9) Beside the comparison of means, the MAST score was transformed into a categoric variable
We controlled for it by including it in the model as a categoric variable
, since the association was not a linear one.
Race/ethnicity constitutes a categoric variable
representing the racial or Hispanic ethnicity of the respondent: Hispanic/Latino, black/African American, Asian/Pacific Islander, Native American/Alaskan native, white, other race/ethnicity, or missing race/ethnicity.
Since this was a categoric variable
for which dummies were created, two variable states (high and low) are shown.
There are six categoric variables
and one, annual personal income, in continuous form.
were compared using the chi-square test or Fisher exact test when appropriate.
The quantitative variables were expressed as mean [+ or -] standard deviation and categoric variables
as number of cases (%).
Pearson's Chi Square test or Fisher's exact test is used to study categoric variables
and unpaired 't' test is used for studying continuous variables.
The relationships between gene mutation status and the clinicopathologic features were analyzed using the [chi square] test and Fisher exact test for categoric variables
, and the Wilcoxon rank sum test for continuous variables.
The groups were compared using Student's t-test for numeric variables and Chi-square test for categoric variables
Oil shocks provide another set of categoric variables
, with inputs of a series of zeros except for ones in 1974 and 1975, 1979 and 1980--the main years for economic impacts from shortages and price increases in energy (see Baily, 1981, and Fischer, 1996, for effects of fuel inflation on business and on society).