HPFitis
HPFitis is use of HPF (high-power field) without proper qualification, i.e. without giving the field area.
HPF redirects here.
Etiology
Its etiology is thought to be either:
- Ignorance of statistics and sampling theory.
- Laziness.
- A combination of the above two.
It appears to have a higher incidence in math phobic individuals.
Consequences of HPFitis
- Papers on eosinophilic esophagitis are not comparable.[1]
- GISTs were improperly staged - until they standardized to 5 mm2.
- Mitotic score in the Nottingham score for invasive breast cancer is based on the pseudo-standard area of "10 HPFs"; this results in significant variance due to the field area of the microscope in large cohorts.[2]
Field area
Most modern microscopes, have an eye piece diameter of 22 mm. Therefore, the field diameter at 40 X is approximately 22 mm / 40 X ~= 0.55 mm and the field of view is pi/4*(0.55 mm)2 = 0.2376 mm2.
See also
References
- ↑ Dellon ES, Aderoju A, Woosley JT, Sandler RS, Shaheen NJ (October 2007). "Variability in diagnostic criteria for eosinophilic esophagitis: a systematic review". Am. J. Gastroenterol. 102 (10): 2300–13. doi:10.1111/j.1572-0241.2007.01396.x. PMID 17617209.
- ↑ Bonert, M.; Tate, AJ. (Feb 2017). "Mitotic counts in breast cancer should be standardized with a uniform sample area.". Biomed Eng Online 16 (1): 28. doi:10.1186/s12938-016-0301-z. PMC 5312435. PMID 28202066. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312435/.