8. Analysis techniques
Where reports authored by ScotCen Social Research discuss differences between two percentages (either across time, or between two different groups of people within a single year), this difference is significant at the 95% level or above, unless otherwise stated. Differences between two years are tested using standard z-tests, taking account of complex standard errors arising from the sample design. Differences between groups within a given year are tested using logistic regression analysis, which shows the factors and categories that are significantly (and independently) related to the dependent variable. Analysis is carried out in IBM SPSS Statistics v.25, using the CS logistic function to take account of the sample design in calculations.