Observation stays in administrative claims databases: underestimation of hospitalized cases.

View Abstract

PURPOSE

Recent policy changes in the USA have led to an increasing number of patients being placed into observation units rather than admitted directly to the hospital. Studies of administrative data that use inpatient diagnosis codes to identify cohorts, outcomes, or covariates may be affected by this change in practice. To understand the potential impact of observation stays on research using administrative healthcare data, we examine the trends of observation stays, short (≤2 days) inpatient admissions, and all inpatient admissions.

METHODS

We examined a large administrative claims database of commercially insured individuals in the USA between 2002 and 2011. Observation stays were defined on the basis of the procedure codes reimbursable by Medicare or commercial insurers. We report monthly rates of observation stays and short inpatient admissions overall and by patient demographics.

RESULTS

We identified 5 355 752 observation stays from 2002 to 2011. Over the course of study, the rate of observation stays increased, whereas the rate of short inpatient stays declined. The most common reason for observation stays was nonspecific chest pain, also the third most common reason for short inpatient stays. The increasing trend of observation stays related to circulatory diseases mirrors the decreasing trend of short inpatient stays.

CONCLUSIONS

The use of observation stays has increased in patients with commercial insurance. Failure to account for observation stays may lead to an under-ascertainment of hospitalizations in contemporary administrative healthcare data from the USA.

Investigators
Abbreviation
Pharmacoepidemiol Drug Saf
Publication Date
2014-05-28
Volume
23
Issue
9
Page Numbers
902-10
Pubmed ID
24866538
Medium
Print-Electronic
Full Title
Observation stays in administrative claims databases: underestimation of hospitalized cases.
Authors
Overman RA, Freburger JK, Assimon MM, Li X, Brookhart MA