Daily average concentration (DAC) A paired t -test run on the residents with measures both pre- and post-intervention (n = 16) showed a marginally non-significant effect, with pre-intervention concentrations (3.01 nmol L −1 ± 0.51) lower than post-intervention ones (4.51 ± 0.59), t(15) = 1.99, p = 0.065.
It should also be noted that although our data showed a positive trend between the garden intervention and i. perceived stress, ii. cortisol profiles that relate to less stress and iii. improvements in mood (trends not found in our control population), sample sizes were small, and we cannot categorically claim ‘cause and effect’; other factors external to the project could also have been influencing these trends.