Value¶

The value side of every variable: how far the recorded number can be from the true one. Two things set that. Resolution is how the value was written down: the step it was recorded at, and the coarser values people round to (heaping). Accuracy is how far the instrument or method is from the truth before any rounding.

Most of what is here is resolution, from fitted rounding models (the method). Accuracy is described where it is known; for most instruments it is still to be added.

What an anchor is: Aim and terms. Every variable's anchor, and which are unsettled: Anchor decisions.

Fitted rounding models (heaped values)¶

Variable	Unit	Resolution	Model study
Estimated blood loss	mL	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of estimated blood loss
Height	cm	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of height
Intraoperative crystalloid	mL	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of intraoperative crystalloid
Intraoperative urine output	mL	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of intraoperative urine output
Propofol bolus	mg	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of propofol bolus
Weight	kg	heaped: a mixture of rounding modes (see the value model)	Rounding and heaping of weight

Charted times (fitted)¶

Variable	Unit	Resolution	Model study
Anesthesia end time	sec	heaped: a mixture of rounding modes (see the value model)	How the anesthesia end time was charted
Anesthesia start time	sec	heaped: a mixture of rounding modes (see the value model)	How the anesthesia start time was charted
Operation end time	sec	heaped: a mixture of rounding modes (see the value model)	How the operation end time was charted
Operation start time	sec	heaped: a mixture of rounding modes (see the value model)	How the operation start time was charted

Derived from other variables¶

Variable	Unit	Resolution	Model study
Anaesthesia duration	min	derived from anestart, aneend	—
Anaesthesia start to incision	min	derived from anestart, opstart	—
Body mass index	kg/m2	derived from height, weight	Body mass index, derived from its inputs
Length of hospital stay (dis - adm)	days	derived from adm, dis	—
Operation duration	min	derived from opstart, opend	—
Operation end to anaesthesia end	min	derived from opend, aneend	—

Resolution set by the source¶

Variable	Unit	Resolution	Model study
Hematocrit	%	by analyser: cbc 0.1 %, blood_gas 1 %	—

Resolution set by the decimal¶

Variable	Unit	Resolution	Model study
Preoperative PaO₂	mmHg	0.1 mmHg when a decimal is recorded, else 1 mmHg	—

