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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.

Limit to evidence status or GRADE (optional)

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.

QuestionEffectEvidenceStatus / GRADE
Intervention NR
0.5% CMC vs. sodium hyaluronate · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted2 studies · 131 participantsLow
Intervention NR
0.5% CMC vs. 0.3% HPMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted3 studies · 268 participantsUngraded
Intervention NR
0.5% CMC vs 1% CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 103 participantsUngraded
Intervention NR
lipid‐based CMC vs. aqueous‐based CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 315 participantsUngraded
Intervention NR
Two different concentrations of CMC + hyaluronic acid vs CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 305 participantsUngraded
Intervention NR
0.5% CMC vs 0.5% CMC + castor oil vs. 1.0% glycerine + castor oil · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 18 participantsUngraded
Intervention NR
1.0% CMC vs. 0.18% sodium hyaluronate · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 21 participantsUngraded
Intervention NR
1.0% CMC vs. 0.3% HPMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted2 studies · 77 participantsUngraded
Intervention NR
1.0% CMC vs. 0.4% carbomer · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 60 participantsUngraded
Intervention NR
a) · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted2 studies · 297 participantsLow
Intervention NR
0.2% carbomer vs. 0.3% HPMC vs. 0.3% anhydrous liquid lanolin · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 67 participantsUngraded
Intervention NR
0.2% carbomer vs. HP‐guar · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 30 participantsUngraded
Intervention NR
0.3% carbomer vs. 0.18% sodium hyaluronate · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted2 studies · 368 participantsUngraded
Intervention NR
Carbomer gels containing different preservatives · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 179 participantsUngraded
Intervention NR
0.2% PAA vs. 1.4% PVA · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted2 studies · 159 participantsUngraded
Intervention NR
1.4% PVA vs. 0.1% sodium hyaluronate · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 35 participantsUngraded
Intervention NR
1.4% PVA vs. carbomer · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 55 participantsUngraded
Intervention NR
0.3% HPMC vs. 0.4% hyaluronic acid · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 113 participantsUngraded
Intervention NR
Two different products containing 0.3% HPMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 37 participantsUngraded
Intervention NR
0.3% HPMC with vs without bicarbonate · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 27 participantsUngraded
Intervention NR
b) · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 19 participantsUngraded
Intervention NR
0.3% HPMC vs. 1.25% castor oil · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 53 participantsUngraded
Intervention NR
Trehalose + hyaluronic acid vs. PEG + PG + HP‐guar · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 17 participantsUngraded
Intervention NR
c) · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 49 participantsUngraded
Intervention NR
PEG 400 + PG + HP‐guar vs. CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted6 studies · 471 participantsUngraded
Intervention NR
PEG 400 + PG or sodium hyaluronate vs. HPMC or CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 30 participantsUngraded
Intervention NR
0.4% PEG 400 + PG vs. 0.25% PEG 400 · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 22 participantsUngraded
Intervention NR
0.25% PEG 400 vs.1% CMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 104 participantsUngraded
Intervention NR
0.25% PEG 400 vs. 0.3% HPMC · people with dry eye
Over the counter (OTC) artificial tear drops for dry eye syndrome (2016) · Cochrane
no estimate extracted1 study · 20 participantsUngraded
Intervention NR
Complete success ( · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
RR 0.71 [0.46, 1.08]1 study · 42 participantsLow
Intervention NR
Qualified success ( · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
RR 1 [0.87, 1.14]1 study · 42 participantsModerate
Intervention NR
