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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 |
|---|---|---|---|
No tea tree oil group vs tea tree oil (intervention) group Mean change in participant‐reported change in symptoms at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 2 studies · 246 participants | Low |
No tea tree oil group vs tea tree oil (intervention) group Participants with an improvement in visual acuity at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 1 study · 86 participants | Low |
No tea tree oil group vs tea tree oil (intervention) group Mean change in (or mean) number of cylindrical dandruff at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
No tea tree oil group vs tea tree oil (intervention) group Proportion of participants with meibomian gland dysfunction at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
No tea tree oil group vs tea tree oil (intervention) group Proportion of participants experiencing conjunctival injection (redness) at 4–6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
No tea tree oil group vs tea tree oil (intervention) group Adverse events at 4‐6 weeks · Demodex blepharitis Tea tree oil for Demodex blepharitis (2020) · Cochrane | no estimate extracted | 3 studies · 318 participants | Very low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Dry eye symptoms, measured using the SPEED score at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | MD 0 | NR | Very low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Incidence of adverse events at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | no estimate extracted | NR | Very low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Sodium fluorescein TBUT, measured in seconds, at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | MD 2.02 | NR | Low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) NIBUT, measured in seconds, at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | MD 5.5 | NR | Very low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Tear osmolarity, measured in mOsmol/L, at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | no estimate extracted | NR | Low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Meibomian gland orifice plugging, at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | no estimate extracted | NR | Very low |
IPL (with/without MGX) vs sham or no treatment (with/without MGX) Corneal sodium fluorescein staining, measured using a validated clinical scale, at 3 months of · people with meibomian gland dysfunction Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction (2020) · Cochrane | no estimate extracted | NR | Very low |
Antibiotic vs control Active trachoma Clinical assessment: active trachoma defined as TF, TI, or both  · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | RR 0.78 [0.69, 0.89] | 9 studies · 1961 participants | Low |
Oral azithromycin vs control Ocular C trachomatis infection · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral azithromycin vs control Antibiotic resistance Proportion of samples showing evidence of resistance to antibiotic · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 4 studies · 1354 participants | Ungraded |
Oral azithromycin vs control Adverse effects · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 2 studies · 3069 participants | Ungraded |
Oral azithromycin vs topical tetracycline Active trachoma Clinical assessment: active trachoma defined as TF, TI, or both · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 3 studies · 6002 participants | Low |
Oral azithromycin vs topical tetracycline Ocular C trachomatis infection Positive test for C trachomatis infection identified by culture, staining on conjunctival smears, or nucleic acid amplification methods · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 3 studies · 5773 participants | Low |
Oral azithromycin vs topical tetracycline Antibiotic resistance Proportion of samples showing evidence of resistance to antibiotic · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral azithromycin vs topical tetracycline Adverse effects · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 3 studies · 6002 participants | Ungraded |
Antibiotic vs control Ocular C trachomatis infection Positive test for C trachomatis infection identified by culture, staining on conjunctival smears, or nucleic acid amplification methods · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | RR 0.81 [0.63, 1.04] | 4 studies · 297 participants | Low |
Antibiotic vs control Antibiotic resistance Proportion of samples showing evidence of resistance to antibiotic · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Antibiotic vs control Adverse effects · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 9 studies · 1961 participants | Low |
Oral vs topical antibiotic Active trachoma Clinical assessment: active trachoma defined as TF, TI, or both · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | RR 0.97 [0.81, 1.16] | 6 studies · 953 participants | Low |
Oral vs topical antibiotic Ocular C trachomatis infection Positive test for C trachomatis infection identified by culture, staining on conjunctival smears, or nucleic acid amplification methods · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 3 studies · 298 participants | Very low |
Oral vs topical antibiotic Antibiotic resistance Proportion of samples showing evidence of resistance to antibiotic · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral vs topical antibiotic Adverse effects · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | 8 studies · 1583 participants | Low |
