Also, because the variables in the CCHS are self-reported, there is a potential for recall bias or social desirability bias.
A multiple linear regression model is shown in Eq. (1), and its least-squares solution is given by Eq. (2), where XTX is singular because of the variables in X exceeds the number of observations or the collinearities.
Because the dependent variable in the regression is a nonnegative count variable with no theoretical upper bound it takes on integer values greater than or equal to zero the most appropriate econometric model for the analysis conducted in this paper is the fixed effects (FE) Poisson regression model developed by Hausman, Hall, and Griliches (Hausman et al. 1984).
Because the independent variable in the statistical model was change in frequency of intercourse (postoperative frequency minus preoperative frequency) and not the magnitude of intercourse frequency, this disparity in the preoperative characteristics does not adversely impact our findings.
Because the dependent variable in the current study represented a summation of CM incidence due to many different ecological systems (webs of causation), our ability to accurately predict crude herd-level rate is understandably low.
Because most of the variables in the dataset were not normally distributed, all correlations were presented with Spearman's rho correlation.
Rectal findings were not used as a variable in the analysis because the variable was essential in the classification of surgically and medically treated cases.
The model used here is an approximate of the hazard rate because the dependent variable in our model is not hazard rate but odds ratios, which are function of time and other variables.
Because the variable of interest in our study is health status (i.e. migraine), it is possible that any differences that may have been caused by nonresponse may not have a great effect (40).
This may be because the dependent variable in this study—a composite measure of care quality referred specifically to the last delivery, and thus prior parity played a lesser role in the respondents' rating.
