en.wikipedia.org/w/index.php?title=Reproducibility&diff=prev&oldid=1369013626
3 corrections found
A Phase I discovery will be followed by Phase II reproductions as a drug develops towards commercial production.
This misstates what Phase I and Phase II mean in drug development. Phase I trials assess safety and dosing; Phase II trials test whether a treatment works and continue safety evaluation.
Full reasoning
In FDA and National Cancer Institute definitions, Phase I and Phase II are stages of clinical trials, not labels for a “discovery” followed by “reproductions.”
- The FDA explains that Phase 1 is the initial introduction of an investigational drug into humans.
- The National Cancer Institute says phase 1 trials determine whether a treatment is safe, what its side effects are, and the highest dose people can tolerate.
- NCI also says phase 2 trials include more people to see whether the treatment seems to work, while continuing to study safety.
Because those are the standard meanings of Phase I and Phase II in drug development, describing them as a “discovery” and then “reproductions” is incorrect.
2 sources
- Drug Development and Review Definitions | FDA
As defined in 21 CFR 312.21, a Phase 1 clinical trial includes the initial introduction of an investigational new drug into humans.
- How Do Clinical Trials Work? - NCI
In a phase 1 clinical trial, researchers figure out whether a new treatment is safe... A phase 2 clinical trial includes more people ... to see if the new treatment seems to work against the cancer.
Then, the standard deviation of the difference between two values obtained within the same laboratory is called repeatability. The standard deviation for the difference between two measurement from different laboratories is called reproducibility.
This mixes up repeatability/reproducibility with differences between two results. Standard metrology references define them using the dispersion or standard deviation of results under repeatability or reproducibility conditions, not as the standard deviation of a two-result difference.
Full reasoning
Standard metrology references do not define repeatability and reproducibility as “the standard deviation of the difference between two values.”
NIST defines repeatability as the closeness of agreement between successive measurements under the same conditions, and says it may be expressed quantitatively using the dispersion characteristics of the results. It defines reproducibility similarly under changed conditions. Separately, NIST’s interlaboratory guidance defines the repeatability standard deviation as the pooled within-laboratory standard deviation, and the reproducibility standard deviation as an interlaboratory variability measure.
That matters because the difference between two results is a related but different quantity. Metrology standards typically reserve separate terms such as repeatability limit/coefficient or reproducibility limit for bounds on differences between two measurements. So the article is conflating the underlying standard deviations with the two-result difference measure.
3 sources
- NIST TN 1297: Appendix D1. Terminology | NIST
Repeatability ... may be expressed quantitatively in terms of the dispersion characteristics of the results. Reproducibility ... may be expressed quantitatively in terms of the dispersion characteristics of the results.
- Reproducibility Standard Deviation | NIST
The reproducibility standard deviation is computed as ... with s_r denoting the repeatability standard deviation ... and s_i denoting ... the standard deviation of the i-th laboratory.
- Repeatability and level-2 standard deviations | NIST
The repeatability standard deviation of the instrument can be computed in two ways. It can be computed as the residual standard deviation from the design ...
Nobody else has been able to produce this result.
This is outdated. Treponema pallidum, the bacterium that causes syphilis, has since been cultured in vitro by other researchers.
Full reasoning
The sentence is incorrect in the present tense. Although long-term cultivation of Treponema pallidum was historically a major challenge, later work did succeed in culturing the syphilis bacterium in vitro.
A 2018 mBio paper reported the first consistent long-term in vitro cultivation of T. pallidum subsp. pallidum. A later PubMed-indexed review states that long-term in vitro cultivation of T. pallidum was first achieved in 2017 and reported in 2018. That directly contradicts the article’s absolute claim that “nobody else has been able to produce this result.”
So even if Noguchi’s original claim was controversial historically, the blanket present-day statement that no one else has achieved such a result is false.
2 sources
- Long-Term In Vitro Culture of the Syphilis Spirochete Treponema pallidum subsp. pallidum | mBio
Here, we report the first consistent long-term in vitro cultivation of T. pallidum subsp. pallidum.
- In Vitro Cultivation of the Syphilis Spirochete Treponema pallidum - PubMed
For over a century, investigation of Treponema pallidum ... was hindered by an inability to culture the organism in vitro ... Long-term in vitro cultivation of T. pallidum was first achieved in 2017 (Edmondson, Hu, & Norris, 2018).