Table 1. Characteristics of the included studies in the meta-analysis.
| Author and year | Continent | Sample size | Population | ROB | Prevalence |
|---|---|---|---|---|---|
| Osborn et al. 1990 | NA | 385 | Dentists | Low | 68.31 |
| Rundcrantz et al. (a) 1990 | Eu | 311 | DA | Low | 83.28 |
| Rundcrantz et al. (b) 1991 | Eu | 311 | Dentists | Low | 84.24 |
| Marshall et al. 1997 | Au | 355 | Dentists | Low | 81.97 |
| Akesson et al. 1999 | Eu | 74 | ALL | Low | 91.89 |
| Kerosuo et al. 2000 | Eu | 228 | Dentists | Low | 70.61 |
| Lalumandier et al. 2001 | NA | 5119 | ALL | Low | 47.14 |
| Anton et al. 2002 | NA | 95 | DA | Low | 92.63 |
| Szymanska 2002 | Eu | 268 | Dentists | Low | 91.42 |
| Tezel et al. 2005 | Asia | 221 | DS | Low | 85.97 |
| Leggat et al. 2006 | Au | 285 | Dentists | Low | 87.37 |
| Polat et al. 2007 | Asia | 120 | Dentists | Low | 94.17 |
| Puriene et al. 2008 | Eu | 1670 | Dentists | Low | 86.53 |
| de Carvalho et al. 2009 | SA | 227 | DS | Low | 70.93 |
| Akar et al. 2009 | Asia | 185 | DA | Low | 23.78 |
| Ayers et al. 2009 | Au | 560 | Dentists | Low | 59.82 |
| Dajpratham et al. 2010 | Asia | 163 | ALL | Low | 96.93 |
| Kierklo et al. 2011 | Eu | 220 | Dentists | Low | 90.00 |
| Ellapen et al 2011 | Africa | 94 | Dentists | Low | 54.26 |
| Moradia and Prakash 2011 | Asia | 77 | ALL | Low | 63.64 |
| Sankar et al. 2012 | Asia | 259 | Dentists | Low | 41.70 |
| Tzu et al. 2012 | Asia | 197 | Dentists | Low | 92.39 |
| Muralidharan et al. 2013 | Asia | 73 | Dentists | Low | 78.08 |
| Kumar et al. 2013 | Asia | 536 | Dentists | Low | 100.00 |
| Vuletic et al. 2013 | Eu | 89 | Dentists | Low | 69.66 |
| Kazancioglu et al. 2013 | Asia | 608 | Dentists | Low | 87.01 |
| Rafeemanesh et al. 2013 | Asia | 58 | Dentists | Low | 82.76 |
| Zoidaki et al. 2013 | Eu | 80 | Dentists | Low | 82.50 |
| Movahhed et al. 2013 | Asia | 177 | DS | Low | 83.62 |
| Sustova et al. 2013 | Eu | 182 | DS | Low | 39.01 |
| Vora et al. 2014 | Asia | 86 | Dentists | Low | 62.79 |
| Zarra and Lambrianidis 2014 | Eu | 120 | Dentists | Low | 60.83 |
| Mendegeri et al. 2014 | Asia | 60 | Dentists | Low | 88.33 |
| Shadmehr et al. 2014 | Asia | 446 | Dentists | Low | 80.94 |
| Kursun et al. 2014 | Asia | 264 | DS | Low | 48.48 |
| Tirgar et al. 2015 | Asia | 60 | Dentists | Low | 93.33 |
| Gupta et al. (a) 2015 | Asia | 877 | Dentists | Low | 71.04 |
| Humann et al. 2015 | NA | 488 | DA | Low | 98.36 |
| Sakzewski et al. 2015 | Au | 466 | Dentists | Low | 86.05 |
| Kanaparthy et al. 2015 | Asia | 134 | DS | Moderate | 53.73 |
| Aljanakh et al. 2015 | Asia | 68 | Dentists | Low | 77.94 |
| Alghadir et al. 2015 | Asia | 146 | Dentists | Low | 84.93 |
| Hodacova et al. 2015 | Eu | 575 | Dentists | Low | 97.91 |
| Bhagwat et al. 2015 | Asia | 200 | Dentists | Low | 57.50 |
