And then what would be the advantages and disadvantages of such a study design for scoring and interpretation purposes?

Well, it seems to me that there are different ideas floating around of how concurrent controls might be eliminated from a study, so I think, I think it may depend upon the specific way this would be implemented in practice.

Um, yes, if there's no controls of any sort, then by definition, all scoring would have to be conducted using an absolute approach.

And I can't even visualize how that would work for types of findings that typically require a relative approach, sus- such as the scoring of a splenic hematopoiesis in rodents On the other hand, if someone was to create a virtual set of control an-animal images to be used as comparators, then a relative scoring approach could be used in that case.

Overall, I'm not a big fan of the idea.

I feel that concurrent control group is an essential comparator for most studies, if not always for severity scoring, then at the very least for data interpretation once the findings have all been recorded.

Because each set of study controls can be as different as a fingerprint, and certain sets of controls may be outliers compared to the norm, I suspect that comparing the results from treated animals to some sort of computer-generated average or range has the potential to generate false positive and false negative findings.

Mm.