New anthropometry-based age- and sex-specific reference values for urinary 24-hour creatinine excretion based on the adult Swiss population

Table 3 Adequacy of the 24-hour urinary collection using the current reference values and the new prediction model, in the whole SKIPOGH population and in the elderly patients

Classification according to current reference values	Classification according to the new prediction model ^a			Percentage of reclassified samples
	Incomplete	Adequate	Overcollected
	(<10th centile)	(10th to 90th cent)	(>90th centile)
Whole population				44.2%
Incomplete	57	247	1^b
Adequate	1	406	10
Overcollected	0	180	92
Older population (age >60 years)				59.9%
Incomplete	8	141	1^b
Adequate	0	84	10
Overcollected	0	2	11

^aThe selection of 10th to 90th as cut-off is arbitrary and should be interpreted as an example of application of the prediction equation; ^bthis observation is from a 90-year-old woman with 24-hour urinary creatinine of 132 μmol/kg/24 hours and BMI 23.8 kg/m². Values represent number of people. Current reference values for adequate 24-hour urinary collection: 177 to 221 μmol/kg (20 to 25 mg/kg) in men and 133 to 177 μmol/kg (15 to 20 mg/kg) in women.

ISSN: 1741-7015