Table 1. Core characteristics of the studies included in Systematic review and Meta-analysis .
| Author | Year | Study design | Study location | Quality assessment | Sample size | Focusing group | Questionnaire administration | Outcome | Quality a | References |
| Ghosh et al | 2020 | Cross-sectional, questionnaire-based survey | Kolkata | <75% | 250 | Nurses | Face-to-face | Positive knowledge | 6 | 8 |
| Joshi et al | 2020 | Cross-sectional, questionnaire-based survey | Jodhpur | <75% | 1200 | Slums | Face-to-face | Positive knowledge | 6 | 9 |
| Vittal and Murthy | 2020 | Cross-sectional, questionnaire-based survey | Andhra Pradesh | <75% | 234 | Medical and nursing students | Self-administered | Poor knowledge and positive attitude | 3 | 10 |
| Kumar | 2020 | Cross-sectional, questionnaire-based survey | Uttar Pradesh | <75% | 195 | Female sex workers | Face-to-face | Positive knowledge | 5 | 11 |
| Sinha et al | 2020 | Cross-sectional, questionnaire-based survey | Alipurduar | <75% | 90 | Female sex workers | Face-to-face | Positive knowledge, negative attitude and positive practice | 6 | 12 |
| De Souza et al | 2019 | Cross-sectional, questionnaire-based survey | Mangalore | <75% | 1535 | Students, teachers and parents | Self-administered | Modest knowledge | 6 | 13 |
| Saheer et al | 2019 | Cross-sectional, questionnaire-based survey | Kerala | <75% | 341 | Dental students | Face-to-face | Positive knowledge, negative attitude | 5 | 14 |
| Biswas and Bandyopadhyay | 2019 | Cross-sectional, questionnaire-based survey | West Bengal | >75% | 296 | School students | Self-administered | Positive knowledge | 4 | 15 |
| Sarkar et al | 2019 | Cross-sectional, questionnaire-based survey | Kolkata | <75% | 220 | PLWHIV | Face-to-face | Negative perception | 5 | 16 |
| Limaye et al | 2019 | Cross-sectional, questionnaire-based survey | Mumbai | >75% | 199 | College students | Face-to-face | Positive knowledge and attitude | 5 | 17 |
| Meharda et al | 2019 | Cross-sectional, questionnaire-based survey | Ajmer | <75% | 288 | Slums | Face-to-face | Positive knowledge and poor practice | 5 | 18 |
| Singh et al | 2019 | Cross-sectional, questionnaire-based survey | Patna | <75% | 120 | General population | Self-administered | Positive knowledge and attitude, poor practice | 5 | 19 |
| Khandekar and Walvekar | 2018 | Cross-sectional, questionnaire-based survey | Kangrali | <75% | 400 | Married men | Face-to-face | Positive knowledge and attitude | 6 | 20 |
| Chowdary et al | 2018 | Cross-sectional, questionnaire-based survey | Guntur | <75% | 400 | Engineering students | Self-administered | Positive knowledge and attitude | 6 | 21 |
| Doda et al | 2018 | Cross-sectional, questionnaire-based survey | Uttarakhand | >75% | 385 | Consultants, residents, medical students, laboratory technicians, and nurses | Face-to-face | Positive knowledge, receptive attitude and satisfactory practice | 7 | 22 |
| Roy et al | 2018 | Cross-sectional, questionnaire-based survey | Eastern India | <75% | 36 | Medical students | Face-to-face | Positive knowledge | 5 | 23 |
| Dhanya et al | 2017 | Cross-sectional, questionnaire-based survey | Trichur district of Kerala | <75% | 206 | Dentists | Self-administered | Positive knowledge, attitude and practice | 6 | 24 |
| Banagi Yathiraj et al | 2017 | Cross-sectional, questionnaire-based survey | Manglore, Karnataka | <75% | 409 | PLWHIV | Face-to-face | Poor knowledge | 7 | 25 |
| Subbarao and Akhilesh | 2017 | Cross-sectional, questionnaire-based survey | Bengaluru and others | <75% | 350 | Engineering students | Face-to-face | Positive knowledge and negative attitude | 5 | 26 |
| Rahman and Santhosh Kumar | 2017 | Cross-sectional, questionnaire-based survey | Chennai | <75% | 100 | Undergraduate students | Self-administered | Positive knowledge and negative attitude | 6 | 27 |
| Ngaihte et al | 2017 | Cross-sectional, questionnaire-based survey | Delhi, Gandhinagar, Bhubaneswar, and Hyderabad | <75% | 503 | Dentists | Face-to-face | Positive knowledge and modest attitude | 6 | 28 |
| Kalyanshetti and Nikam | 2016 | Cross-sectional, questionnaire-based survey | Belgavi | <75% | 102 | Nursing students | Face-to-face | Positive knowledge | 5 | 29 |
