Table 2.

The spike experiment in various hair samples to determine the recovery of hair samples spiked with cortisol prior to digestion

Hair sample weight range	Concentration range in unspiked hair samples	Spike amount	Observed spike amount	Spike recovery
7.8–12.2 mg	4.66–6.59 pg/mg	14 pg	14–20 pg	97–137%
6.4–17.2 mg	0.90–8.14 pg/mg	57 pg	58–65 pg	101–115%
7.2–16.6 mg	0.90–8.14 pg/mg	144 pg	142–159 pg	99–111%