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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.
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 |
|---|---|---|---|
Routine preoperative medical testing vs selective or no testing Medical adverse events up to 2 months after surgery · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | OR 1 [0.86, 1.16] | 3 studies · 21531 participants | High |
Routine preoperative medical testing vs selective or no testing Ocular adverse events up to 2 months after surgery · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | OR 0.99 [0.71, 1.38] | 2 studies · 2281 participants | Moderate |
Routine preoperative medical testing vs selective or no testing Cost for preoperative testing prior to surgery · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | no estimate extracted | 1 study · 1005 participants | Moderate |
Routine preoperative medical testing vs selective or no testing Cancellation of cataract surgery prior to surgery · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | OR 0.97 [0.78, 1.21] | 2 studies · 20582 participants | High |
Routine preoperative medical testing vs selective or no testing Clinical management changes (other than cancellation) prior to surgery · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Routine preoperative medical testing vs selective or no testing Quality of life outcomes at any · adults with age‐related cataract Routine preoperative medical testing for cataract surgery (2019) · Cochrane | no estimate extracted | NR | No studies |
Pars plana vitrectomy (PPV) vs scleral buckling Primary retinal reattachment at least 3 months after operation · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | RR 1.07 [0.98, 1.16] | 9 studies · 1261 participants | Low |
Pars plana vitrectomy (PPV) vs scleral buckling Postoperative visual acuity (logMAR) range 0 to 2; higher values of logMAR indicate worse visual acuity at least 3 months after operation · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | no estimate extracted | 6 studies · 1138 participants | Low |
Pars plana vitrectomy (PPV) vs scleral buckling Final anatomical success at least 3 months after operation · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | RR 1.01 [0.99, 1.04] | 9 studies · 1235 participants | Low |
Pars plana vitrectomy (PPV) vs scleral buckling Recurrence of retinal detachment at least 3 months after operation · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | RR 0.75 [0.59, 0.96] | 9 studies · 1320 participants | Low |
Pars plana vitrectomy (PPV) vs scleral buckling Number of interventions needed to achieve final anatomical success at final · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | no estimate extracted | 2 studies · 682 participants | Very low |
Pars plana vitrectomy (PPV) vs scleral buckling Quality of life (satisfaction with vision) at least 3 months after operation · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | RR 6.22 [0.88, 44.09] | 1 study · 32 participants | Very low |
Pars plana vitrectomy (PPV) vs scleral buckling Adverse effects (cataract development, choroidal detachment, new/iatrogenic breaks, postoperative proliferative vitreoretinopathy, postoperative increase in intraocular pressure, development of cystoid macular oedema, macular pucker, strabismus) a... · people with simple rhegmatogenous retinal detachments Pars plana vitrectomy versus scleral buckling for repairing simple rhegmatogenous retinal detachments (2019) · Cochrane | OR 1.71 | 1 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Subjective symptoms of dry eye at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 1 study · 56 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Ocular surface dye staining at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 2 studies · 291 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Aqueous tear production measured by Schirmer test scores (mm/5 minutes) at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 4 studies · 406 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Tear film stability measured by tear break‐up time (seconds) at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 5 studies · 676 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Frequency of artificial tear usage at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 3 studies · 910 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Conjunctival goblet cell density (cells per unit) at 6 months · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 2 studies · 100 participants | Low |
Topical cyclosporine A 0.05% + artificial tears vs vehicle + artificial tears or artificial tears alone Treatment related adverse events, · People with dry eye syndrome Topical cyclosporine A therapy for dry eye syndrome (2019) · Cochrane | no estimate extracted | 3 studies · 743 participants | Low |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Change in dry eye symptoms, measured using the OSDI score (ranging from 0 to 100 units, with a reduction in scores indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 7 studies · 1785 participants | Low |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Change in tear film stability, measured using tear break‐up time (TBUT) with fluorescein (in seconds, with higher scores indicating greater tear film stability) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | MD 0.55 | 4 studies · 455 participants | Moderate |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Change in tear osmolarity (measured in mOsmol/L, with reductions in osmolarity indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 1 study · 83 participants | Low |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Adverse event: gastrointestinal disorders at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 1 study · 138 participants | Low |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Dry eye symptoms, measured using the OSDI score (ranging from 0 to 100 units, with a reduction in scores indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 2 studies · 70 participants | Low |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Change in ocular surface staining at 1‐month · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Change in Schirmer test (aqueous tear production, measured in mm/5 min) at 1‐month of · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Change in tear film stability, measured using tear break‐up time (TBUT) with fluorescein (in seconds) at 1‐month · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Change in tear osmolarity (measured in mOsmol/L, with reductions in osmolarity indicating clinical improvement) at 1‐month · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral omega‐3 PUFAs plus conventional therapy vs conventional therapy alone Adverse events at 1‐month · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | NR | No studies |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Change in dry eye symptoms, measured using the OSDI score (ranging from 0 to 100 units, with a reduction in score indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 4 studies · 1144 participants | Moderate |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Change in ocular surface staining at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | MD 0.1 | 4 studies · 681 participants | Low |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Change in ocular surface staining at 1‐month · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 4 studies · 709 participants | Low |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Change in Schirmer test (aqueous tear production, measured in mm/5 min, with higher scores indicating more tear production) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | MD 2.6 | 5 studies · 1205 participants | Low |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Change in tear film stability, measured using tear break‐up time (TBUT) with fluorescein (in seconds, with higher scores indicating greater tear film stability) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 5 studies · 1205 participants | Low |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Change in tear osmolarity (measured in mOsmol/L, with reductions in osmolarity indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 1 study · 105 participants | Low |
Oral long‐chain omega‐3 PUFAs vs oral omega‐6 PUFAs Adverse event: gastrointestinal disorders at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | RR 2.34 | 2 studies · 91 participants | Low |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Change in Schirmer test (aqueous tear production, measured in mm/5 min, with higher scores indicating more tear production) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | MD 0.68 | 7 studies · 1730 participants | Moderate |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Change in tear film stability, measured using tear break‐up time (TBUT) with fluorescein (in seconds, with higher scores indicating greater tear film stability) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 5 studies · 1640 participants | Low |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Change in tear osmolarity (measured in mOsmol/L, with reductions in osmolarity indicating clinical improvement) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 1 study · 54 participants | Low |
Oral long‐chain omega‐3 PUFAs (ie, EPA and DHA) vs placebo or no treatment Adverse event: gastrointestinal disorders at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 3 studies · 719 participants | Low |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Symptoms of dry eye at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 4 studies · 4 participants | Low |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Ocular surface staining at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | no estimate extracted | 3 studies · 3 participants | Moderate |
Combined oral omega‐3 and omega‐6 PUFAs vs placebo Schirmer test (aqueous tear production, measured in mm/5 min, with higher scores indicating more tear production) at 1‐month (with actual · people with dry eyea Omega‐3 and omega‐6 polyunsaturated fatty acids for dry eye disease (2019) · Cochrane | MD 0.66 | 4 studies · 455 participants | Moderate |
Aqueous shunts with vs without mitomycin C Mean IOP (mmHg) · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | 3 studies · 78 participants | Low |
Aqueous shunts with vs without mitomycin C Control of IOP, assessed as the mean decrease in IOP from baseline · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Aqueous shunts with vs without mitomycin C Mean change from baseline in visual acuity · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Aqueous shunts with vs without mitomycin C Proportion of participants with stable best‐corrected visual acuity · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Aqueous shunts with vs without mitomycin C Proportion of participants with decreased visual acuity · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | NR | No studies |
Aqueous shunts with vs without mitomycin C Proportion of participants with a postoperative hypertensive phase · adults with glaucoma requiring aqueous shunt surgery Aqueous shunts with mitomycin C versus aqueous shunts alone for glaucoma (2019) · Cochrane | no estimate extracted | NR | No studies |