Table 3. Effects of sex-by-age category (16–45 years vs. 56–80 years) interaction on ranked coefficients of variation (CV = σ/μ) calculated from original paired 24-h urinary solutes (urinary ammonium (NH₃), calcium (Ca), chloride (Cl), citrate (Cit), potassium (K), magnesium (Mg), sodium (Na), oxalate (Ox), phosphorus (P), sulfate (SO₄), uric acid (UA), urine urea nitrogen (UN)) collected from 6,758 female and 9,024 male stone-formers aged 16–80 at the False Discovery Rate [Verhoeven, 2005 #22836].

Trait	F	Pnom	r 2
Ca	1.70	0.1920	0.0682
Cit	29.2	<0.0001**	0.0293
Cl	1.97	0.1601	0.108
Cr	1.98	0.1590	7.65×10−4
K	5.34	0.0208	0.0521
Mg	3.83	0.0503	0.0307
Na	0.18	0.6728	0.111
NH4	0.43	0.5116	0.0225
Ox	0.02	0.8932	0.0342
P	0.28	0.5924	0.0678
SO4	0.55	0.4574	0.0354
UA	0.04	0.8466	0.0941
UN	0.11	0.7389	0.0988