Tiago Silva-Costa

Factors influencing hospital high length of stay outliers

BackgroundThe study of length of stay (LOS) outliers is important for the management and financing of hospitals. Our aim was to study variables associated with high LOS outliers and their evolution over time.MethodsWe used hospital administrative data from inpatient episodes in public acute care hospitals in the Portuguese National Health Service (NHS), with discharges between years 2000 and 2009, together with some hospital characteristics. The dependent variable, LOS outliers, was calculated for each diagnosis related group (DRG) using a trim point defined for each year by the geometric mean plus two standard deviations. Hospitals were classified on the basis of administrative, economic and teaching characteristics. We also studied the influence of comorbidities and readmissions. Logistic regression models, including a multivariable logistic regression, were used in the analysis. All the logistic regressions were fitted using generalized estimating equations (GEE).ResultsIn near nine million inpatient episodes analysed we found a proportion of 3.9% high LOS outliers, accounting for 19.2% of total inpatient days. The number of hospital patient discharges increased between years 2000 and 2005 and slightly decreased after that. The proportion of outliers ranged between the lowest value of 3.6% (in years 2001 and 2002) and the highest value of 4.3% in 2009. Teaching hospitals with over 1,000 beds have significantly more outliers than other hospitals, even after adjustment to readmissions and several patient characteristics.ConclusionsIn the last years both average LOS and high LOS outliers are increasing in Portuguese NHS hospitals. As high LOS outliers represent an important proportion in the total inpatient days, this should be seen as an important alert for the management of hospitals and for national health policies. As expected, age, type of admission, and hospital type were significantly associated with high LOS outliers. The proportion of high outliers does not seem to be related to their financial coverage; they should be studied in order to highlight areas for further investigation. The increasing complexity of both hospitals and patients may be the single most important determinant of high LOS outliers and must therefore be taken into account by health managers when considering hospital costs.

Implications of Data Quality Problems within Hospital Administrative Databases

Administrative data, even with some coding irregularities, is easily accessible, inexpensive, and includes episodes from several years for large populations. This routine data can be used to study hospital performance and to screen potential problems in healthcare. In this context, the quality of data is a fundamental issue if we want to achieve reliable results. In fact, the problem of poor data quality cannot be ignored and should more and more be considered. In this paper we present some issues about quality problems, expose some examples of poor data in administrative databases and discuss some potential implications of these problems.

Detection of Adverse Events Through Hospital Administrative Data

This study aims to estimate and describe the incidence of adverse events (AE) registered in Portuguese public hospitals and consequently to determine the feasibility of using hospital administrative data as a tool for AE surveillance. A retrospective observational study using hospital administrative data was performed to detect the incidence of AE based on a selection of ICD-9-CM codes (diagnoses and external causes). All episodes in public hospitals in the period 2000–2010 were included. AE were divided in three main categories: complications of surgical or medical procedures, misadventures of surgical and medical care, and adverse drug events (ADE). The ADE subgroup was further subdivided in: poisoning, late effect, and adverse drug reaction. Over the studied period, the algorithm was able to detect 543,242 episodes with AE events (3.7% of all episodes), with an in-hospital mortality rate of 6.3%, and a median length-of-stay of 8 days. In a scenario of underreporting of AE, this administrative data approach in an important complement to the other existing surveillance techniques.

Invalid inpatient stays and their potential reimbursement

An inpatient is usually defined as a patient who is admitted to a hospital or clinic for treatment that requires at least one overnight stay. However, since 1 August 2006, and for reimbursement purposes, under Portuguese law the length of stay must be longer than 24 hours to be considered a valid inpatient stay. The Portuguese National Health System hospitals are financed through two different schemes. For patients with a third party responsible for health expenditure, the hospital charges a fixed price by DRG for each inpatient stay, and for some outpatient visits such as chemotherapy, ambulatory surgery, and dialysis, among others. For patients covered solely by the National Health System, hospitals are financed through an annual agreement. Under this agreement, there is a single fixed price for inpatient stays as well as those outpatient visits which have a DRG associated. Each type of production is valued by applying that price, adjusted by the case-mix index for that type, to the amount of equivalent inpatient stays (adjusted to the medium length of stay outside the considered normality limits) or outpatient visits. Stays under 24 hours, since they are registered as inpatient stays, are not eligible for inpatient reimbursement under either scheme. In addition, they are also not considered proper outpatient visits, and are not paid as such to the hospital. Even so, the hospital incurs costs with these patients, often including surgical procedures or other costly treatments. Our aim is to show how invalid inpatient stays affect both the hospital’s budget and funding.