From rat tendon to human claim: reading preclinical healing studies

Much of what circulates about "healing peptides" rests on cell culture and rodent injury models. Those studies can be well done and still say little about people. Questions worth asking of any such paper:

• Model: which species, which injury, induced how? A surgically transected rat tendon is not a chronic human tendinopathy.
• Blinding and randomisation: were outcome assessors blinded, and were animals randomly allocated? ARRIVE 2.0 treats these as essential items.
• Outcome: histology scores and biomechanics in animals are surrogates, not pain or function in people.
• Independence: how many labs have reported the effect? Results that come from a single group need independent replication.
• Human data: is there any registered human trial, and was it published?

Translation is the norm to question, not to assume. Hackam and Redelmeier found that only about a third of highly cited animal studies were later replicated in human randomised trials. Begley and Ellis reported that most of the "landmark" preclinical cancer findings they tried to reproduce could not be confirmed.

Post a preclinical paper you think is unusually strong or unusually weak, and explain why using the points above.

Sources

1. Percie du Sert N, Hurst V, Ahluwalia A, et al. The ARRIVE guidelines 2.0: updated guidelines for reporting animal research. PLoS Biol 2020;18(7):e3000410. doi:10.1371/journal.pbio.3000410
2. Hackam DG, Redelmeier DA. Translation of research evidence from animals to humans. JAMA 2006;296(14):1731–1732. doi:10.1001/jama.296.14.1731
3. Begley CG, Ellis LM. Raise standards for preclinical cancer research. Nature 2012;483:531–533. doi:10.1038/483531a