Open label, single group, uncontrolled10 | Preservative-free hypoosmolar (280 mOsm/L) copolymer, commercially available in Italy (Farmigea, Pisa, Italy); contains 0.2% hyaluronic acid and 0.2% tamarind seed polysaccharide, pH 7.4; 3 times daily on waking with no lens, early afternoon and before bed with lenses in | CLD as measured by OSDI | OSDI > 12; tear breakup time (TBUT) ≤ 10; Schirmer 1 > 10 mm | 15 | 60 d | Weak; high risk of bias (uncontrolled; placebo effect very likely) |
Crossover, investigator masked11 | Verbal and written instructions for using a no-rubbing, rinsing lens care regimen following the manufacturer's recommendations | CLD as measured by OSDI | Habitual soft contact lens daily wear for at least the past 6 mo, asymptomatic and satisfied with the vision and comfort of the habitual lenses | 72 (65 completed) | 10-wk study: 1-wk accrual (adaptation) followed by 2-wk trial × 3 conditions with 1-wk washout between conditions | Weak; high risk of bias (nonvalidated secondary outcome measures, industry funded, bias due to inadequate randomization likely) |
Open-label, parallel-group, randomized trial12 | Azithromycin: 1 drop to each eye twice a day for the first 2 d, then 1 drop daily for days 3–29 applied in the morning before contact lens application Visine for contacts: 1–2 drops 4 times a day for 29 d spaced by approximately 4 h on each dosing | Comfortable contact lens daily wear time (CFB) at week 4 (average of days 23–29) | CLDEQ ≥ 2 | 50 (25 per arm) | 4 wk (29 d) | Moderate; intermediate risk of bias (open label), unbalanced, comfortable wear times at baseline may have favored treatment arm) |
Open label, single group, uncontrolled, crossover13 | Lotrafilcon A was worn, and fit was assessed by observer and by subjective comfort. 8.60 BC,* then 8.40 BC only if fit unsuccessful with 8.60 BC. | Objective assessment of fit and subjective comfort rate (1–10 scale) after 1 and 15 min (lens settling) | Habitual lens wearers | 95 subjects (190 eyes), 49 eyes fitted with second lens | 6-mo study but paper presents nondispensing fitting data only, 15 min | Weak; high risk of bias (data from 2 eyes of 1 subject considered independent; uncontrolled, unbalanced, industry funded) |
Randomized, double-masked, contralateral study14 | Asymptomatic group: Focus Night & Day (CIBA Vision, Atlanta, GA) vs. Acuvue 2 (Johnson and Johnson Vision Care, Jacksonville, FL). | Ocular comfort on 0–100 rating scale | Habitual lens wearers | 39 subjects; 20 asymptomatic lens wearers and 19 symptomatic lens wearers | 7 h | Moderate; moderate risk of bias (partly industry funded, no run-in prior to enrolment) |
Symptomatic group: Focus Night & Day vs. Acuvue 2 (Johnson and Johnson Vision Care) and Focus Dailies (CIBA Vision) vs. Proclear Compatibles (CooperVision, Pleasanton, CA). |
Randomized single masked, using deception as control15 | Habitual daily wear hydrogel lens wearers were refitted with lotrafilcon A (Focus Night & Day; CIBA Vision) but told they were randomly assigned to wear either low-oxygen or high-oxygen permeability lenses and were “masked” to lens assignment. | Subjective comfort and dryness VAS (0–100) | Habitual lens daily wear with >4 y experience | 87 (81 analyzed) | 2 mo | Moderate; high risk of bias (open label, habitual lens wear preintervention control likely to favor intervention; analysis not intention to treat; care regimen a potential confounder; industry funded) |
