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ICD Code: 493. Asthma



ICD Code: 493. Article Review
Title: Morris RD et al; "Childhood Asthma Surveillance Using Computerized Billing Records: A Pilot Study." Public Health Reports; V.112; 11/97; p506
      Asthma is the most common chronic disease of childhood, affecting an estimated 4.8 million children in the U.S.
      STUDY DESIGN: The present paper describes a collaboration between the Wisconsin State Division of Health and the Medical College of Wisconsin to develop a system for childhood asthma surveillance in Milwaukee that might be adapted for use in other cities in the U.S. The present authors made arrangements to obtain current patient billing data from CHW beginning in March 1994. The retrospective data back to January 1, 1993 was also requested.
      SURVEILLANCE PROTOCOL: The recommended surveillance protocol relied on the use of computerized data that were already being collected by hospitals (including emergency department, or ED, records), community clinics, and health maintenance organizations (HMOs). The primary tool for ongoing surveillance were the billing data for ED visits and inpatient admissions to Children's Hospital of Wisconsin (CHW). The choice of CHW was based on the analysis of data from the Hospital Discharge Data Base maintained by the Wisconsin Office of Health Care Information, which indicated that more than 90% of inpatient care for asthma in Milwaukee County in 1992 was provided by CHW.
      PATIENT SUBGROUPS: Children visiting CHW in 1994 were grouped into four categories defined by whether they had repeated hospital admissions, repeated ED visits, both, or neither. These groupings were based on the notion that repeated hospital-based care for asthma would frequently represent inappropriate use of care and that these children would be an important target for intervention. It was also believed that repeated use of EDs without repeat hospital admissions indicated a different set of problems (such as use of ED facilities for primary care) from repeated hospital admissions, which represent more severe exacerbations.
      HEALTH CARE UTILIZATION: The largest group (Group A), with 76% of the children, had no repeat admissions or ED visits and accounted for about half of all admissions and ED visits. Group B (more than 1 ED visit, 0 to 1 admissions) included 17% of the children and accounted for 41% of emergency visits but only 8% of hospital admissions. Group C (0 to 1 ED visit, more than 1 admission), with 5% of the children, accounted for 22% of hospital admissions but only 1% of ED visits. Finally, the 3% of children who comprised Group D, who had both repeated admissions and repeated ED visits, accounted for 16% of admissions and 9% of ED visits.
      The ratio of ED visits to hospital admissions ranged from 0.14 for Group C to 11.3 for Group B. Overall, the 20% of children with repeated ED visits accounted for 50% of all ED visits while the 7% of children with repeated hospital admissions accounted for 38% of all admissions.
      TEMPORAL PATTERNS OF ED VISITS: The data showed wide fluctuations in daily counts ranging from 5 to 12 visits per day for the inner-city children and from 0 to 7 visits per day for non-inner-city children. The highest rates occurred in the spring and fall of the year.
      DISCUSSION: Only 25% of children had repeat hospital admissions or ED visits, but they accounted for 52% of ED visits and 46% of admissions. One group (Group B) appeared to use the ED as a source of primary care, with more than 11 ED visits for each hospital admission. Clearly, this group should be the target of interventions to improve disease management and access to care.
      The present study found that in Milwaukee most of the asthma care for infants and younger children was delivered by one specialized pediatric ED. In other cities in which this is true, interventions designed to reach parents of young children with asthma can reach a high percentage of their target population if they are conducted at these specialized facilities. Older children, on the other hand, are substantially less likely than younger children to receive their care at specialized pediatric EDs. Surveillance based on data from a small number of specialized EDs will be less representative for older children and interventions intended to reach older children will miss many children if they are limited to specialized pediatric EDs.

Search Criteria: Text - Public Health Reports; V.112; 11/97; p506