Cochrane · systematic review · CD012191

Risk‐reducing medications for primary breast cancer: a network meta‐analysis

Mocellin, S, Goodwin, A, Pasquali, S · Cochrane Database of Systematic Reviews · 2019 · Cochrane Library

Breast CancerAMSTAR 2: not assessed

SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.

Questions

current version

GRADE rated

No studies

Included studies

No studies 0 · 0%Ungraded 0 · 0%Very low 0 · 0%Low 1 · 20%Moderate 2 · 40%High 2 · 40%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Questions and results

Tamoxifen versus placebo

Population: women with above‐average risk of developing breast cancer

2 questions

Outcome	Effect	Evidence	Status / GRADE
Overall breast cancer incidence Tamoxifen vs placebo	RR 0.68 [0.62, 0.76]	3 studies · 22832 participants	Moderate Downgraded: inconsistency
Severe toxicity Tamoxifen vs placebo	RR 1.28 [1.12, 1.47]	2 studies · 20361 participants	Moderate Downgraded: inconsistency

Aromatase inhibitors versus placebo

Population: women with above‐average risk of developing breast cancer

2 questions

Outcome	Effect	Evidence	Status / GRADE
Overall breast cancer incidence Aromatase inhibitors vs placebo	RR 0.47 [0.35, 0.63]	2 studies · 8424 participants	High
Severe toxicity Aromatase inhibitors vs placebo	RR 1.18 [1.09, 1.28]	2 studies · 8352 participants	High

Aromatase inhibitors versus tamoxifen (indirect comparison)a

Population: women with above‐average risk of developing breast cancer

1 question

Outcome	Effect	Evidence	Status / GRADE
Overall breast cancer incidence Aromatase inhibitors vs tamoxifen (indirect comparison)a	RR 0.67 [0.46, 0.98]	5 studies · 31256 participants	Low Downgraded: inconsistency