Table 1.
Characteristics of the included studies.
| Study | Country | Respondents | Parent’s Age (in years) | Gender of Children | Vaccination Status | Children’s Age (in years) | Recruitment Site | Data Collection Period | Sample Size | Number of Vaccinated Children | Number of Non-Vaccinated Children |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Baumann et al. (2019) [29] | Denmark | Mothers | <20–>40 (at parturition) | Female | Vaccinated vs. non-vaccinated | 13 | Danish Civil Registration System (CRS) | 2015–2016 | 3558 | 2899 | 659 |
| Bedford et al. (2021) [35] | United Kingdom | Parents | Not specified | Female | Initiated vs. non-initiated | 14 | Millennium Cohort Study (MCS) | 2014–2016 | 5654 | 5265 | 399 |
| Brabin et al. (2006) [16] | United Kingdom | Parents | ≤30–>45 | Not specified | Consenting vs. non-consenting | 11–12 | Manchester City Council’s Education Department | 2005 | 317 | 239 | 78 |
| Dahlström et al. (2009) [17] | Sweden | Mothers and fathers | <41–>45 | Female and male | Intention vs. non-intention | 12–15 | Swedish Population Register | 2007 | 13,946 | 10,537 | 3303 |
| David et al. (2022) [30] | France | Parents | 32–58 | Female | Vaccinated vs. non-vaccinated | 9–19 | Hospital Femme-Mère Enfant and Necker-Enfants-Malades | 2020–2021 | 71 | 28 | 43 |
| Dib et al. (2022) [37] | France | Mothers | 43.5 (mean) | Female | Vaccinated vs. non-vaccinated | 11–14 | Not specified | Not specified | 1102 | 425 | 677 |
| Domínguez-Riscart et al. (2023) [40] | Spain | Caregivers (mostly mothers) | 44.1 (mean) | Trans-gender | Intention vs. non-intention | 9–16 | Hospital Puerta del Mar and Universitario Reina Sofia | 2022 | 65 | 14 | 51 |
| Donders et al. (2007) [18] | Belgium | Mothers | 35.8 (mean) | Female and male | Intention vs. non-intention | Not specified | Hospital Hart | 2007 | 309 | 285 | 23 |
| Feiring et al. (2015) [31] | Norway | Mothers and fathers | ≤25–>35 (at parturition) | Female | Initiated vs. non-initiated | Not specified | The Norwegian Central Population Registry | 2013 | 84,139 | 65,843 | 18,296 |
| Ganczak et al. (2018) [26] | Poland | Mothers and fathers | 29–67 | Not specified | Intention vs. non-intention | 13–16 | High School | 2013–2014 | 450 | 383 | 67 |
| Gefenaite et al. (2012) [32] | Netherlands | Parents | 35–55 | Female | Vaccinated vs. non-vaccinated | 13 | Institute for Public Health and the Environment | 2009 | 469 | 307 | 162 |
| Grandahl et al. (2016) [22] | Sweden | Parents | 43.2 (mean) | Children | Consenting vs. declining | 11–12 | Swedish National Population Register | Not specified | 200 | 186 | 14 |
| Haesebaert et al. (2014) [19] | France | Mothers | 18–65 | Female | Favorable vs. uncertain/opposed | 14–18 | General Practitioner | 2008 | 91 | 55 | 36 |
| Hansen et al. (2015) [20] | Norway | Mothers and fathers | <35–≥50 | Female | Initiated vs. non-initiated | 12–13 | Norwegian Immunisation Registry (SYSVAK) | 2013 | 90,540 | 70,870 | 19,670 |
| Lenselink (2007) [23] | Netherlands | Mothers and fathers | 42.2 (mean) | Female and male | Intention vs. non-intention | 10–12 | School | Not specified | 356 | 313 | 32 |
| Mari et al. (2022) [24] | Italy | Parents | 44.5 (mean) | Male | Intention vs. non-intention | 6–18 | Buzzi Hospital | 2021–2022 | 339 | 251 | 88 |
| Marlow et al. (2007) [38] | United Kingdom | Mothers | 41.1 (mean) | Female | Consenting vs. non-consenting | 8–14 | School | 2006 | 684 | 513 | 171 |
| Pelucchi et al. (2010) [21] | Italy | Mothers and fathers | <40–≥50 | Female and male | Consenting vs. non-consenting | 10- 13 | School | 2008 | 2144 | 1438 | 706 |
| Rousset-Jablonski (2021) [33] | France | Accompanying adults (parents) | 32–58 | Female | Vaccinated vs. non-vaccinated | 9–17 | Pediatric or pediatric and adult Cystic Fibrosis centers | 2018–2019 | 104 | 34 | 76 |
| Schreiber et al. (2015) [34] | Denmark | Mothers | Not specified | Female | Initiated vs. non-initiated | Not specified | Danish Civil Registration System | Not specified | 65,926 | 61,162 | 4764 |
| Sobierajski et al. (2023) [27] | Poland | Parents | <30–>49 | Children | Vaccinated/intention vs. non-vaccinated/non-intention | 9–15 | Central Statistical Office’s data | 2022 | 360 | 233 | 127 |
| Spencer et al. (2013) [36] | United Kingdom | Mothers | 25–65 | Female | Initiation vs. non-initiation | 12–15 | National Health Authority Information System | Not specified | 112,451 | 89,088 | 23,363 |
| Sypien & Zielonka (2022) [28] | Poland | Parents | ≤34–>34 | Female and male | Intention vs. non-intention | Not specified | University Children’s Hospital | 2021 | 302 | 95 | 207 |
| Waller et al. (2019) [25] | United Kingdom | Parents | 40.5 (mean) | Female and male | Decided vs. non-decided/undecided | 9–12 | School | 2019 | 1156 | 718 | 438 |
| Woodhall et al. (2007) [39] | Finland | Parents | ≤40–≥51 | Female and male | Accepting vs. declining | 15 (mean) | Tampere city | 2005 | 727 | 622 | 105 |