The document discusses various methods for evaluating renal function and structure, including urinalysis, tests of glomerular function like GFR and protein excretion, tests of renal tubular function, imaging procedures like ultrasound and radionuclide scanning, renal biopsy, and the limitations of renal function at birth. Urinalysis provides a non-invasive indicator of renal function while tests of glomerular and tubular function assess filtration, concentration, dilution and acidification abilities. Imaging can evaluate kidney size, shape, blood flow and reflux while biopsy offers definitive histological diagnosis. Renal function is significantly limited at birth with low GFR and impaired concentration, sodium handling and acid-base regulation.