Gap finder
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.
2,112 questions in 171 reviews · Eyes and Vision
current versionsNo 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 |
|---|---|---|---|
Wavefront‐optimized procedures vs wavefront‐guided procedures Proportion of eyes that had lost 1 or more lines of best spectacle‐corrected visual acuity (BSCVA) post‐treatment:12 months ‐ overall estimate · Adults with refractive errors Wavefront excimer laser refractive surgery for adults with refractive errors (2020) · Cochrane | RR 0.99 [0.96, 1.02] | 5 studies · 622 participants | Low |
Cataract surgery with Hydrus microstent vs cataract surgery alone Proportion of participants who were medication‐free (not using eye drops) medium‐term · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | RR 1.63 [1.4, 1.88] | 2 studies · 619 participants | Moderate |
Hydrus microstent vs iStent trabecular micro‐bypass stent Mean change in number of IOP‐lowering drops instilled per day short‐term · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 1 study · 148 participants | Low |
Hydrus microstent vs iStent trabecular micro‐bypass stent Proportion of participants who required further glaucoma surgery, including laser · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 1 study · 148 participants | Very low |
Hydrus microstent vs iStent trabecular micro‐bypass stent Visual field progression · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | NR | No studies |
Hydrus microstent vs iStent trabecular micro‐bypass stent Mean change in health‐related quality of life · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | NR | No studies |
Hydrus microstent vs iStent trabecular micro‐bypass stent Proportion of participants experiencing intraoperative or postoperative complications short‐term · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 1 study · 148 participants | Low |
Cataract surgery with Hydrus microstent vs cataract surgery alone Mean change in unmedicated IOP (after washout) measured using Goldmann applanation tonometry medium‐term · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 2 studies · 619 participants | Moderate |
Cataract surgery with Hydrus microstent vs cataract surgery alone Mean change in the number of IOP‐lowering drops instilled per day medium‐term · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 2 studies · 619 participants | Low |
Cataract surgery with Hydrus microstent vs cataract surgery alone Proportion of participants who required further glaucoma surgery, including laser · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | RR 0.17 [0.03, 0.86] | 2 studies · 619 participants | Low |
Cataract surgery with Hydrus microstent vs cataract surgery alone Visual field progression · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | NR | No studies |
Cataract surgery with Hydrus microstent vs cataract surgery alone Mean change in health‐related quality of life · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | NR | No studies |
Cataract surgery with Hydrus microstent vs cataract surgery alone Proportion of participants experiencing intraoperative or postoperative complications medium‐term · people with cataracts and open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled… Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | NR | Low |
Hydrus microstent vs iStent trabecular micro‐bypass stent Proportion of participants who were medication‐free (not using eye drops) short‐term · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | RR 1.94 [1.21, 3.11] | 1 study · 148 participants | Low |
Hydrus microstent vs iStent trabecular micro‐bypass stent Mean change in unmedicated IOP (after washout) measured using Goldmann applanation tonometry short‐term · people with open angle glaucoma, many of whom had mild or moderate glaucoma, which was well‐controlled with medication Ab interno trabecular bypass surgery with Schlemm´s canal microstent (Hydrus) for open angle glaucoma (2020) · Cochrane | no estimate extracted | 1 study · 148 participants | Moderate |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Mean UCVA, 12 months after surgery (unit LogMAR) · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | no estimate extracted | 1 study · 42 participants | Low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Proportion of eyes within ± 0.5 diopters of target refraction, 12 months after surgery (unit diopters) · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | RR 0.97 [0.85, 1.11] | 1 study · 79 participants | Low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Mean spherical equivalent of the refractive error, 12 months after surgery (unit diopters) · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | no estimate extracted | 3 studies · 168 participants | Low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Corneal haze, any time point · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | RR 0.33 [0.01, 7.96] | 1 study · 86 participants | Very low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Dry eye, any time point · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | RR 5.74 [2.92, 11.29] | 1 study · 183 participants | Low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Diffuse lamellar keratitis, any time point · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | RR 0.27 [0.1, 0.78] | 3 studies · 134 participants | Low |
Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome vs LASIK with a femtosecond laser Epithelial ingrowth, any time point · adults (18 years) with more than 0.5 diopters of myopia or myopic astigmatism Laser‐assisted in‐situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a… (2020) · Cochrane | RR 1.04 [0.11, 9.42] | 2 studies · 102 participants | Very low |
Intervention NR Test (measure and/or threshold) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 95 participants | Ungraded |
Intervention NR LACD (cut‐off: ≤25%) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 108 participants | Moderate |
Intervention NR Oblique flashlight test (grade 1) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 72 participants | Low |
Intervention NR SPAC (≤5 and/or S or P) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 207 participants | Moderate |
Intervention NR Scheimpflug photography (ACD central) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 126 participants | Moderate |
Intervention NR AS‐OCT (subjective assessment) Non‐contact tests for identifying people at risk of primary angle closure glaucoma (2020) · Cochrane | no estimate extracted | 270 participants | Moderate |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with re‐epithelialization and complete healing with or without scar formation at 4 to 8 weeks Assessed by slit‐lamp biomicroscopy · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 15 participants | Very low |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with BCVA of 20/100 or better at 4 to 8 weeks Assessed using a logMAR chart · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 12 participants | Very low |
PACK‐CXL with standard therapy vs standard therapy alone Mean change from baseline in BCVA at 4 to 8 weeks Assessed using a logMAR chart · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 0 participants | Ungraded |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with a reduction in corneal infiltrate at 4 to 8 weeks Assessed by outcome assessors · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 0 participants | Ungraded |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with reduction in intraocular inflammation at 4 to 8 weeks Assessed by corneal keratic precipitates, anterior chamber cellular reaction, or other appropriate measure · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 0 participants | Ungraded |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with treatment failure at 4 to 8 weeks Assessed by outcome assessors · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 1 study · 32 participants | Low |
PACK‐CXL with standard therapy vs standard therapy alone Proportion of participants with adverse events at 4 to 8 weeks Assessed by outcome assessors · participants of any age with confirmed cases of bacterial keratitis Corneal collagen cross‐linking for bacterial infectious keratitis (2020) · Cochrane | no estimate extracted | 1 study · 32 participants | Low |
Emixustat vs placebo Change in BCVA from baseline to 24 months* · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 1 study · 320 participants | Low |
Fenretinide vs placebo Proportion of participants losing ≥ 10 EDTRS letters · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Fenretinide vs placebo Progression of geographic atrophy · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 1 study · 142 participants | Low |
Fenretinide vs placebo Progression to advanced AMD (geographic atrophy or neovascular) · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Fenretinide vs placebo Mean change in macular sensitivity · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Fenretinide vs placebo Adverse events · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 1 study · 246 participants | Low |
Emixustat vs placebo Proportion of participants losing ≥ 15 EDTRS letters at 24 months** · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | RR 0.91 [0.59, 1.4] | 1 study · 498 participants | Low |
Emixustat vs placebo Proportion of participants losing ≥ 10 EDTRS letters** · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Emixustat vs placebo Progression of geographic atrophy · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 1 study · 503 participants | Low |
Emixustat vs placebo Progression to advanced AMD (geographic atrophy or neovascular) · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Emixustat vs placebo Mean change in macular sensitivity · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
Emixustat vs placebo Adverse events · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 2 studies · 575 participants | Moderate |
Fenretinide vs placebo Change in BCVA from baseline to 24 months · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | 1 study · 246 participants | Low |
Fenretinide vs placebo Proportion of participants losing ≥ 15 EDTRS letters · people with geographic atrophy due to AMD Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy… (2020) · Cochrane | no estimate extracted | NR | No studies |
No tea tree oil group vs tea tree oil (intervention) group Mean change in number of Demodex mites per 8 eyelashes at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 3 studies · 215 participants | Very low |