| Authors/SBO frequencies | Table Column Head | ||
| Number | Pour cent | p-value | |
| Arnold et al., France 2003 [11] | 131 | 32.00 | <0.001 |
| Mehmet U. et al., Maroc 2012 [13] | 128 | 67.02 | 0.25 |
| Kurem R.T. et al., Pakistan 2014 [12] | 102 | 54.55 | 0.24 |
| Our study | 114 | 74.03 |
|