Related Experiment Video
Updated: Feb 22, 2026

Observational Study Protocol for Repeated Clinical Examination and Critical Care Ultrasonography Within the Simple Intensive Care Studies
Published on: January 16, 2019
Reference intervals for serum bilirubin, urea, and uric acid in healthy Chinese geriatric population
Yuanqing Yang1, Hongmin Jiang1, Aiguo Tang1
1Department of Laboratory Medcine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
Objectives:
The study aims to establish the reference intervals (RIs) for total bilirubin (TBIL), direct bilirubin (DBIL), urea (UR), and uric acid (UA) in healthy Chinese geriatric population.
Methods:
Eight hundred and twenty cases from six representative geographical regions in China (including male 413 cases and female 407 cases) of apparently healthy individuals aged 60-96 years were recruited. Serum TBIL, DBIL, UR, and UA were analyzed by automatic biochemical analyzer and RIs were determined following CLSI C28-A3 guidelines using a non-parametric method.
Results:
In apparently healthy Chinese geriatric population of China, the RIs of TBIL, DBIL, UR, and UA were 6.6~21.8 μmol/L, 1.9~8.0 μmol/L, 3.60~9.51 mmol/L, 179.2~460.9 μmol/L in males and 6.1~20.0 μmol/L, 1.8~7.1 μmol/L,3.35~8.89 mmol/L, 130.2~443.4 μmol/L in females, respectively.
Conclusions:
The RIs of TBIL, DBIL, UR, and UA were established within apparently healthy geriatric Chinese population according to CLSIC28-A3 document, providing a reference for the clinical.
Related Concept Videos
Serum Studies: Renal Function Tests
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Excretion
Drug Dosing in Renal Diseases: Measurement of Serum Creatinine Concentration and Clearance
Drug Dosing in Renal Diseases: Estimation of Glomerular Filtration Rate Based on Serum Creatinine Concentration
Drug Dosing in Renal Diseases: Measurement of Glomerular Filtration Rate
Factors Affecting Renal Clearance: Renal Impairment
One condition associated with renal failure is uremia. Uremia is characterized by impaired glomerular filtration and fluid accumulation in the body. This condition hinders the renal clearance of drugs, resulting in drug accumulation and potential...

