Statistical analysis
The patients were grouped into two groups randomly; one using trans-nasal approach and the other using the trans-oral approach. Both groups were compared for all demographic variables as well as clinic-pathologic variables.
The primary outcome of this study is to compare the diagnostic accuracy of both trans-oral and trans-nasal approaches of taking a biopsy. The secondary outcome variables were the safety, tolerance and how easy is each approach. Also, evaluation of visualization approaches and methods of anesthesia were among the secondary outcome variables.
Recorded data were coded, entered, cleaned, and analyzed using the statistical package for social sciences, version 25.0 (SPSS Inc., Chicago, Illinois, USA). Quantitative data were expressed as mean± standard deviation (SD). Qualitative data were expressed as frequency and percentage. Chi-square (x2) test of significance was used in order to compare proportions between two qualitative parameters, and the student t-test was used for the numerical parametric data. The confidence level was set to 95% and the margin of error accepted was set to 5%. So, the p-value was considered significant if< 0.05. The Cohen kappa index for agreement was calculated to evaluate agreement between methods of biopsies. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the two different approaches of office-based based biopsy were calculated.
Results
Ninety-nine patients were invited to participate in the study; 35 refused to participate, 14 were ineligible; thus, 60 enrolled to the study signed a consent form and randomized into two groups: 30 trans-nasal group and 30 trans-oral group.