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. 2018 Jun 13;13(6):e0198522.
doi: 10.1371/journal.pone.0198522. eCollection 2018.

The association between outcome-based quality indicators for intensive care units

Ilona W M Verburg  1 , Evert de Jonge  2 , Niels Peek  3 , Nicolette F de Keizer  1
Affiliations

The association between outcome-based quality indicators for intensive care units

Ilona W M Verburg et al. PLoS One. .

Abstract

Purpose: To assess and improve the effectiveness of ICU care, in-hospital mortality rates are often used as principal quality indicator for benchmarking purposes. Two other often used, easily quantifiable, quality indicators to assess the efficiency of ICU care are based on readmission to the ICU and ICU length of stay. Our aim was to examine whether there is an association between case-mix adjusted outcome-based quality indicators in the general ICU population as well as within specific subgroups.

Materials and methods: We included patients admitted in 2015 of all Dutch ICUs. We derived the standardized in-hospital mortality ratio (SMR); the standardized readmission ratio (SRR); and the standardized length of stay ratio (SLOSR). We expressed association through Pearson's correlation coefficients.

Results: The SMR ranged from 0.6 to 1.5; the SRR ranged from 0.7 to 2.1; and the SLOSR ranged from 0.7 to 1.3. For the total ICU population we found no significant associations. We found a positive, non-significant, association between SMR and SLOSR for admissions with low-mortality risk, (r = 0.25; p = 0.024), and a negative association between these indicators for admissions with high-mortality risk (r = -0.49; p<0.001).

Conclusion: Overall, we found no association at ICU population level. Differential associations were found between performance on mortality and length of stay within different risk strata. We recommend users of quality information to take these three outcome indicators into account when benchmarking ICUs as they capture different aspects of ICU performance. Furthermore, we suggest to report quality indicators for patient subgroups.

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Flowchart of admissions included for the quality indicators for in-hospital mortality, readmission to the ICU and ICU length of stay.
Fig 2
Fig 2. Pairs of quality indicators plotted against each other on ICU level.
Fig 2A: standardized in-hospital mortality ratio (SMR) against standardized ICU readmission within 48 hours ratio (SRR). Fig 2B: standardized length of stay ratio (SLOSR) against SMR. Fig 2C: SLOSR against SRR.
Fig 3
Fig 3. Quality indicators SMR and SLOSR plotted against each other on ICU level for patients grouped based on severity of illness defined using the probability of mortality.
Fig 3A: probability of mortality smaller than 0.3. Fig 3B: probability of mortality larger or equal to 0.3 and smaller than 0.7. Fig 3C: probability of mortality larger or equal to 0.7.
See this image and copyright information in PMC

References

    1. Kolfschoten NE, Kievit J, Gooiker GA, van Leersum NJ, Snijders HS, Eddes EH, et al. Focusing on desired outcomes of care after colon cancer resections; hospital variations in 'textbook outcome'. Eur J Surg Oncol. 2013;39(2):156–163. doi: 10.1016/j.ejso.2012.10.007 - DOI - PubMed
    1. Goldstein H, Spiegelhalter DJ. League Tables and Their Limitations: Statiatical Issues in Comparisons of Institutional Performance. Journal of the Royal Statistical Society 1996;159(3):358–433. doi: 10.2307/2983325 - DOI
    1. Halpern NA, Pastores SM. Critical care medicine in the United States 2000–2005: an analysis of bed numbers, occupancy rates, payer mix, and costs. Critical care medicine. 2010;38(1):65–71. doi: 10.1097/CCM.0b013e3181b090d0 - DOI - PubMed
    1. Berenholtz SM, Dorman T, Ngo K, Pronovost PJ. Qualitative review of intensive care unit quality indicators. J Crit Care. 2002;17(1):1–12. - PubMed
    1. Flaatten H. The present use of quality indicators in the intensive care unit. Acta Anaesthesiol Scand. 2012;56(9):1078–1083. doi: 10.1111/j.1399-6576.2012.02656.x - DOI - PubMed

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