Randomized, contralateral, crossover study, open label16 | Hioxifilcon A lenses (extreme H2O, copolymer GMA-HEMA), diameter 14.2 mm, base curve 8.6-mm, center thickness at 3.00 diopter 0.07 mm, 59% water content, Group 2, high-water nonionic, cast-molded daily wear with fortnightly replacements. Omafilcon A (Proclear Compatibles; CooperVision), diameter 14.2 mm, BC 8.2 or 8.5 mm, center thickness at 3.00 D 0.065 mm, 59% water content, Group 2, high-water nonionic, cast-molded. OPTI-FREE Express (Alcon Laboratories) disinfection solution and Clerz Plus Lens Drops (Alcon Laboratories). Patient switched to hydrogen peroxide if solution problems suspected (number not specified) | CLDEQ (frequency and severity of dryness, discomfort, and blurry vision) | Previous diagnosis of mild to moderate dry eye or thinking one has dry eye or symptoms of dry eye AND either tear breakup time < 10 s, Schirmer 1 test ≤ 5 mm, staining ≥ 1, or bulbar redness | 40 | 6 wk in each arm (crossover), 12 wk total | Moderate; high risk of bias (open label, habitual lens wear preintervention control; use of baseline habitual lens wear control may have favored treatment arms; no washout) |
Study 1: multicenter prevalence study Study 2: uncontrolled, single-masked (subjects) intervention study17 | Study 1: NA Study 2: senofilcon A daily wear lens for 2 wk Continuing with habitual lens care unless advised by investigator (unspecified) | Discomfort: 4-point scale (never, infrequent, frequent, constant) | Problem contact lens patients: difference of >2 h between average and comfortable wear time OR frequent or constant discomfort or dryness symptoms on CLDEQ OR limbal or bulbar hyperemia ≥ 2 OR corneal staining ≥ 3 | Study 1: 1092 Study 2: 257 | Study 1: NA Study 2: 2 wk | Moderate; high risk of bias (no washout; trial short; comparison to habitual lens wear control subject to bias; questionable external validity) |
Randomized, controlled (no treatment), investigator-masked clinical study 18 | Unpreserved 0.9% sodium chloride (Hydrabak; Laboratoires Thea, Clermont-Ferrand, France) in both eyes 4 times a day for 21 d. All subjects used the same contact lens care solution (type unspecified). | Ocular comfort: 0–100 continuous VAS with anchors “excellent (lenses not felt)” at one end and “very uncomfortable (lenses cause irritation or discomfort)” at the other | Experiencing ocular discomfort (irritation, stinging, burning , or sensation of intermittent blurred vision), TBUT ≥10 s, Schirmer 1 ≥ 5 mm in 5 min in both eyes | 50; 30 randomized to intervention, 20 to control | 21 d | Weak; high risk of bias (no washout; trial short; comparison vs. baseline; lacking no-treatment control; confounders not measured) |
Study 1: prospective cross-sectional (3 groups). Study 2: randomized, contralateral, open label, no-treatment control 19 | Study 1: etafilcon A 8.5-mm base curve (Acuvue 1-Day; Johnson and Johnson Vision Care) Study 2: 20-μL ReNu MultiPlus (Bausch & Lomb, Rochester, NY) rewetting drop | Ocular comfort: 0–50 continuous VAS | Study 2 Symptomatic: self-reporting of at least 1 symptom often or continually on Shippai Eye Study20 Dry Eye Questionnaire | 60 (20 per arm) | Study 1: 10 h Study 2: 30 min | Strong; low risk of bias (no washout; primary outcome poorly described (anchors and descriptors not specified) |
