Figure 3.

Different data integration strategies. (a) illustrates early integration where data is combined into a single data matrix before modeling. (b) depicts the intermediate data integration level where data matrices are transformed or mapped into a common meaningful representation before modeling. In (c), each data model is generated separately and is then combined with models based on other data types to generate the integrative or high-level model. Early integration is often used in meta-analysis [76]. Intermediate and late data integration strategies can be applied for meta-analysis but such applications are scarce in the literature.