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Search review questions

Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.

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Intervention or exposure

Comparison

Outcome

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Review versions

2,112 questions in 171 reviews · Eyes and Vision

current versions

No studies 587 · 27.8%Ungraded 95 · 4.5%Very low 446 · 21.1%Low 557 · 26.4%Moderate 361 · 17.1%High 66 · 3.1%

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.

Question	Effect	Evidence	Status / GRADE
Intervention NR Uncorrected visual acuity (UCVA) (measured using logMAR scale. A score of 0 = good vision, higher score is worse vision) · people with keratoconus Corneal collagen cross‐linking for treating keratoconus (2015) · Cochrane	no estimate extracted	1 study · 94 participants	Very low
Intervention NR Corneal thickness at the thinnest part of the cornea (measured in microns) · people with keratoconus Corneal collagen cross‐linking for treating keratoconus (2015) · Cochrane	no estimate extracted	1 study · 94 participants	Very low
Intervention NR Absolute spherical equivalent (measured in dioptres) · people with keratoconus Corneal collagen cross‐linking for treating keratoconus (2015) · Cochrane	no estimate extracted	1 study · 94 participants	Very low
Intervention NR Quality of life · people with keratoconus Corneal collagen cross‐linking for treating keratoconus (2015) · Cochrane	no estimate extracted	NR	No studies
Intervention NR Adverse effects · people with keratoconus Corneal collagen cross‐linking for treating keratoconus (2015) · Cochrane	no estimate extracted	1 study · 3 participants	Ungraded
Regular‐dose postoperative 5‐Fluorouracil vs control Failure at 12 months · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.39 [0.26, 0.58]	6 studies · 469 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ hypotonous maculopathy ‐ high risk of failure ‐ not reported · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ shallow anterior chamber ‐ high risk of failure · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 2.41 [0.88, 6.58]	2 studies · 239 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ epithelial toxicity ‐ high risk of failure · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.25 [1.12, 1.38]	2 studies · 239 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Failure at 12 months ‐ combined surgery · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	2 studies · 118 participants	Very low
Regular‐dose postoperative 5‐Fluorouracil vs control Mean intraocular pressure at 12 months ‐ combined surgery · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	2 studies · 118 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ wound leak ‐ combined surgery · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.9 [0.36, 2.23]	2 studies · 118 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ hypotonous maculopathy ‐ combined surgery ‐ not reported · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ shallow anterior chamber ‐ combined surgery · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	2 studies · 118 participants	Very low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ epithelial toxicity ‐ combined surgery · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 3.04 [1.56, 5.92]	2 studies · 118 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Failure at 12 months ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.21 [0.06, 0.68]	2 studies · 112 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Mean intraocular pressure at 12 months · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Regular‐dose postoperative 5‐Fluorouracil vs control Mean intraocular pressure at 12 months ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	2 studies · 112 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ wound leak ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.47 [0.04, 4.91]	2 studies · 112 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ hypotonous maculopathy ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	1 study · 62 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ shallow anterior chamber ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.47 [0.04, 4.91]	2 studies · 112 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ epithelial toxicity ‐ primary trabeculectomy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 5.85 [2.04, 16.83]	2 studies · 112 participants	Low
Low‐dose postoperative 5‐Fluorouracil vs control Failure at 12 months · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.93 [0.7, 1.24]	1 study · 76 participants	Very low
Low‐dose postoperative 5‐Fluorouracil vs control Mean intraocular pressure at 12 months · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	1 study · 76 participants	Very low
Low‐dose postoperative 5‐Fluorouracil vs control Complications ‐ wound leak · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.33 [0.01, 7.93]	1 study · 76 participants	Very low
