2.13. Statistical analysis
For the demographic and clinical categorical data (gender and tobacco use), the differences between the controls and cannabis users were assessed with a two-tailed chi-squared test. Protein-related statistics were obtained with Progenesis LC-MS (Waters, USA) and the IPA software (QIAGEN, Germany) while functional-related statistical analysis was performed with GraphPad Prism 5 software (GraphPad Software, USA). For functional assays, the difference between the control and cannabis users was assessed using the Student´s t-test (unpaired, two-tailed) after a normal distribution was evaluated with a Kolmogorov-Smirnov test. Correlations were performed using a Pearson’s test to evaluate the association between every neuropsychological test score, and the THC-COOH and 11-OH-THC plasma levels. The data were presented as means ± SEM and the differences were considered statistically significant at a p value < 0.05.