The hard palate is a thin horizontal bony plate of the skull, located in the roof of the mouth.
Defining Variables. Variables can be defined as any aspect of a theory that can vary or change as part of the interaction within the theory. In other words, variables are anything can effect or change the results of a study. Every study has variables as these are needed in order to understand differences.here is no limit to the number of variables that can be measured, although the more variables, the more complex the study and the more complex the statistical analysis. The most powerful benefit of increasing our variables, however, is control.
Bias: A systematic error in the design, recruitment, data collection or analysis that results in a mistaken estimation of the true effect of the exposure and the outcome. Confounding: A situation in which the effect or association between an exposure and outcome is distorted by the presence of another variable. Positive confounding (when the observed association is biased away from the null) and negative confounding (when the observed association is biased toward the null) both occur. Confounder: an extraneous variable that wholly or partially accounts for the observed effect of a risk factor on disease status..