Endoscopic ultrasound has emerged as a promising diagnostic modality for locoregional staging of rectal cancer.
However, as with any new technology, publication bias, the selective reporting of studies featuring positive results, may result in overestimation of the capability of endoscopic ultrasound.
Dr Gavin Harewood from Minnesota systematically assessed for publication bias in the reporting of the accuracy of endoscopic ultrasound in staging rectal cancer.
The investigator performed a MEDLINE search for all published estimates of endoscopic ultrasound accuracy in staging rectal cancer between 1985 and 2003.
All retrieved studies were fully published in the English literature.
The researcher analyzed published studies and abstracted information on the accuracy of endoscopic ultrasound, year of publication, number of subjects studied, impact factor of journal, and type of journal.
In total, the investigator reviewed 202 abstracts of which 41 publications met the stated criteria for inclusion.
|T- and N-staging accuracy rates declined over time with the lowest rates reported in more recent literature|
|American Journal of Gastroenterology|
The researcher noted that endoscopic ultrasound T-staging accuracy was reported in 40 studies while N-staging accuracy was reported in 27 studies.
The experience of 4118 subjects was reported with an overall mean T-staging accuracy of 85% and N-staging accuracy of 75%.
The investigator reported a paucity of smaller studies expressing low endoscopic ultrasound accuracy rates.
Both T-staging and N-staging accuracy rates also declined over time with the lowest rates reported in more recent literature.
Dr Harewood concludes, “The performance of endoscopic ultrasound in staging rectal cancer may be overestimated in the literature due to publication bias.”
“This inflated estimate of the capability of endoscopic ultrasound may lead to unrealistic expectations of this technology.”