| Gupta et al. (b) 2015 | Asia | 2879 | Dentists | Low | 100.00 |
| Sahu et al. 2015 | Asia | 206 | Dentists | Low | 81.07 |
| Tamo et al. 2015 | Asia | 156 | Dentists | Low | 70.51 |
| Batham and Yasobant 2016 | Asia | 93 | Dentists | Low | 92.47 |
| Rehman et al. 2016 | Asia | 120 | DS | Low | 70.00 |
| Kriangkrai et al. 2016 | Asia | 68 | DS | Low | 100.00 |
| Rayyan et al. 2016 | Asia | 191 | DS | Low | 83.77 |
| Cho et al. 2016 | Asia | 401 | Dentists | Low | 86.78 |
| Phedy et al. 2016 | Asia | 241 | Dentists | Low | 63.49 |
| Freire et al. 2016 | SA | 94 | Dentists | Low | 90.43 |
| Al-Rawi et al. 2016 | Asia | 101 | Dentists | Low | 67.33 |
| Barry et al. 2017 | NA | 337 | DA | Low | 80.42 |
| Garbin et al. 2017 | SA | 204 | Dentists | Low | 81.37 |
| Taib et al. 2017 | Asia | 82 | Dentists | Low | 100.00 |
| Al-Hourani et al. 2017 | Asia | 81 | DA | Low | 100.00 |
| Revankar et al. 2017 | Asia | 150 | Dentists | Moderate | 81.33 |
| Hegde et al. 2018 | Asia | 200 | Dentists | Low | 97.00 |
| Hosseini et al. 2019 | Asia | 136 | Dentists | Low | 91.91 |
| Scepanovic et al. 2019 | Eu | 87 | ALL | Low | 79.31 |
| El Naji et al. 2019 | Asia | 134 | Dentists | Low | 19.40 |
| Benlidayi et al. 2019 | Asia | 99 | DS | Low | 85.86 |
| Zafar et al. 2019 | Asia | 142 | DS | Low | 58.45 |
| dos Santos et al. 2019 | SA | 241 | DS | Low | 82.57 |
| Meisha et al. 2019 | Asia | 234 | Dentists | Low | 70.09 |
| Gandham et al. 2019 | Asia | 150 | Dentists | Low | 58.67 |
| Khandan et al. 2020 | Asia | 51 | Dentists | Low | 84.31 |
| Netanely et al. 2020 | Asia | 102 | DA | Low | 89.22 |
| Harris et al. 2020 | NA | 647 | DA | Low | 82.53 |
| Pope-Ford et al. 2020 | NA | 14 | Dentists | Moderate | 92.86 |
| Senosy et al. 2020 | Asia | 66 | Dentists | Low | 89.39 |
| Shekhawat et al. 2020 | Asia | 72 | Dentists | Low | 100.00 |
| Rahman et al. 2020 | Asia | 82 | DA | Low | 81.71 |
| Uppada et al. (b) 2020 | Asia | 624 | Dentists | Low | 69.07 |
| Aboalshamat 2020 | Asia | 332 | ALL | Low | 81.33 |
| Ohlendorf et al. (b) 2020 | Eu | 450 | ALL | Low | 95.78 |
| Ohlendorf et al. (a) 2020 | Eu | 406 | DA | Low | 98.52 |
| Uppada et al. (a) 2020 | Asia | 156 | Dentists | Low | 84.62 |
| Kumar M et al. 2020 | Asia | 151 | ALL | Low | 58.28 |
| Berdouses et al. 2020 | Eu | 1500 | Dentists | Low | 54.07 |
| Ahmad et al. 2020 | Asia | 244 | Dentists | Low | 86.48 |
| Hashim et al. 2021 | Asia | 202 | DS | Moderate | 68.32 |
| Alnaser et al. 2021 | Asia | 186 | Dentists | Low | 47.85 |
| Gandolfi et al. 2021 | Eu | 284 | ALL | Low | 84.86 |
| Felemban et al. 2021 | Asia | 377 | DS | Low | 91.25 |
| Bhuvaneshwari et al. 2021 | Asia | 545 | Dentists | Low | 88.07 |
Eu: Europe; NA: North America; SA: South America; Au: Australia; DA: Dental auxillaries; DS: Dental students; ALL: All types of dental health care personnel; ROB: Risk of Bias.