Figures & data
Figure 1 Number of citations per year for PubMed search for the multimorbidity search string (dark blue) in comparison to number of citations added (light blue).
Figure 2 A comorbid condition may 1) cause, 2) be correlated without causality, 3) be caused by, or 4) have no causal relationship and no (or weak) correlation with a condition of interest in cost of illness studies.