Low‐dose postoperative 5‐Fluorouracil vs control Complications ‐ hypotonous maculopathy ‐ not reported · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Low‐dose postoperative 5‐Fluorouracil vs control Complications ‐ shallow anterior chamber ‐ not reported · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ wound leak · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.38 [0.93, 2.04]	6 studies · 469 participants	Low
Low‐dose postoperative 5‐Fluorouracil vs control Complications ‐ epithelial toxicity ‐ not reported · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Intraoperative 5‐Fluorouracil vs placebo or control Failure at 12 months Need for repeat surgery or uncontrolled IOP (usually more than 22 mm Hg) despite additional topical or systemic medications · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.68 [0.51, 0.92]	4 studies · 711 participants	High
Intraoperative 5‐Fluorouracil vs placebo or control Mean intraocular pressure at 12 months · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	4 studies · 711 participants	High
Intraoperative 5‐Fluorouracil vs placebo or control Complications ‐ wound leak · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.36 [1, 1.84]	4 studies · 711 participants	High
Intraoperative 5‐Fluorouracil vs placebo or control Complications ‐ hypotonous maculopathy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.47 [0.42, 5.12]	4 studies · 711 participants	Moderate
Intraoperative 5‐Fluorouracil vs placebo or control Complications ‐ shallow anterior chamber · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.99 [1.22, 3.22]	4 studies · 711 participants	High
Intraoperative 5‐Fluorouracil vs placebo or control Complications ‐ epithelial toxicity · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.23 [0.85, 1.77]	4 studies · 711 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ hypotonous maculopathy · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	NR	No studies
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ shallow anterior chamber · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.84 [0.76, 4.46]	6 studies · 469 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ epithelial toxicity · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.56 [1.36, 1.78]	6 studies · 469 participants	Low
Regular‐dose postoperative 5‐Fluorouracil vs control Failure at 12 months ‐ high risk of failure · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 0.44 [0.29, 0.68]	2 studies · 239 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Mean intraocular pressure at 12 months ‐ high risk of failure · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	no estimate extracted	1 study · 26 participants	Moderate
Regular‐dose postoperative 5‐Fluorouracil vs control Complications ‐ wound leak ‐ high risk of failure · participants with glaucoma surgery 5‐Fluorouracil for glaucoma surgery (2014) · Cochrane	RR 1.64 [1.04, 2.58]	2 studies · 239 participants	Moderate
Intervention NR BCVA gain of 15 letters or more ( · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	RR 2.71 [2.1, 3.49]	6 studies · 937 participants	High
Intervention NR BCVA loss of 15 letters or more ( · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	RR 0.2 [0.12, 0.34]	5 studies · 766 participants	High
Intervention NR Mean change in BCVA from baseline ( · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	MD 15.23 [11.57, 18.89]	6 studies · 937 participants	Moderate
Intervention NR Mean change from baseline in central retinal thickness ( · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	no estimate extracted	3 studies · 481 participants	Moderate
Intervention NR Complication: iris or retinal neovascularisation ( · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	RR 0.18 [0.09, 0.36]	6 studies · 936 participants	High
Intervention NR Ocular adverse events: endophthalmitis at 6 months · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	no estimate extracted	6 studies · 937 participants	High
Intervention NR Mean change from baseline in quality of life score (NEI VFQ‐25 instrument) · participants with CRVO macular oedema of duration less than 9 months (mean < 3 months) and no prior treatment Anti‐vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion (2014) · Cochrane	no estimate extracted	3 studies · 743 participants	Moderate
Intervention NR Good functional vision: presenting visual acuity of 6/12 or better at 6‐8 weeks · people with age‐related cataract Manual small incision cataract surgery (MSICS) with posterior chamber intraocular lens versus extracapsular… (2014) · Cochrane	no estimate extracted	2 studies · 806 participants	Low
Intervention NR Poor visual outcome after surgery: best‐corrected visual acuity of < 6/60 at 6‐8 weeks. · people with age‐related cataract Manual small incision cataract surgery (MSICS) with posterior chamber intraocular lens versus extracapsular… (2014) · Cochrane	no estimate extracted	2 studies · 806 participants	Low