# Comparing rules for truncating hospital length of stay

## Détails

ID Serval

serval:BIB_C7D551F51BC9

Type

**Article**: article d'un périodique ou d'un magazine.

Collection

Publications

Institution

Titre

Comparing rules for truncating hospital length of stay

Périodique

Casemix Quarterly

Statut éditorial

Publié

Date de publication

2000

Volume

2

Numéro

1

Pages

3-11

Notes

SAPHIRID:47974

Résumé

Most distributions of hospital length of stay are asymmetric, with a long right tail and some very large observations (outliers). These features vitiate the reliability of many statistical summaries, such as the arithmetic mean, and comparisons based on them. A common remedy is to truncate (i.e., remove) values outside some limits and take the arithmetic mean of the remaining values. In general, the limits are based on a position measure (e.g., mean, median, quartiles) and a scale measure (e.g., standard deviation, median absolute deviation, interquartile range). In addition, a scale transformation (usually the logarithm) is frequently used.Using a data base with almost five millions hospital stays from five European countries, this paper explores the performance of five common truncation rules combining various options on transformation, position and scale. These rules are compared with a new one called " approximated quartile based truncated mean " or AQTM. The AQTM is based on a parametric model which takes into account the shape of the data distribution. This paper shows that the usual truncation rules produce very different estimates, and that most of the usual rules are biased with respect to the AQTM. There is one exception based on symmetric truncation beyond the interquartile range on the logarithmic scale. Since the AQTM is computationally as simple as the usual rules, but has a better foundation, it is preferred. [Authors]

Mots-clé

Length of Stay , Bias (Epidemiology) , Statistical Distributions , Outliers, DRG , Statistics as Topic

Création de la notice

14/03/2008 10:20

Dernière modification de la notice

20/08/2019 15:43