To determine whether urine color, as measured by a color chart, might be a valid indicator of hydration status in frail nursing home residents, this study tested the associations between urine color and urine specific gravity. This is a descriptive correlational study set in seven nursing homes in eastern Iowa. Ninety-eight nursing home residents > or =65 years of age participated. Exclusion criteria for the study included: unstable congestive heart failure or diabetes, documented renal disease, hyponatremia (serum sodium <135 meq/L), terminal illness, acutely confused/delirious or urinary tract infection at baseline, and gastrostomy-tube dependence. Weekly urine specimens were collected. Ucol was measured first, using a urine color chart. Usg was determined using the Chemstrip Mini UA Urine Analyzer. Week-by-week Spearman rank order correlations between urine color and specific gravity for the total sample (n=98) ranged from r(s) = 0.3 - 0.7, p < .01; the PROC mixed model was significant, p < .01. In subgroup analyses (n=78), all females (r(s) = 0.67, p = .01) and both males (r(s) = 0.53, p = .01) and females (r(s) = 0.72, p =.01) with adequate renal function (Cockcroft-Gault estimated creatinine clearance [CrCl] values of > or =50 ml/min) had significant associations between average urine color and average Usg. Females with mild renal impairment (CrCl between 30 and 50 ml/min) also had significant associations between Ucol and Usg (r(s) = .64, p < .01). Ucol averaged over several individual readings offers another tool in assessing hydration status in Caucasian nursing home residents with adequate renal function measures by estimated CrCl values. PMID: 16552947 [PubMed - indexed for MEDLINE