Table 4.
Differences in Disease Capture by Rank for ICD-9-CM and ICD-10-CM for Reportable Diseases
| National Health Reportable Diseases | ICD-9-CM Rank | ICD-10-CM Rank | Explanation |
| Amebiasis | 3 | 5 | I-10 has 3 additional codes and breaks out specific site of abscess |
| Animal bites** | 4 | 5 | I-10 more specific and span more sections of codes |
| Arthropod borne infections | 2 | 5 | Codes similar for both systems but I-10 more specific and offers more classification types. |
| Bartonellosis | 3 | 5 | I-10 more codes and covers more in the description i.e. Oroya fever |
| Basidiobolus | 1 | 3 | Found in I-10 under “other zygomycoses” only and not found in I-9. |
| Blastomycosis | 2 | 5 | I-10 has more codes/descriptions |
| Campylobacter enteritis | 3 | 5 | I-9 uses two general codes to capture (009.1 +008.43) |
| Carbon monoxide poisoning | 2 | 5 | I-10 has many more codes/descriptions |
| Chickenpox | 3 | 5 | I-10 has more codes/descriptions |
| Ciguatera fish poisoning | 2 | 5 | I-10 has more codes/descriptions |
| Clostridium perfringens intoxication | 1 | 5 | I-10 does code this while I-9 has no code |
| Coccidioidomycosis* | 3 | 5 | I-10 has more codes/descriptions |
| Conjunctivitis: acute | 3 | 5 | I-10 has more codes/descriptions |
| Cysticercosis | 2 | 5 | I-10 has more codes/descriptions |
| Dengue fever | 4 | 5 | I-10 has one additional code/description |
| Encephalitis | 3 | 5 | I-10 has many more codes and is more specific and captures more |
| Gonococcal infection* | 4 | 5 | I-10 has more codes and codes related to pregnancy complications |
| Haemophilus influenzae (invasive disease)* | 2 | 5 | I-10 has more codes/descriptions |
| Hansen's disease* | 4 | 5 | I-10 has more codes/descriptions |
| Hepatitis A acute/chronic* | 4 | 5 | Captured by both with similar descriptions but I-10 has an “other” category |
| Hepatitis B acute/chronic* | 5 | 4 | Captured by both systems but I-9 more specific for some categories |
| Hepatitis B, surface antigen* | 1 | 5 | I-9 does not have a code for this |
| Hepatitis C, acute/chronic* | 5 | 4 | Captured by both systems but descriptions are different and I-9 more specific with additional code |
| Hepatitis D | 5 | 4 | Captured by both systems but descriptions are different and I-9 more specific with additional code |
| Herpes, neonatal or genital | 3 | 5 | I-10 much more specific |
| Histoplasmosis | 5 | 2 | I-9 much more specific. I-10 requires additional codes for higher level of specificity/granularity |
| HTLV (human T-lymphotrophic virus | 3 | 5 | I-10 more specific |
| Hyperthermia | 3 | 5 | I-10 has more codes/descriptions |
| Hypothermia | 5 | 3 | I-9 more specific |
| Legionellosis* | 4 | 5 | I-10 includes an additional code for nonpneumonic Legionnaires disease |
| Listeriosis | 2 | 5 | I-10 has more codes/descriptions/specificity |
| Lyme disease | 2 | 5 | I-10 has more codes/descriptions/specificity |
| Marburg virus | 4 | 5 | Captured by both but I-10 more specific stating “Marburg virus” while I-9 states “other specified diseases due to viruses.” |
| Malaria* | 3 | 5 | I-10 much more specific |
| Maple syrup urine disease | 4 | 5 | Captured by both but I-10 more specific in description |
| Measles* | 3 | 5 | I-10 much more specific |
| Meliodiosis | 3 | 5 | I-10 more specific with more codes |
| Meningitis, viral, bacterial, fungal, parasitic | 3 | 5 | I-10 more specific with more codes |
| Meningococcal disease* | 3 | 5 | I-10 more specific with more codes |
