Author (year) | 1.1 | 1.2 | 1.3 | 1.4 | 1.5 | 1.6 | 1.7 | 1.8 | 1.10 | 1.11 | 1.12 | 1.13 | 1.14 | 2.1 |
|---|
Firns (2015) [46] | Yes | Can’t say | Can’t say | Can’t say | Can’t say | Can’t say | Yes | Yes | Yes | Yes | Can’t say | Yes | No | Cannot determine |
Gaskins (2019) [48] | Yes | Can’t say | Yes | Does not apply | Noneb | No | Yes | Yes | Yes | Yes | No | Yes | Yes | Acceptable |
Karayiannis (2018) [49] | Yes | Can’t say | No | No | None | No | Yes | Yes | Yes | Yes | No | Yes | Yes | Acceptable |
Ricci (2019) [50] | Yes | Can’t say | No | No | None | No | No | Yes | Yes | Yes | No | Yes | Yes | Acceptable |
Sugawa (2018) [51] | Yes | Can’t say | Yes | No | None | No | Yes | Yes | Yes | Yes | No | Yes | Yes | Acceptable |
Sun (2019) [52] | Yes | Can’t say | No | No | Can’t say | No | No | Yes | No | Yes | No | Yes | Yesa | Acceptable* |
Twigt (2012) [53] | Yes | Can’t say | No | No | None | No | Yes | Yes | No | Yes | No | Yes | Yes | Acceptable |
Vujkovic (2010) [54] | Yes | Can’t say | No | Does not apply | None | No | Yes | Yes | Yes | Yes | No | Yes | Yes | Acceptable |
Jahangirifar (2019) [47] | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Not fully assessed c |
- *Rated as acceptable for the primary outcome of embryo yield, low quality for biochemical and clinical pregnancy
- a p-value
- b All ‘in study cycles’ included, all participants had at least one ART ‘cycle’, number of women who dropped out not stated
- c study contained a measure of association for clinical pregnancy that fell outside the confidence interval (OR 0.14, 95% CI: 0.3–0.7)
- 1.1 Study addresses an appropriate and clearly focused question
- 1.2 Groups being studied are selected from source populations comparable in all respects other than the factor under investigation
- 1.3 Study indicates the number of people asked to take part who did so
- 1.4 Likelihood that some eligible subjects might have outcome at enrolment is assessed and considered in the analysis
- 1.5 Study states the percentage of individuals recruited into each arm of the study who dropped out before the study was completed
- 1.6 Comparison is made between full participants and those lost to follow up, by exposure status
- 1.7 Outcomes are clearly defined
- 1.8 Assessment of the outcome is made blind to exposure status
- 1.9 Where blinding was not possible there is recognition that knowledge of exposure status could have influenced assessment of outcome (not applicable in any study)
- 1.10 Method of exposure assessment is reliable
- 1.11 Evidence from other sources is used to demonstrate that the method of outcome assessment is valid and reliable
- 1.12 Exposure level or prognostic factor is assessed more than once
- 1.13 Main potential confounders are identified and considered in the design and analysis
- 1.14 Confidence intervals are provided
- 2. 1 Overall quality based on how well the study has done to minimise the risk of bias or confounding (high, acceptable, low)