| Baruah et al | 2016 | Cross-sectional, questionnaire-based survey | Jorhat | <75% | 261 | Adolescents | Face-to-face | Unclear | 3 | 30 |
| Chaudhary et al | 2016 | Cross-sectional, questionnaire-based survey | Jaipur | >75% | 613 | School students | Face-to-face | Positive knowledge | 6 | 31 |
| Gupta et al | 2016 | Cross-sectional, questionnaire-based survey | Himachal Pradesh | <75% | 150 | PLWHIV | Face-to-face | Positive knowledge, positive attitude and negative perception | 5 | 32 |
| Bhagavathula et al | 2015 | Cross-sectional, questionnaire-based survey | Warangal, Telangana | >75% | 542 | Family of PLWHIV | Face-to-face | Positive knowledge, modest attitude and positive perception | 8 | 33 |
| Kumar et al | 2015 | Cross-sectional, questionnaire-based survey | Raichur | <75% | 425 | Medical and dental students | Self-administered | Positive knowledge and attitude | 6 | 34 |
| Gupta et al | 2015 | Cross-sectional, questionnaire-based survey | Gorakhpur, Uttar Pradesh | <75% | 250 | Technical institute students | Face-to-face | Positive knowledge | 6 | 35 |
| Mittal et al | 2015 | Cross-sectional, questionnaire-based survey | Karnataka, Davangere | <75% | 100 | PLWHIV | Face-to-face | Poor knowledge and attitude | 6 | 36 |
| Dubey et al | 2014 | Cross-sectional, questionnaire-based survey | North India | <75% | 630 | College students | Face-to-face | Positive knowledge and attitude | 7 | 37 |
| Grover et al | 2014 | Cross-sectional, questionnaire-based survey | NCR | <75% | 600 | Dental students | Face-to-face | Positive knowledge and attitude | 5 | 38 |
| Jogdand and Yerpude | 2014 | Cross-sectional, questionnaire-based survey | Guntur | <75% | 138 | Medical students | Face-to-face | Positive knowledge | 6 | 39 |
| Oberoi et al | 2014 | Cross-sectional, questionnaire-based survey | NCR | <75% | 610 | Dental students | Face-to-face | Poor knowledge and positive attitude | 5 | 40 |
| Prabhu et al | 2014 | Cross-sectional, questionnaire-based survey | Tamilnadu | <75% | 102 | Dentists | Self-administered | Positive knowledge | 5 | 41 |
| Sakalle et al | 2014 | Cross-sectional, questionnaire-based survey | Indore district | <75% | 200 | School students | Face-to-face | Positive knowledge | 6 | 42 |
| Tondare et al | 2013 | Cross-sectional, questionnaire-based survey | Mumbai | <75% | 256 | Adolescents | Face-to-face | Positive knowledge and modest attitude | 6 | 43 |
| Jindal | 2013 | Cross-sectional, questionnaire-based survey | Moodbidri | <75% | 300 | College students | Face-to-face | Positive knowledge | 4 | 44 |
| Hemalatha et al | 2013 | Cross-sectional, questionnaire-based survey | Andhra Pradesh | <75% | 5580 | Female sex workers | Face-to-face | Positive knowledge | 4 | 45 |
| Gupta et al | 2013 | Cross-sectional, questionnaire-based survey | Lucknow | <75% | 215 | School students | Face-to-face | Positive knowledge | 5 | 46 |
| Aggarwal and Panat | 2013 | Cross-sectional, questionnaire-based survey | Bareilly | >75% | 460 | Dental students | Self-administered | Positive knowledge and attitude | 6 | 47 |
| Cooperman et al | 2013 | Cross-sectional, questionnaire-based survey | Mumbai | <75% | 300 | Women | Face-to-face | Positive knowledge | 6 | 48 |
| Fotedar et al | 2013 | Cross-sectional, questionnaire-based survey | Shimla | >75% | 191 | Dental students | Self-administered | Positive knowledge and negative attitude | 6 | 49 |
| Achappa et al | 2012 | Cross-sectional, questionnaire-based survey | Manglore | >75% | 200 | Nurses | Face-to-face | Positive knowledge, attitude and perception | 6 | 50 |
| Yadav et al | 2011 | Cross-sectional, questionnaire-based survey | Saurashtra | >75% | 1237 | Young population | Face-to-face | Positive knowledge | 5 | 51 |
| Hazarika | 2010 | Cross-sectional, questionnaire-based survey | Rural and urban | <75% | 132678 | General population | Face-to-face | Positive knowledge and attitude | 4 | 52 |
| Jayanna et al | 2010 | Cross-sectional, questionnaire-based survey | Karnataka | <75% | 393 | Female sex workers | Face-to-face | Unclear | 4 | 53 |
| Taraphdar et al | 2010 | Cross-sectional, questionnaire-based survey | Kolkata | >75% | 90 | PLWHIV | Face-to-face | Positive knowledge and attitude | 5 | 54 |
aJoanna Briggs Institute’s criteria