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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)

75,239 questions in 5,342 reviews

current versions
No studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%

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
Refusal to participate (participation rates of consumers) · Patients with Gulf War veterans' illness
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 1092 participantsLow
Intervention NR
MD: Mean difference · Mental health patients
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Healthcare priorities (consumer influence on decisions) · Consumers of a community organization
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 29 participantsVery low
Intervention NR
Anxiety (consumer influence on healthcare outcomes) · patients undergoing endoscopy or patients who receive PCA
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted2 studies · 335 participantsModerate
Intervention NR
Satisfaction with information material (consumers' satisfaction with products resulting from consumer involvement) · patients undergoing endoscopy or patients who receive PCA
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted2 studies · 335 participantsModerate
Intervention NR
Knowledge of patient‐controlled analgesia (consumer influence on healthcare outcomes) · patients undergoing endoscopy or patients who receive PCA
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 100 participantsModerate
Intervention NR
Understanding (consumer influence on healthcare outcomes) Informed Consent Questionnaire‐4. Scale from: 0 to 1. ( · Patients with Gulf War veterans' illness
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 1092 participantsLow
Intervention NR
Satisfaction (consumer satisfaction resulting from consumer involvement) · Patients with Gulf War veterans' illness
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 1092 participantsLow
Intervention NR
Adherence (participation rates of consumers) · Patients with Gulf War veterans' illness
Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane
no estimate extracted1 study · 1092 participantsLow
Intervention NR
Number of ARTIs · children (age < 18 years) susceptible to acute respiratory tract infections (ARTIs)
Immunostimulants for preventing respiratory tract infection in children (2006) · Cochrane
no estimate extracted35 studies · 4060 participantsModerate
Intervention NR
Percent difference in ARTIs · children (age < 18 years) susceptible to acute respiratory tract infections (ARTIs)
Immunostimulants for preventing respiratory tract infection in children (2006) · Cochrane
no estimate extracted35 studies · 4060 participantsModerate
Intervention NR
Incidence of gastrointestinal adverse events · children (age < 18 years) susceptible to acute respiratory tract infections (ARTIs)
Immunostimulants for preventing respiratory tract infection in children (2006) · Cochrane
no estimate extracted10 studies · 1457 participantsLow
Intervention NR
Incidence of skin adverse events · children (age < 18 years) susceptible to acute respiratory tract infections (ARTIs)
Immunostimulants for preventing respiratory tract infection in children (2006) · Cochrane
no estimate extracted10 studies · 1469 participantsLow
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery)
Change in clinical attachment level (attachment gain) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
MD 1.25 [0.89, 1.61]2 studiesUngraded
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery)
Change in probing depth (probing depth reduction) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
MD 1.21 [0.53, 1.88]11 studiesUngraded
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery)
Disease recurrence (% sites with >=2 mm loss of probing attachment from 12 months after treatment) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved…
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes').0 studiesNo studies
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium)
Air blast sensitivity · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks
Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane
SMD -1.25 [-1.65, -0.85]6 studies · 392 participantsUngraded
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery)
Ease of maintenance (% of sites with <4 mm probing depth) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved…
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes').0 studiesNo studies
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium)
Tactile sensitivity (method b, continuous probe) · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks
Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane
SMD 1.19 [0.79, 1.59]5 studies · 356 participantsUngraded
Tongue scraping (mechanical tongue cleaning) vs Mouthwash or other chemical intervention
Outcome NR · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned)
Tongue scraping for treating halitosis (2006) · Cochrane
No randomized controlled trials comparing mechanical tongue cleaning with mouthwashes were identified; the review notes "the somewhat unexpected lack of randomized controlled trials comparing the effectiveness of…0 studiesNo studies
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery)
Change in probing depth (probing depth reduction) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
MD 1.24 [0.89, 1.59]2 studiesUngraded
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery)
Change in gingival recession · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
MD -0.33 [-0.43, -0.23]1 studyUngraded
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery)
Patient well-being / quality of life · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved…
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
