Table 2.
Characteristics of included studies
| Study and year published | Clearly stated aim | Clearly defined study population | Study sample representative of the source population | Attempt made to adjust for confounding | Attempt made to validate survey responses to institutional records where possible | Discussion of study limitations | Quality grading |
|---|---|---|---|---|---|---|---|
| Gagneux-Brunon 2021 | Yes | Yes | Unable to determine | Unable to determine | No | Yes | 3 |
| Kwok 2021 | Yes | Yes | Yes | Unable to determine | No | Yes | 4 |
| Papagiannis 2020 | Yes | Yes | Unable to determine | Unable to determine | No | Yes | 3 |
| Shaw 2021 | Yes | Yes | Yes | Unable to determine | No | Yes | 4 |
| Shekhar 2021 | Yes | Yes | Unable to determine | Unable to determine | No | Yes | 3 |
| Unroe 2021 | Yes | Yes | Yes | Yes | No | Yes | 5 |
| Verger 2021 | Yes | Yes | Yes | Unable to determine | No | Yes | 4 |
| Wang 2020 | Yes | Yes | Yes | Unable to determine | No | Yes | 4 |
| Zhang 2021 | YesUS, | Yes | Unable to determine | Unable to determine | No | Yes | 3 |