Mean IOP ( · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
no estimate extracted2 studies · 66 participantsLow
Intervention NR
Adverse events ‐ wound leaks · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
OR 1.28 [0.32, 5.04]3 studies · 102 participantsVery low
Intervention NR
Adverse events ‐ hypotony · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
OR 0.78 [0.2, 3.11]4 studies · 126 participantsVery low
Intervention NR
Adverse events ‐ shallow anterior chamber · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
OR 3.2 [0.32, 32.52]2 studies · 66 participantsVery low
Intervention NR
Adverse events ‐ endophthalmitis · People undergoing trabeculectomy surgery with glaucoma
Anti‐vascular endothelial growth factor for control of wound healing in glaucoma surgery (2016) · Cochrane
no estimate extracted1 study · 42 participantsUngraded
Intervention NR
UCVA of 20/20 or better at 12 months post treatment · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
RR 0.98 [0.92, 1.05]NRLow
Intervention NR
Within ± 0.50 D of target refraction at 12 months post treatment · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
RR 0.93 [0.84, 1.03]NRLow
Intervention NR
Loss of 1 or more lines of BSCVA at 12 months post treatment · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
RR 3 [0.13, 71.96]NRVery low
Intervention NR
Mean spherical equivalent at 12 months post treatment · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
no estimate extractedNRModerate
Intervention NR
Adverse outcomes ‐ corneal haze score at 12 months (grade 1.0 ‐ more prominent haze that does not interfere with visibility of fine iris details; grade 2.0 ‐ mild obscuration of iris details; grade 3.0 ‐ moderate obscuration of iris and lens; and ... · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
no estimate extractedNRVery low
Intervention NR
Adverse outcomes ‐ glare and halo scores at 3 months (grade 0 ‐ none; grade 1 ‐ very low; grade 2 ‐ low; grade 3 ‐ moderate; grade 4 ‐ high; and grade 5 ‐ very high) · adult participants (≥ 18 years) with myopia
Laser‐assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of… (2016) · Cochrane
no estimate extractedNRVery low
Intervention NR
Proportion of successful procedures at 1 year and up to 5 years after surgery (no exposure/extrusion) · people with anophthalmic sockets
Integrated versus non‐integrated orbital implants for treating anophthalmic sockets (2016) · Cochrane
RR 0.92 [0.84, 1.01]1 study · 150 participantsLow
Intervention NR
Socket and prosthesis motility (horizontal) · people with anophthalmic sockets
Integrated versus non‐integrated orbital implants for treating anophthalmic sockets (2016) · Cochrane
no estimate extracted1 study · 100 participantsVery low
Intervention NR
Socket and prosthesis motility (vertical) · people with anophthalmic sockets
Integrated versus non‐integrated orbital implants for treating anophthalmic sockets (2016) · Cochrane
no estimate extracted1 study · 100 participantsVery low
Intervention NR
Any adverse outcomes (e.g. extrusions or migration, infections, ectropion) · people with anophthalmic sockets
Integrated versus non‐integrated orbital implants for treating anophthalmic sockets (2016) · Cochrane
RR 17.82 [0.98, 324.67]1 study · 150 participantsVery low
Intervention NR
Improvement in visual impairment at 6 months · people residing in communities endemic for onchocerciasis
Doxycycline plus ivermectin versus ivermectin alone for treatment of patients with onchocerciasis (2016) · Cochrane
RR 1.06 [0.8, 1.39]1 study · 240 participantsVery low
Intervention NR
Parasitological outcomes · people residing in communities endemic for onchocerciasis
Doxycycline plus ivermectin versus ivermectin alone for treatment of patients with onchocerciasis (2016) · Cochrane
no estimate extractedNRVery low
Intervention NR
Clinical outcomes: improvement in optic atrophy, chorioretinitis, or sclerosing keratitis at 6 months · people residing in communities endemic for onchocerciasis
Doxycycline plus ivermectin versus ivermectin alone for treatment of patients with onchocerciasis (2016) · Cochrane
no estimate extractedNRVery low
Intervention NR
Clinical outcomes: improvement in iridocyclitis at 6 months · people residing in communities endemic for onchocerciasis
Doxycycline plus ivermectin versus ivermectin alone for treatment of patients with onchocerciasis (2016) · Cochrane
RR 1.24 [0.69, 2.22]1 study · 240 participantsVery low