Lillås BS, et al. - In this study of various outpatient procedures, 14 healthy candidates were involved (six males and eight females) in order to examine the use of iohexol clearance to measure the renal functional response (RFR) in outpatients using both one- and two-sample methods. The three distinct protein loads led to comparable mean RFR although there was significant intra-individual variability. One- and two-sample methods for measurement of RFR explicated comparable results with near-identical means, however, there was some intra-individual variation that was comparable for various protein loads. Thus, RFR could be examined using plasma iohexol clearance in an outpatient setting. A mean RFR of about 12% was exhibited by protocols using commercially available protein supplementation. Moreover, one- and two-sample methods for measuring RFR yield comparable results.