Single masked (subject), contralateral, no-treatment control21 | 2 drops of sterile, isotonic, buffered, solution of carboxymethylcellulose (CMC), sodium chloride, boric acid, potassium chloride, calcium chloride, magnesium chloride, purified water and preserved with PURITE (stabilized oxychlororcomplex) 0.005% (Refresh Contacts; Allergan, Inc., Irvine, CA) on back surface of contact lens prior to insertion vs. straight from packaging in contralateral eye | Ocular comfort on 0–100 rating scale | At least 1 mo of lens wear Symptomatic lens wearers based on answering “no” to “Are you able to wear your lenses for as long as you want?" | 61 (59 analyzed): 12 symptomatic, 49 asymptomatic | 8 h | Weak; high risk of bias (2 authors employed by industry; investigator not masked; no washout; unequal arms; analysis not ITT; some data [e.g., comfort] not presented) |
Crossover, single masked (investigator)22 | OPTI-FREE Express Lasting Comfort No Rub Formula (Alcon Laboratories) vs. ReNu MultiPlus (Bausch & Lomb) | Comfort (0–100 VAS) | At least 1 y of lens wear, 8 h/d | 8 | 4 wk | Weak; high risk of bias (no washout; not randomized; sample size too low; confounders not controlled [e.g., lens type]) |
Multisite, uncontrolled, open label23 | Nelfilcon A containing high molecular weight, nonfunctionalized polyvinyl alcohol (PVA) and packaging saline containing hydroxypropyl methylcellulose and polyethylene glycol (Triple Action Moisture DAILIES AquaComfort Plus; CIBA Vision) worn daily on daily disposable schedule | Frequency and severity of 8 common subjective symptoms (tired eyes, irritated eyes, lens awareness, blurred vision, redness, discomfort, deposits, dryness) | Contact lens wearer reporting at least 2 symptoms often or always | 83 (81 completed) | 4 wk | Weak; high risk of bias (use of baseline habitual lens wear comparison may have favored treatment arm; no washout; industry sponsored, conducted, written) |
Randomized, controlled, double-masked, single-center clinical trial24 | 3-mo absorbable glycolic acid and trimethylene carbonate punctual plug (EXTEND Absorbable Synthetic Implants; Odyssey Medical, Memphis, TN) vs. sham procedure | CLDEQ | Symptomatic dry eye contact lens wearers with CLDEQ score > 0.1325 | 32 enrolled, 22 eligible based on CLDEQ score, 19 completed | 6 wk | Strong; low risk of bias (sham procedure and blinding well described; regression toward the mean and placebo effect likely) |
Randomized, investigator masked, placebo controlled26 | Cyclosporine 0.05% ophthalmic emulsion (Restasis; Allergan, Inc.) twice per day vs. rewetting drops (carboxymethylcellulose 0.5%, Refresh Contacts; Allergan, Inc.), twice per day, to be used before and after lens wear | Subjective evaluation of dryness severity (mild, moderate, severe), OSDI | Self-reported history of contact lens dryness/intolerance | 17 | 5 wk | Medium; moderate risk of bias (patients unmasked; subjective bias likely); demographic data not provided |
Randomized, double masked, placebo controlled39 | Cyclosporine 0.05% ophthalmic emulsion vs. Refresh Preservative Free Artificial Tears (Allergan, Inc.) twice a day | OSDI and National Eye Institute Refractive Error Quality of Life Instrument | Chart review to identify contact lens wearers with complaints of dryness including irritation, burning, decreased wearing time | 44 (22 per arm) | 3 mo | Strong; low risk of bias (continuing use of habitual lens and cleaning regimen potential confounder; no washout) |
Randomized, double-blind, parallel-group 15- center study27 | 2% polyvinylpyrrolidone (PVP) vs. 0.9% NaCl 1–6 drops per day as required | Overall contact lens comfort (VAS scale) | Contact lens wearers complaining of discomfort and soreness, irritation, smarting, burning, blurred vision aggravated by environmental factors (air conditioning, heating, working conditions, e.g., prolonged use of visual display unit) | 45 (25 PVP, 20 NaCl) | 28 d | Weak; high risk of bias (unbalanced; industry sponsored, conducted, written; variable dosage confounder) |
