Two by two hour creatinine clearance--repeatable and valid.

S Herget-Rosenthal; A Kribben; F Pietruck; B Ross; T Philipp

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PubMed · 10404695

Two by two hour creatinine clearance--repeatable and valid.

S Herget-Rosenthal·A Kribben·F Pietruck·B Ross·T Philipp

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Abstract

AIM: The purpose of this study was to determine the repeatability and validity of 2 x 2 hour creatinine clearance, and the validity of creatinine clearances estimated by equations. PATIENTS AND METHODS: In 30 patients two 2 x 2 h and two 24-h creatinine clearances were performed on consecutive days. In addition, creatinine clearances estimated by 4 different equations were calculated. Two by two hour creatinine clearance provided a measurement of GFR as valid as 24-h creatinine clearance. RESULTS: We found, that 2 x 2 h creatinine clearance was well repeatable with a mean difference between 2 repeated measurements of 0.8 ml/min and low coefficients of repeatability of 14.5 ml/min. The validity of 2 x 2 h creatinine clearance, assessed by the mean difference between 2 x 2 and 24-h creatinine clearances, was 1.2 ml/min with tight 95% limits of agreement with a range from -8.1 to 10.5 ml/min. This high degree of repeatability and validity was present over the entire range of renal function (6-141 ml/min). As 2 x 2 h creatinine clearance is more simple and rapid than 24-h creatinine clearance, results are obtained on the same day and easy, but repeatable and valid day-to-day monitoring of renal function is possible. In addition, the two times two hour clearances allow for quality control. In contrast, estimated creatinine clearances show only poor validity. CONCLUSION: Because of the high degree of repeatability and validity, 2 x 2 h creatinine clearance may replace 24-h creatinine clearance as the standard method to determine renal function in clinical practice.

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Adolescent Adult Aged Creatinine Female Glomerular Filtration Rate Humans Male Metabolic Clearance Rate Methods Middle Aged Models, Theoretical Reproducibility of Results Journal Article

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S Herget-Rosenthal, A Kribben, F Pietruck, B Ross, T Philipp. 1999. Two by two hour creatinine clearance--repeatable and valid.. https://pubmed.ncbi.nlm.nih.gov/10404695/

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