Associations between clinical variables and ASPM or microcephalin proteins in the primary cultures were undertaken using Fisher's Exact test for categorical variables (site, disease stage, grade and morphology at presentation) and the non-parametric Kruskall Wallis and Wilcoxon Mann–Whitney test for continuous variables.
The categorical variables included site, gender, complications and operator experience level.
We tested for correlation between cytokine responses and various site categorical variables such as urban rural, military civilian, and road surface open land.
There were four categorical covariates: AGP site, gender, best estimate IQ (in three categories, <50, 50 69, and ≥70), and verbal/nonverbal status (in three categories, verbal, nonverbal with ≥5 words, and nonverbal with <5 words).
The model included the fixed categorical effects of site, treatment, week, age group, treatment-by-week interaction, age group-by-week interaction, treatment-by-age group interaction, treatment-by-age-group-by-week interaction, as well as the continuous fixed covariates of baseline score and baseline-by-week interaction.
Comparison of categorical variables between sites of presentation (ED, general practice, pharmacy) was undertaken using χ tests or Fisher's exact test where required.
The 300 Index model used 15 continuous variables and 12 categorical variables while the Site Index model used 13 continuous variables and 6 categorical variables.
Kruskal Wallis and Pearson χ tests were used to compare continuous and categorical variables respectively by site and outcome.
Independent variables included the fixed, categorical effects of investigative site, treatment, time, and the treatment-by-time interaction, along with the continuous covariates of baseline severity and the baseline severity by time interaction.
