Table E1: Basic Characteristics of Patients According to AKIN Stages

Electronic Supplemental Material (ESM)

SAPS 3 database description:

The SAPS 3 project was conducted by the SAPS 3 Outcomes Research Group. The project was endorsed by the European Society for Intensive Care Medicine (ESICM, and conducted in cooperation with the Section on Health Services Research and Outcome of the ESICM. The complete lists of boards and participants can be found in Appendix D of the Electronic Supplementary Material (ESM) to the main manuscript, as can be the details about the SAPS 3 Hospital Outcome Cohort building [1]

The SAPS 3 Hospital Outcome Cohort comprises 16,784 patients from 303 ICUs. Data were collected at ICU admission, on days 1 and 2 of the ICU stay. Data from the day of admission (aside from sociodemographic data such as age and sex) were categorized into different levels: (i) data about the condition of the patient before ICU admission, such as chronic conditions and medical diseases; (ii) data about the patient’s condition at ICU admission, such as the reason for admission, infection at admission, and surgical status; and (iii) data about the patient’s physiologic derangement at ICU admission. These data were collected within an hour before or after ICU admission.

On the following days of the ICU stay, further information was collected: severity of illness, as measured by the SAPS II [2]; number and severity of organ dysfunction, as measured by the Sequential Organ Failure Assessment (SOFA) [3] length of ICU and hospital stay; and outcome data, including vital status at ICU and hospital discharge.

Data quality

Recorded data were evaluated for completeness of the documentation and reliability. Inter-rater quality control was performed through rescoring of the data and calculation of kappa coefficients and intra-class correlation coefficients, as appropriate. Data quality was excellent, results have been presented in detail in the ESM file of the SAPS 3 primary report [1].

Reference List

1. Metnitz PG, Moreno RP, Almeida E, Jordan B, Bauer P, Campos RA, Iapichino G, Edbrooke D, Capuzzo M, Le G, Jr. (2005) SAPS 3--From evaluation of the patient to evaluation of the intensive care unit. Part 1: Objectives, methods and cohort description. Intensive Care Med 31: 1336-1344

2. Le Gall Jr, Lemeshow S, Saulnier F (1993) A new Simplified Acute Physiology Score (SAPS II) based on a European/North American multicenter study. JAMA 270: 2957-2963

3. Vincent JL, de MA, Cantraine F, Moreno R, Takala J, Suter PM, Sprung CL, Colardyn F, Blecher S (1998) Use of the SOFA score to assess the incidence of organ dysfunction/failure in intensive care units: results of a multicenter, prospective study. Working group on "sepsis-related problems" of the European Society of Intensive Care Medicine. Crit Care Med 26: 1793-1800

Table E1: Basic characteristics of patients according to AKIN stages:

* serum creatinine on admission
Table E2: Basic descriptive characteristics of patients according to RIFLE stages:

* serum creatinine on admission

Table E3: Sensitivity Analysis for assigning Urinary Output (<0.5 ml/kg/h)

First Analysis:

Urinary Output (< 0.5ml/kg/h) assigned to Stage 2/INJURY

Second Analysis:

Urinary Output (<0.5 ml/kg/h) assigned toStage 1/RISK

To check stability of urinary output allocation a sensitivity analysis was performed. In the first analysis (assigning the patients with urinary output of < 0.5ml/kg/h to the more serious groups AKIN Stage 2 and RIFLE Injury, respectively) the overall mortality in Stage 2 and Injury had lower values than in the second analysis. In the second analysis (assigning the cases to the less serious groups (Stage 1 and RISK, respectively)) the overall mortality of the lower subgroup surprisingly was decreased. In contrast mortality in the stage 2/Risk subgroup was increased and approximated mortality of Stage 3 /Failure.