Documentation

ICD-9 codes

The seminal article on this topic is from Billings, et al. (1993). As defined in this article, preventable hospitalizations (also called ambulatory care sensitive conditions) are "diagnoses for which timely and effective outpatient care can help to reduce the risks of hospitalization by either preventing the onset of an illness or condition, controlling an acute episodic illness or condition, or managing a chronic disease or condition..." Using guidelines obtained from the principal author, information on preventable hospitalizations in Missouri is collected and displayed for the public in an interactive data tool called a MICA (Missouri Information for Community Assessment).

Hospital exclusions As with other community data profiles and the MICAs, the term hospitalizations in this version of the Preventable Hospitalizations MICA now refers to acute care hospital discharges of Missouri residents from non-federal and non-state short-term (average length of stay less than 30 days) general and specialty hospitals whose facilities are open to the general public. Excluded from the hospitalization data are discharges from long-term care facilities, as well as those from long-term care units within general hospitals (i.e., swing bed, skilled nursing, and intermediate care units). Also excluded are discharges from residential care facilities and residential care units within licensed hospital facilities. The previous Preventable Hospitalizations MICA did not impose these restrictions.

Inpatient admissions Hospitalization data for this MICA reflect all sources of inpatient admissions, including direct admissions, transfers from emergency departments or other within-hospital units, and transfers from external facilities (i.e., other hospitals or long-term care facilities). The source of these data is the Patient Abstract System (PAS) data file, which is compiled from hospital discharge records that are filed with the Department by state law. The reporting requirements for the PAS have been in place in Missouri continuously since 1993.

Missing information In some instances, certain data values in the patient record are missing or miscoded. Discharges with missing or miscoded data values are included in the statewide totals, but may not be included within the displayed categories of certain variables (e.g., race, county of residence, sex, payor type). Thus, a total of all categories of a variable may not equal the statewide total for that variable. Patients with a missing state of residence were deleted from the analysis file. Those discharges records identified as Missouri residents, but missing a county identifier, are included in the statewide totals only.

In the previously posted MICA on Preventable Hospitalizations, discharge records with missing information on race, sex, payor type, or county were removed from the data before tabulation. These records are now included as described above.

Comparisons with other MICAs The data for the Preventable Hospitalizations MICA has a few selection criteria differences from those normally used in other currently posted MICAs. Newborns are a special category of hospital discharges that are not included in the normal MICAs and community profiles on hospitalizations. In the Preventable Hospitalizations MICA, newborns are included, except where inappropriate.

Some of the preventable conditions require the identification of procedures or secondary diagnoses, rather than focusing exclusively on the principal diagnosis for each discharge. A list of the diagnoses and procedures used to define preventable hospitalizations can be found under the Definitions section of this MICA. All diagnoses and procedures were specified using the International Classification of Diseases, Ninth Revision (ICD-9-CM).

REFERENCES 

Diagnoses and Procedures Definitions used for Preventable Hospitalizations

(An "x" with 3-digit codes indicates the selection of all 4- and 5-digit codes, also. All diagnoses and procedures specified at the International Classification of Diseases, Ninth Revision (ICD-9-CM) level.) 

Angina
Principal diagnosis of 4111, 4118, 413x and not with any procedure below 87000. 
Asthma

Principal diagnosis of 493x. 
Bacterial Pneumonia

Principal diagnosis of 481x, 4822, 4823, 4829, 483x, 485x, 486x and any secondary diagnosis that is not 2826 and age is 60 days and above. 
Cellulitis

Principal diagnosis of 681x, 682x, 683x, or 686x and not with any procedure below 87000 except when the only procedure performed is one of 86000 through 86099.  
Chronic Obstructive Pulmonary

Principal diagnosis of 491x, 492x, 494x, 496x or a principal diagnosis of 4660 with a secondary diagnosis of 491x, 492x, 494x, 496x. 
Congenital Syphilis

Principal Diagnosis is V3x (newborn) and any secondary diagnosis of 090x. 
Congestive Heart Failure

Principal diagnosis of 428x, 40201, 40211, 40291, 5184 and not with any procedure code of 3601, 3602, 3605, 3610-36199, 375x, 3770-37799. 
Convulsions

Principal diagnosis of 7803 and excludes newborns. 
Dehydration - Volume Depletion

Principal diagnosis of 2765. 
Dental Conditions

Principal diagnosis of 521x, 522x, 523x, 525x, 528x. 
Diabetes

Principal diagnosis of 2500-2503, 2508-2509. 
Ear, Nose, Throat - Severe Infections

Principal diagnosis of 382x, 462x, 463x, 465x, 4721 and not a procedure of 2001. 
Epilepsy

Principal diagnosis of 345x. 
Failure To Thrive

Principal diagnosis of 7834 and age is not 1 or above. 
Gastroenteritis

Principal diagnosis of 5589. 
Hypertension

Principal diagnosis of 401x (but not 4010 or 4019), 40200, 40210, 40290 and not with any procedure code of 3601, 3602, 3605, 3610-36199, 375x, 3770-37799. 
Hypoglycemia

Principal diagnosis of 2512. 
Immunization Preventable

Principal diagnosis of 033x, 390x, 391x, 037x, 045x or a principal diagnosis of 3200 for ages greater than 0 but less than 6. 
Kidney/Urinary Infection

Principal diagnosis of 590x, 5990, 5999. 
Nutritional Deficiencies (Includes Iron Deficiency Anemia)

Principal diagnosis of 260x, 261x, 262x, 2680, 2681 or a principal diagnosis of 2801, 2808, 2809 for ages greater than 0 but less than 6. 
Pelvic Inflammatory Disease

Principal diagnosis of 614x and sex is female and not with any procedure from 68300 through 68999. 
Tuberculosis - Pulmonary

Principal diagnosis of 011x 012x, 013x, 014x, 015x, 016x, 017x, 018x.