Oral azithromycin vs control Active trachoma Clinical assessment: active trachoma defined as TF, TI, or both · people (any age) with active trachoma Antibiotics for trachoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings: anti‐VEGF treatment vs control Gain of 15 or more letters visual acuity at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 4.19 [2.32, 7.55] | 6 studies · 2667 participants | Moderate |
Summary of findings: bevacizumab vs ranibizumab Mean change in visual acuity at 1 year (number of letters) · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | no estimate extracted | 9 studies · 3190 participants | High |
Summary of findings: bevacizumab vs ranibizumab Reduction in central retinal thickness at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | no estimate extracted | 6 studies · 2693 participants | High |
Summary of findings: bevacizumab vs ranibizumab No problems in quality of life domains at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 0.96 [0.9, 1.04] | 1 study · 548 participants | Moderate |
Summary of findings: bevacizumab vs ranibizumab Serious systemic adverse events at 1 yearb · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 1.15 [0.99, 1.34] | 6 studies · 3365 participants | Moderate |
Summary of findings: bevacizumab vs ranibizumab Serious ocular adverse events at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 0.51 [0.05, 5.62] | 1670 participants | Moderate |
Summary of findings: anti‐VEGF treatment vs control Loss of fewer than 15 letters visual acuity at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 1.4 [1.27, 1.55] | 6 studies · 2667 participants | High |
Summary of findings: anti‐VEGF treatment vs control Mean change in visual acuity at 1 year (number of letters) · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | no estimate extracted | 4 studies · 2508 participants | Moderate |
Summary of findings: anti‐VEGF treatment vs control Reduction in central retinal thickness at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings: anti‐VEGF treatment vs control Mean change in vision‐related quality of life · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | MD 6.69 [3.38, 9.99] | 2 studies · 1134 participants | Moderate |
Summary of findings: anti‐VEGF treatment vs control Serious systemic adverse events at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 0.17 [0.01, 4.24] | 6 studies · 2667 participants | Moderate |
Summary of findings: anti‐VEGF treatment vs control Serious ocular adverse events at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 0.52 [0.03, 8.25] | 6 studies · 2667 participants | Moderate |
Summary of findings: bevacizumab vs ranibizumab Gain of 15 or more letters visual acuity at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 0.95 [0.81, 1.12] | 8 studies · 3144 participants | High |
Summary of findings: bevacizumab vs ranibizumab Loss of fewer than 15 letters visual acuity at 1 year · people with neovascular age‐related macular degeneration Anti‐vascular endothelial growth factor for neovascular age‐related macular degeneration (2019) · Cochrane | RR 1 [0.98, 1.02] | 8 studies · 3144 participants | High |
Conventional occlusion vs atropine penalization Mean visual acuity at 6 months (difference in LogMAR units between occlusion and atropine groups) · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 3 studies · 552 participants | Moderate |
Conventional occlusion vs atropine penalization Mean visual acuity at 24 months (difference in LogMAR units between occlusion and atropine groups) · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 2 studies · 483 participants | Moderate |
Conventional occlusion vs atropine penalization Adherence to treatment (different measures and time points reported in the included studies) Assessed at different time points (6, 12, 0r 24 months), and with different measures (percentage of prescribed treatment that was completed at each study ... · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 4 studies · 588 participants | Moderate |
Conventional occlusion vs atropine penalization Ocular alignment (different measures and time points reported in the included studies) Assessed at different time points (17 weeks, 24 months, or cessation of treatment) and by the proportions of participants who developed strabismus, showed chang... · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 3 studies · 888 participants | Moderate |
Conventional occlusion vs atropine penalization Stereo acuity (different measures and time points reported in the included studies) Assessed at different time points (17 weeks, 6 months, 2 years, or at cessation of treatment) and using different measures (TNO stereo test, Titmus fly test, Rando... · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 5 studies · 865 participants | Moderate |
Conventional occlusion vs atropine penalization Quality of life (different measures and time points reported in the included studies) Assessed at different time points (17 weeks or 6 months) by patient preference or the Amblyopia Treatment Index questionnaire. · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 2 studies · 256 participants | Moderate |
Conventional occlusion vs atropine penalization Adverse events (reported occurrence of: mild reduction in the visual acuity of the sound eye not requiring treatment; light sensitivity; skin, lid, or conjunctival irritation) Assessed at different time points (17 weeks or 2 years). · Participants of any age with either unilateral strabismic, anisometropic, or mixed (strabismic‐refractive) amblyopia;… Conventional occlusion versus pharmacologic penalization for amblyopia (2019) · Cochrane | no estimate extracted | 2 studies · 612 participants | High |