Single-center, double-masked, randomized, crossover, pilot clinical trial28 | Senofilcon A (Acuvue Oasys with Hydraclear Plus; Johnson and Johnson Vision Care) vs. habitual (control) during 75-min controlled adverse environment (CAE) exposure | Ocular discomfort (0–4 scale) | Soft contact lens wearers with histories of ocular discomfort during lens wear in windy or dry environments | 11 | 75 min | Weak; high risk of bias (use of habitual lens wear control a potential confounder; inadequate sample size; masking not described; industry funded) |
Randomized, contralateral, crossover, open-label clinical trial29 | Intervention 1: etafilcon A (1-DAY Acuvue; Johnson & Johnson Vision Care) vs. lotrafilcon A (NIGHT & DAY; CIBA Vision) | Comfort (100-point scale) | At least 12 mo of lens wear fitted | 15 | 6 h on 4 separate days | Moderate; moderate risk of bias (patients masked for lens type but unmasked for drop type except at insertion; investigators not masked) |
Intervention 2: NaCl 90 mg/mL (AstraZeneca, North Ryde, NSW, Australia) vs. PVA 14 mg/mL, povidone 6 mg/mL, sodium chloride (Refresh; Allergan, Inc.) vs. carboxymethylcellulose (CMC) 5 mg/mL (Cellufresh; Allergan, Inc.) every 2 h for 6 h |
Prospective, single-masked (subjects), randomized, crossover study30 | Lotrafilcon A with hypoosmotic (280 mmol/kg) vs. hyperosmotic (380 mmol/kg) saline 15 μL 4 times a day | Comfort (1–100 scale) | Symptomatic lens wearers with maximum comfortable wearing time < 6 h | 15 | 6 h | Strong; low risk of bias (investigator not masked) |
Randomized, controlled, double-masked, 19-site study31 | OPTI-FREE RepleniSH (Alcon Laboratories) vs. ReNu MultiPlus No Rub Formula (Bausch & Lomb) | Comfort and dryness scores (0–100 scale) | Symptomatic wearers of group IV soft lenses answering disagree or strongly disagree to “My contacts are comfortable all day long” and agree or strongly agree to one or both of “During the day, I take my contacts out earlier than I like because they become uncomfortable” and “Late in the day, my contacts become uncomfortable but I continue wearing them” | 362 (183 OPTI-FREE vs. 179 ReNu MultiPlus) | 28 d | Medium; moderate risk of bias (no washout; lens type solution interactions likely confounder) |
Randomized, crossover study, open label32 | Omafilcon A (Proclear; CooperVision) vs. new habitual lenses (control) | Subjective symptoms VAS (10 cm) scale (comfort and dryness severity; dryness, eye irritation, itchiness, burning, soreness, scratchiness, grittiness, watering, light sensitivity frequency) | Contact lens wearers with dry eyes (NEI definition: Schirmer without anesthesia ≤ 5 mm, rose bengal staining ≥ 3, fluorescein staining ≥ 3, meibomian gland dysfunction ≥ 2) | 76 | 6-wk crossover | Weak; high risk of bias (open label likely to favor new lens type; use of more than 1 lens type as control a confounder; industry funded) |
Randomized, double-masked, cross-over study33 | Lotrafilcon B with polyhexamethylene biguanide (PHMB) (Solocare Aqua; CIBA Vision) vs. PHMB with surfactant (Hidro Health, Disop, Spain) solutions | 10-item symptoms questionnaire (0–10 scale): discomfort, blurry vision, lens-handling problems, dryness, redness, tearing, burning, itching, discharge, dissatisfaction + CLDEQ | Daily wear of lotrafilcon B for >3 mo | 54 | 1-mo crossover | Strong; low risk of bias |