One resolution¶

Variable	Unit	Resolution	Model study
Activated partial thromboplastin time	sec	0.1 sec, nearest	—
Admission time from casestart	sec	86400 sec, floor	—
Alanine transferase	IU/L	1 IU/L, nearest	—
Albumin	g/dL	0.1 g/dL, nearest	—
Ammonia	mcg/dL	1 mcg/dL, nearest	—
Arterial oxygen saturation	%	1 %, nearest	—
Asparate transferase	IU/L	1 IU/L, nearest	—
Base excess	mmol/L	0.1 mmol/L, nearest	—
Bicarbonate	mmol/L	0.1 mmol/L, nearest	—
Blood urea nitrogen	mg/dL	1 mg/dL, nearest	—
C-reactive protein	mg/dL	0.01 mg/dL, nearest	—
Case end	sec	1 sec, floor	—
Chloride	mmol/L	1 mmol/L, nearest	—
Creatinine	mg/dL	0.01 mg/dL, nearest	—
Creatinine clearance	mL/min	1 mL/min, nearest	—
Discharge time from casestart	sec	86400 sec, floor	—
Epinephrine	mcg	1 mcg, nearest	—
Erythrocyte sedimentation rate	mm/hr	1 mm/hr, nearest	—
Glomerular filtration rate	mL/min/1.73 m2	0.1 mL/min/1.73 m2, nearest	—
Glucose	mg/dL	1 mg/dL, nearest	—
Hemoglobin	g/dL	0.1 g/dL, nearest	—
Ionized Calcium	mmol/L	0.01 mmol/L, nearest	—
Lab timestamp (seconds from casestart)	sec	1 sec, floor	—
Lactate	mmol/L	0.1 mmol/L, nearest	—
Midazolam	mg	0.5 mg, nearest	—
Partial pressure of CO₂	mmHg	1 mmHg, nearest	—
Partial pressure of O₂	mmHg	1 mmHg, nearest	—
Platelet count	×1000/mcL	1 ×1000/mcL, nearest	—
Potassium	mmol/L	0.1 mmol/L, nearest	—
Preoperative GOT	IU/L	1 IU/L, nearest	—
Preoperative GPT	IU/L	1 IU/L, nearest	—
Preoperative HCO3-	mmol/L	0.1 mmol/L, nearest	—
Preoperative K	mmol/L	0.1 mmol/L, nearest	—
Preoperative Na	mmol/L	1 mmol/L, nearest	—
Preoperative PaCO₂	mmHg	0.1 mmHg, nearest	—
Preoperative SpO₂	%	0.1 %, nearest	—
Preoperative aPTT	sec	0.1 sec, nearest	—
Preoperative albumin	g/dL	0.1 g/dL, nearest	—
Preoperative base excess	mmol/L	0.1 mmol/L, nearest	—
Preoperative blood urea nitrogen	mg/dL	1 mg/dL, nearest	—
Preoperative creatinine	mg/dL	0.01 mg/dL, nearest	—
Preoperative glucose	mg/dL	1 mg/dL, nearest	—
Preoperative hemoglobin	g/dL	0.1 g/dL, nearest	—
Preoperative pH		0.001 , nearest	—
Preoperative platelet count	x1000/mcL	1 x1000/mcL, nearest	—
Probably phosphorus (unconfirmed): not in lab_parameters.csv		0.1 , nearest	—
Prothrombin time (INR)	INR	0.01 INR, nearest	—
Prothrombin time (sec)	sec	0.1 sec, nearest	—
Sodium	mmol/L	1 mmol/L, nearest	—
Total bilirubin	mg/dL	0.1 mg/dL, nearest	—
Total protein	g/dL	0.1 g/dL, nearest	—
Vecuronium	mg	1 mg, nearest	—
White blood cell count	×1000/mcL	0.01 ×1000/mcL, nearest	—
pH		0.01 , nearest	—

Computed values¶

Variable	Unit	Resolution	Model study
Fibrinogen	mg/dL	computed value: interval to the neighbouring reachable values	—
Preoperative PT	%	computed value: interval to the neighbouring reachable values	—
Prothrombin time (%)	%	computed value: interval to the neighbouring reachable values	—

Counts with an unknown rule¶

Variable	Unit	Resolution	Model study
ICU days	days	whole days, counting rule unknown (±1)	—

Age¶

Variable	Unit	Resolution	Model study
Age	years	completed years; tenths for infants; top-coded	—

Rule sets¶

Variable	Unit	Resolution	Model study
Intraoperative colloid	mL	—	—

Exact¶

Variable	Unit	Resolution	Model study
Calcium chloride	mg	exact	—
Ephedrine	mg	exact	—
Fentanyl	mcg	exact	—
Intraoperative FFP transfusion	Unit	exact	—
Intraoperative RBC transfusion	Unit	exact	—
Phenylephrine	mcg	exact	—
Recording Start Time	sec	exact	—
Rocuronium	mg	exact	—

Categories (no numeric value)¶

Variable	Unit	Resolution	Model study
ASA Physical status classification		—	—
Airway route		—	—
Anesthesia type		—	—
Cormack's grade		—	—
Diagnosis		—	—
Double lumen tube size	Fr	—	—
Emergency operation		—	—
Endotracheal tube size	mm	—	—
In-hospital Mortality		—	—
LMA size		—	—
Operation name		—	—
Preoperative ECG		—	—
Preoperative diabetes		—	—
Preoperative hypertension		—	—
Preoperative pulmonary function		—	—
Sex	M/F	—	—
Site of IV line (1)		—	—
Site of IV line (2)		—	—
Site of arterial line (1)		—	—
Site of arterial line (2)		—	—
Site of central line (1)		—	—
Site of central line (2)		—	—
Surgery type		—	—
Surgical approach		—	—
Surgical department		—	—
Surgical position		—	—