title: Urinary creatinine is unsuitable as reference value for collagen metabolite output.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D003094:Collagen / Q000378:metabolism*; D003404:Creatinine / Q000652:urine*; D005069:Evaluation Studies as Topic; D006801:Humans; D008722:Methods; D008875:Middle Aged
chemical_list: D003094:Collagen; D003404:Creatinine