| Mercury poisoning | 3 | 5 | I-10 more specific with more codes |
| Monkeypox | 4 | 5 | Captured by both but I-10 more specific in description |
| Mumps* | 3 | 5 | I-10 more specific with more codes |
| Neonatal herpes | 3 | 5 | I-10 more specific with more codes |
| Neonatal bacterial sepsis | 2 | 5 | I-10 more specific with more codes |
| Foodborne outbreak | 3 | 5 | I-10 more specific with more codes |
| Outbreaks or illnesses in child care settings | 1 | 3 | Both have one code but I-10 is more specific in place of occurrence |
| Nosocomial outbreak | 1 | 5 | Captured by I-10 |
| Pediculosis | 5 | 4 | Captured by both systems but I-9 has one additional code |
| Pelvic inflammatory disease | 4 | 5 | Captured by both but I-10 has more specific codes |
| Pertussis* | 3 | 5 | Captured by both systems but I-10 has more specific codes pertaining to poisoning by pertussis vaccine which I-9 does not include |
| Pesticide related illness | 3 | 5 | I-10 more specific codes |
| Plague* | 5 | 4 | Captured by both but I-9 has one more code-secondary pneumonic plague |
| Poliomyelitis* | 5 | 3 | I-9 has many more specific codes but specificity may be outdated |
| Perinatal exposure of NB to HIV | 2 | 4 | I-10 more specific and has O codes to denote a complication in pregnancy due to HIV exposure |
| Pneumococcal disease | 2 | 5 | I-10 more codes/more specific |
| Primary congenital hypothyroidism | 2 | 5 | I-10 more codes/more specific |
| Rabies* | 3 | 5 | I-10 more codes/more specific |
| Rickettsial disease/infection | 2 | 5 | I-10 more codes/more specific |
| Rocky mountain spotted fever* | 4 | 5 | I-10 more specific description |
| Rubella* | 2 | 5 | I-10 more codes/more specific |
| Scombroid fish poisoning | 2 | 5 | I-10 more specific for fish type |
| Smallpox* | 5 | 2 | I-9 more codes /more specific but could be due to smallpox being eradicated |
| Sporotrichosis | 2 | 5 | I-10 more codes/more specific |
| Staphylococcus aureus | 3 | 5 | I-10 more codes/more specific |
| Streptococcal infections* | 3 | 5 | I-10 has more codes; descriptions are different |
| Syphilis* | 3 | 5 | I-10 more specific with more specific categories |
| T-2 mycotoxins | 1 | 5 | Not captured at all in I-9 |
| Tetanus* | 3 | 5 | I-10 has more codes related to OB and the neonate |
| Toxins (Ricin, S. entertoxin | 2 | 4 | I-10 more detailed; includes use of extensions for initial encounter |
| Tularemia* | 4 | 5 | Captured by both; I-10 one more code |
| Typhoid* | 2 | 5 | I-10 more codes/more specific |
| Typhus, louse-borne | 4 | 5 | I-10 more specific with one more code |
| Vaccine adverse reactions | 5 | 3 | I-9 descriptions provide more detail about the virus the vaccine is protecting against while I-10 group many together |
| Varicella* | 4 | 5 | I-10 has one more code; varicella keratitis |
| Viral hemorrhagic fever | 2 | 5 | I-10 more specific with many more codes |
| Vancomycin-resistant enterococci* | 3 | 1 | Found in I-9 under “Infections with microorganisms resistant to other specified drugs” |
*
CDC National Reportable Disease
**
Multiple S codes by site. ICD-10 is more specific. Also, ICD-10 spans T codes and W codes. More than 100 codes that deal with bites and area of effect for I-10.
Ranking:
5= Diagnosis is fully captured by the code/codes
4=Diagnosis is almost fully captured by the code/codes
3=Diagnosis is partially captured by the code/codes
2=Diagnosis is less than partially captured by the code/codes
1=Diagnosis is not captured by the code/codes