Table 1.

Demographic Characteristics of Patients Enrolled in Program (N = 500)

Characteristic	Value
Age, mean (median); range, y	55 (57); 23–88
Sex, % women/men	34/66
Previous stone composition,a no. of patients
Calcium oxalate	315
Unknown composition	102
Urate	54
Calcium phosphate	25
Pure apatite	2
Pure brushite	2
Average no. of previous stone events	2.8
Enrollment period, mo	17
Mean follow-up, d	267

^aStone analysis data obtained from Quest Diagnostics (San Juan Capistrano, CA).