Urine samples

Type of urine sample             How it is used
First morning sample               Provides a concentrated sample of urine that contains the overnight
                                                 accumulation of metabolites. Useful for detection of proteins or
                                                 unusual analytes.
Random                                   Convenient sample that can be collected at any time.
                                                 Most often used for routine screening tests.
Timed                                       Typically 2 to 6 hours of urine output is collected to give a
                                                 representative sample; duration of collection depends on the
                                                 analytes.
24-hour                                    Entire urine output for a 24-hour period is collected. Like a timed
                                                 urine, but used for metabolites whose excretion rates may vary with
                                                 time of day and full 24-hour collection is needed to be representative.