Lead author | Year | Total number of cervical cytology smears | Number of unsatisfactory smears | Percentage of unsatisfactory smears | Location of study |
Colgan et al8 | 2004 | 352 680 | 915 | 0.3 | Canada |
Zhao et al9 | 2011 | 972 | 2 | 0.2 | China |
Kirscher et al10 | 2006 | 84 414 | 292 | 0.3 | Denmark |
Beerman et al11 | 2008 | 35 315 | 46 | 0.1 | the Netherlands |
Sykes et al12 | 2008 | 451 | 12 | 2.7 | New Zealand |
Sykes et al12 | 2008 | 457 | 12 | 2.6 | New Zealand |
Kitchener et al13 | 2011 | 22 145 | 354 | 1.6 | UK |
Narine and Young14 | 2007 | 53 982 | 208 | 0.4 | UK |
Narine and Young14 | Unpublished | 27 738 | 327 | 1.2 | UK |
Alsharif et al15 | 2009 | 232 022 | 360 | 0.2 | USA |
Stark16 | 2007 | 137 703 | 302 | 0.2 | USA |
Nance17 | 2007 | 92 875 | 158 | 0.2 | USA |
Fremont-Smith et al18 | 2004 | 58 580 | 130 | 0.2 | USA |
Sass19 | 2003 | 8771 | 14 | 0.2 | USA |
Wilbur et al20 | 2009 | 12 313 | 27 | 0.2 | USA |
Total | 1 120 418 | 3159 | 0.3 |