Page 49 - PATIENT REGISTRY DATA FOR RESEARCH: A Basic Practical Guide
P. 49

During statistical analysis


                   e.     For a descriptive study (using census data) with no missing values, it is still

                          acceptable to provide just a descriptive statistical analysis of the registry data


                          alone, which means that no inferential statistical analysis will be conducted.

                   f.     However, if there are missing values in the data set, then it will become necessary

                          to conduct both descriptive and inferential statistical analysis of the data set since


                          it will now be necessary to infer these findings about the target population from

                          the sample data.


                   g.     It is important to observe and take proactive steps to ensure that a list of

                          underlying assumptions which must hold true in order for all the statistical


                          computations to be valid, especially with regard to parametric test and regression

                          modelling. This is because it will be a futile attempt to conduct statistical analysis


                          by performing all statistical computations and yet violating these underlying

                          statistical assumptions (or failing to ensure that these assumptions actually hold


                          true), as this will yield invalid conclusions.

                   h.     Conducting inferential statistical analysis on patient registry data (such as the use

                          of disease modelling methods as research tools) can be a very complicated task


                          because these patient registries can have many dozens of variables which are

                          regarded as the independent variables for a measurable outcome. It will not be


                          possible to label all these variables as risk factors in a single analysis by using a

                          multivariate model because such an analysis will not be efficient due to issues


                          which have arisen from not being able to (i) fulfil all the assumptions in regression

                          modelling and also to (ii) meet the minimum sample size requirements. Therefore,

                          it is strongly recommended for the researcher to carefully select a list of


                          independent variables that qualify to be regarded as risk factors to be tested in the
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