Randomized, crossover, single masked (participant)34 | 5 silicone hydrogels: galyfilcon A (Acuvue Advance; Johnson & Johnson Vision Care); senofilcon A (Acuvue OASYS; Johnson & Johnson Vision Care); lotrafilcon B (O2Optix; CIBA Vision); lotrafilcon A (NIGHT & DAY; CIBA Vision); balafilcon A (PureVision; Bausch & Lomb) disinfected with ClearCare (AOSept Plus; CIBA Vision) for >6 h | Comfort, burning, dryness, analogue scales (0–100) with verbal anchors at various times (insertion, settling, 8 h, 12 h on days 1, 4, 7, 10, and 14 using handheld wireless communication devices | Adapted soft lens wearers | 55 (45 completed and analyzed) | 4-wk crossover with 1 d washout | High; low risk of bias (base curve selection for 2 of 5 lens types a potential confounder; single masked only) |
Retrospective multistudy, multicenter analysis, open label, uncontrolled9 | Lotrafilcon A (NIGHT & DAY; CIBA Vision) or lotrafilcon B (O2Optix; CIBA Vision) daily wear or continuous | Dryness during the day and end-of-day from CLDEQ | Adapted soft lens wearers (nonsilicone hydrogel) | 259 | 2 wk (lotrafilcon B) or 1 mo (lotrafilcon A) | Weak; high risk of bias (open label; subject masked to study sponsor only, not to lens type; retrospective; uncontrolled; multiple wear schedule and lens type a confounder) |
Contralateral, randomized, double masked35 | Etafilcon A (Acuvue; Johnson and Johnson Vision Care) vs. Omafilcon A (Proclear Biocompatibles; CooperVision) | Subjective comfort and dryness (100-mm VAS scale with anchors at 0 = very dry and 100 = no dryness) at 0, 1, 3, 5, and 7 h | Symptomatic: Wearers with symptoms of dryness after 5 h of wear with consequently reduced wearing time and use of lubricating drops at least once daily | 40 (20 symptomatic, 20 asymptomatic) | 7 h | Moderate; moderate risk of bias (no washout; contralateral eye effect potential confounder) |
Asymptomatic: wearers without symptoms of dryness or discomfort who could wear lenses all day without use of lubricants |
Randomized, investigator-masked, crossover study36 | Hydroxypropyl methylcellulose (HPMC) (COMPLETE ComfortPLUS; Allergan, Inc.) vs. citrate (No Rub OPTI-FREE Express; Alcon Laboratories) solution with fresh habitual lenses | Daytime and end-of-day comfort and dryness (50-point continuous scale with anchors 0 = impossible to wear and 50 = excellent) | Experienced daily lens wearers | 75 (64 completed) | 1-mo crossover with 1-wk washout | Moderate; moderate risk of bias (participants masked only to study sponsor; lens type confounder, industry funded) |
Retrospective, 7-study open-label trial37 | Senofilcon A (Johnson & Johnson Vision Care) daily wear with multipurpose solution (MPS) (one of Polyquad/EDTA, Alcon Laboratories; Polyquad/nonanoyl-EDTA, Alcon Laboratories; PHMB/borate, Bausch & Lomb; PHMB/phosphate, CIBA Vision) vs. hydrogen peroxide (H2O2) vs. daily disposable (DD) | Comfort and dryness on a 1–10 scale with anchors 1 = poor and 10 = excellent | Previous wear experience not specified | 283 (160 MPS, 83 H2O2, 40 DD) | 3 mo | Weak; high risk of bias (open label; not randomized; retrospective; multiple MPS and replacement schedule confounders; unbalanced; same participants in more than 1 trial) |
Randomized, investigator-masked, 2-site crossover study38 | No Rub OPTI-FREE Express (Alcon Laboratories) vs. Complete (Allergan, Inc.) or ReNu MultiPlus (Bausch & Lomb) with Acuvue 2 (Johnson and Johnson Vision Care) or Softlens 66 (Bausch & Lomb) | Subjective preference based on answer to “Did you notice a difference in comfort provided by the study solutions?” | Daily wearers | 89 (47 and 42 at each site); 71 completed | 2-mo crossover with 72-h washout | Weak; high risk of bias (participants not masked; unequal group sizes; randomization not stratified by site) |