What's wrong with correlative experiments?

Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature Cell Biology (Impact Factor: 19.68). 09/2011; 13(9):1011. DOI: 10.1038/ncb2325
Source: PubMed


Here, we make a case for multivariate measurements in cell biology with minimal perturbation. We discuss how correlative data can identify cause-effect relationships in cellular pathways with potentially greater accuracy than conventional perturbation studies.

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    • "The extension of correlative analyses to delineate causal influence marks a significant advance. As noted in a recent commentary, the majority of analyses in cell biology are correlative, with the analysis of causation remaining infrequent [15]. This is particularly true at a systemic level where complex patterns of inter-feature causation are considered. "
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    • "Rigorous correlation analyses of cell images will certainly help [Vilela and Danuser, 2011] but may not be enough by itself. We believe that the combination of quantitative image analysis with modeling and controlled perturbations of the signaling molecules, such as by photoactivation [Ghosh et al., 2004; Wu et al., 2009] promises to reveal many clues on these interdependencies. "
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