary, lower leg Chronic obstructive asthma with (acute) exacerbation Closed fracture of intertrochanteric section of neck of femur Other septicemia due to gram-negative organisms Other and unspecified noninfectious gastroenteritis and colitis Hypertensive heart and chronic kidney disease, unspecified, with heart Diverticulitis of colon (without mention of hemorrhage) failure and with chronic kidney disease stage I through stage IV, or unspecified Blood in stool Hyperpotassemia Altered mental status Acute posthemorrhagic anemia Osteoarthrosis, localized, not specified whether primary or secondary, Anemia, unspecified pelvic region and thigh Acute venous embolism and thrombosis of deep vessels of proximal Acute venous embolism and thrombosis of deep vessels of lower extremity proximal lower extremity Hyperpotassemia Hypertensive chronic kidney disease, unspecified, with chronic kidney disease stage V or end stage renal disease Acute posthemorrhagic anemia Diverticulosis of colon with hemorrhage Diverticulosis of colon with hemorrhage Altered mental status Atherosclerosis of native arteries of the extremities with gangrene Other septicemia due to gram-negative organisms Closed fracture of intertrochanteric section of neck of femur Alzheimer's disease Other postoperative infection Hypertensive heart and chronic kidney disease, unspecified, with heart failure and with chronic kidney disease stage I through stage IV, or unspecified Hypertensive chronic kidney disease, unspecified, with chronic kidney Atherosclerosis of native arteries of the extremities with disease stage V or end stage renal disease gangrene Other and unspecified noninfectious gastroenteritis and colitis Blood in stool Other malaise and fatigue Acute kidney failure with lesion of tubular necrosis Unspecified pleural effusion Other complications due to renal dialysis device, implant, and graft

29 Other complications due to renal dialysis device, implant, and graft Osteoarthrosis, localized, not specified whether primary or secondary, pelvic region and thigh Q1 Q ICD-9-CM Count % ICD-9-CM Count % Unspecified septicemia Unspecified septicemia Orthopedic aftercare NEC (Other orthopedic aftercare) Urinary tract infection NOS (Urinary tract infection, site not specified) Urinary tract infection NOS (Urinary tract infection, site not specified) Orthopedic aftercare NEC (Other orthopedic aftercare) Pneumonia, organism unspecified Obstructive chronic bronchitis with (acute) exacerbation Obstructive chronic bronchitis with (acute) exacerbation Pneumonia, organism unspecified Acute on chronic systolic heart failure Acute on chronic systolic heart failure Acute on chronic diastolic heart failure Acute on chronic diastolic heart failure Acute and chronic respiratory failure Atrial fibrillation Pneumonitis due to inhalation of food or vomitus Congestive heart failure, unspecified Atrial fibrillation Cellulitis and abscess of leg, except foot Subendocardial infarction, initial episode of care Acute and chronic respiratory failure Hemorrhage of gastrointestinal tract, unspecified Pneumonitis due to inhalation of food or vomitus Cellulitis and abscess of leg, except foot Subendocardial infarction, initial episode of care Acute on chronic combined systolic and diastolic heart failure Coronary atherosclerosis of native coronary artery Osteoarthrosis, localized, not specified whether primary or secondary, Hemorrhage of gastrointestinal tract, unspecified lower leg Resection of vessel with replacement, other vessels of head and neck Cerebral artery occlusion, unspecified with cerebral infarction Cerebral artery occlusion, unspecified with cerebral infarction 59 1 Intestinal infection due to clostridium difficile 56 1 Intestinal infection due to clostridium difficile 56 1 Osteoarthrosis, localized, not specified whether primary or 55 1 secondary, lower leg Coronary atherosclerosis of native coronary artery Dehydration Unspecified intestinal obstruction Acute on chronic combined systolic and diastolic heart failure Congestive heart failure, unspecified Unspecified intestinal obstruction Acute respiratory failure Acute respiratory failure Infection and inflammatory reaction due to indwelling urinary catheter Diabetes with other specified manifestations, type II or unspecified type, not stated as uncontrolled Osteoarthrosis, localized, not specified whether primary or secondary, Resection of vessel with replacement, other vessels of head pelvic region and thigh and neck Hepatic encephalopathy Hyposmolality and/or hyponatremia

30 Diabetes with other specified manifestations, type II or unspecified Obstructive chronic bronchitis with acute bronchitis type, not stated as uncontrolled Hyposmolality and/or hyponatremia Anemia, unspecified Dehydration Hepatic encephalopathy Streptococcal septicemia Osteoarthrosis, localized, not specified whether primary or secondary, pelvic region and thigh Obstructive chronic bronchitis with acute bronchitis Hyperpotassemia Diverticulosis of colon with hemorrhage Acute venous embolism and thrombosis of deep vessels of proximal lower extremity Diverticulitis of colon (without mention of hemorrhage) Chronic obstructive asthma with (acute) exacerbation Closed fracture of intertrochanteric section of neck of femur Acute pancreatitis Chronic obstructive asthma with (acute) exacerbation Aortic valve disorders Syncope and collapse Other and unspecified noninfectious gastroenteritis and colitis Other postoperative infection Diverticulitis of colon (without mention of hemorrhage) Intestinal or peritoneal adhesions with obstruction (postoperative) Streptococcal septicemia (postinfection) Other septicemia due to gram-negative organisms Unspecified pleural effusion Hyperpotassemia Acute posthemorrhagic anemia Unspecified transient cerebral ischemia Unspecified transient cerebral ischemia Infection and inflammatory reaction due to internal joint prosthesis Hypertensive chronic kidney disease, unspecified, with chronic kidney disease stage V or end stage renal disease Other pulmonary embolism and infarction Dementia, unspecified, without behavioral disturbance Chronic or unspecified gastric ulcer with hemorrhage, without mention Hypertensive heart and chronic kidney disease, unspecified, of obstruction with heart failure and with chronic kidney disease stage I through stage IV, or unspecified Other and unspecified noninfectious gastroenteritis and colitis Intestinal or peritoneal adhesions with obstruction (postoperative) (postinfection) Acute pancreatitis Diverticulosis of colon with hemorrhage Acute posthemorrhagic anemia Other septicemia due to gram-negative organisms Hypertensive heart and chronic kidney disease, unspecified, with heart Acute systolic heart failure failure and with chronic kidney disease stage I through stage IV, or unspecified Acute kidney failure with lesion of tubular necrosis Chronic or unspecified gastric ulcer with hemorrhage, without mention of obstruction Acute systolic heart failure Other pulmonary embolism and infarction Unspecified pleural effusion Acute kidney failure with lesion of tubular necrosis