This work is licensed under a Table 3.
GRADE summary of findings.
| Outcomes | No of participants (studies), follow up | Certainty of the evidence (GRADE) | Relative effect* (95% CI) | Anticipated absolute effects | |
|---|---|---|---|---|---|
| Risk with benign nodule | Risk difference contralateral cancer | ||||
| Age | 764 (4 observational studies) | ⨁⨁◯◯ Low |
OR 1.16 (0.82–1.64) | 228 per 1000 | 27 more per 1000 (33 fewer to 98 more) |
| Sex | 967 (6 observational studies) | ⨁⨁◯◯ Low |
OR 0.84 (0.56–1.26) | 262 per 1000 | 32 fewer per 1000 (96 fewer to 47 more) |
| Size of primary lesion | 601 (5 observational studies) | ⨁⨁◯◯ Low |
OR 1.18 (0.67–2.09) | 195 per 1000 | 27 more per 1000 (55 fewer to 141 more) |
| CLNM | 890 (4 observational studies) | ⨁⨁◯◯ Low |
OR 1.16 (0.83–1.62) | 237 per 1000 | 28 more per 1000 (32 fewer to 98 more) |
| HT | 931 (4 observational studies) | ⨁⨁◯◯ Low |
OR 1.57 (1.13–2.20) | 220 per 1000 | 87 more per 1000 (22 more to 163 more) |
| Multifocality of primary lesion | 764 (4 observational studies) | ⨁◯◯◯ Very lowa |
OR 3.93 (2.70–5.73) | 189 per 1000 | 289 more per 1000 (197 more to 383 more) |
| Multifocality of contralateral lesion | 690 (3 observational studies) | ⨁◯◯◯ Very lowb,c |
OR 1.32 (0.56–3.10) | 204 per 1000 | 49 more per 1000 (79 fewer to 239 more) |
| Capsular invasion | 764 (4 observational studies) | ⨁⨁◯◯ Low |
OR 1.61 (1.10–2.36) | 223 per 1000 | 93 more per 1000 (17 more to 181 more) |
*The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI); aThe Harbord test result for multifocality of primary lesion suggests that the presence of publication bias may distort the meta-analysis; bHigh I2 (68%) and non-overlapping CI suggest that important inconsistency which lowers our certainty in effect; cWide CIs do not exclude important benefit or harm which lowers our certainty in effect.
GRADE Working Group grades of evidence – High certainty: we are very confident that the true effect lies close to that of the estimate of the effect; Moderate certainty: we are moderately confident in the effect estimate, the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different; Low certainty: our confidence in the effect estimate is limited, the true effect may be substantially different from the estimate of the effect; Very low certainty: we have very little confidence in the effect estimate, the true effect is likely to be substantially different from the estimate of effect.