Creatinine clearance is a test used to assess renal function(glomerular filtration rate-GFR)) and also for staging chronic kidney disease (CKD) . Urine creatinine estimation requires collection of 24h urine which is a cumbersome and tedious process. Our study proposes a unique fractional urine collection method for urine creatinine estimation that would entail collection of small volumes of urine each time patient voids over 24h period and then compare this new method with conventional 24hour collection method.