Cortellini 2001: 36% of GTR patients reported the procedure interfered with daily activity for an average of 2.7 days versus 32% of controls for an average of 2.4 days; no significant difference for postoperative pain…1 studyUngraded
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery)
Post-operative complications / adverse effects (including pain, infection) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved…
Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane
Adverse effects were generally minor. Healing was generally uneventful for both test and control groups. Exposure of the GTR barrier membrane was widely reported, ranging from 20% of sites (non-resorbable…16 studiesUngraded
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless)
Number of denture adjustments required · Edentulous adult patients requiring complete dentures · 3 weeks per denture set (cross-over)
Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane
No statistically significant difference was found between the two occlusal patterns with regard to the number of adjustments required.1 study · 30 participantsUngraded
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless)
Patient perceived comfort · Edentulous adult patients requiring complete dentures
Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane
no estimate extractedNRNo studies
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless)
Patient perceived masticatory/chewing efficiency · Edentulous adult patients requiring complete dentures
Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Mortality · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
RR 0.7 [0.42, 1.15]8 studies · 2574 participantsModerate
Intervention NR
Pneumonia‐specific mortality · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
RR 0.57 [0.24, 1.37]4 studies · 723 participantsModerate
Intervention NR
Duration of pneumonia · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
no estimate extracted2 studies · 249 participantsModerate
Intervention NR
Duration of diarrhea in days · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
no estimate extracted2 studies · 249 participantsModerate
Intervention NR
Hospital stay in days · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
no estimate extracted2 studies · 278 participantsModerate
Intervention NR
Duration of fever in days · children with measles
Vitamin A for treating measles in children (2005) · Cochrane
no estimate extracted2 studies · 149 participantsModerate
Intervention NR
Trabeculectomy failure at 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
RR 0.37 [0.26, 0.51]11 studies · 698 participantsModerate
Intervention NR
mean intraocular pressure mmHg at 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
no estimate extracted380 participantsModerate
Intervention NR
complications wound leak by 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
RR 1.84 [0.72, 4.66]7 studies · 333 participantsLow
Intervention NR
complications hypotony occurring up to 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
RR 1.8 [0.79, 4.12]10 studies · 488 participantsLow
Intervention NR
complications shallow anterior chamber occurring within 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
RR 1.14 [0.42, 3.07]10 studies · 441 participantsLow
Intervention NR
cataract formation by 12 months · People undergoing trabeculectomy surgery with glaucoma
Intraoperative Mitomycin C for glaucoma surgery (2005) · Cochrane
RR 1.8 [1, 3.22]7 studies · 482 participantsModerate
Intervention NR
Pain based on WOMAC pain scale Scale from: 0 (no pain) to 20 (worst pain). ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted11 studies · 2173 participantsModerate
Intervention NR
WOMAC Function Subscale Scale from: 0 to 68. ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted9 studies · 2017 participantsHigh
Intervention NR
Physician Global Assessment 100 mm visual analogue scale. Scale from: 0 to 100. ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted1 study · 630 participantsModerate
Intervention NR
Patient Global Assessment (patients rated whether they were better at the end of trial than at the start of the trial) ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
RR 1.21 [0.8, 1.82]1 study · 118 participantsModerate
Intervention NR
Minimum Joint Space Width mm ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted2 studies · 414 participantsHigh
Intervention NR
Toxicity (Number of Patients Reporting Adverse Events) · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
RR 0.99 [0.91, 1.07]9 studies · 1640 participantsHigh
Intervention NR
Toxicity (Number of Withdrawals due to Adverse Events) · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
RR 0.76 [0.54, 1.07]12 studies · 2435 participantsModerate
Intervention NR
Pain based on WOMAC scale Scale from: 0 (no pain) to 20 (worst pain). ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted8 studies · 940 participantsLow
Intervention NR
WOMAC Function Subscale Scale from: 0 to 68. ( · patients with treating osteoarthritis
Glucosamine therapy for treating osteoarthritis (2005) · Cochrane
no estimate extracted3 studies · 624 participantsHigh
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless)
Patient perceived satisfaction (denture preference) · Edentulous adult patients requiring complete dentures · 3 weeks per denture set (cross-over)
Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane
OR 10 [2.04, 48.96]1 study · 30 participantsUngraded
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless)
Patient perceived masticatory/chewing function · Edentulous adult patients requiring complete dentures
Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane
no estimate extractedNRNo studies