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.

Limit to evidence status or GRADE (optional)

1,518 questions in 135 reviews · Infectious Diseases

current versions
No studies 135 · 8.9%Ungraded 150 · 9.9%Very low 350 · 23.1%Low 420 · 27.7%Moderate 321 · 21.1%High 142 · 9.4%

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
Blood‐feeding success (washed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 0.91 [0.74, 1.13]NRLow
Intervention NR
Mosquito mortality (unwashed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.25 [0.99, 1.57]NRModerate
Intervention NR
Mosquito mortality (washed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.39 [0.95, 2.04]NRVery low
Intervention NR
Blood‐feeding success (unwashed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 0.75 [0.27, 2.11]NRVery low
Intervention NR
Blood‐feeding success (washed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.07 [0.49, 2.33]NRLow
Intervention NR
Mosquito mortality (unwashed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.2 [0.64, 2.26]NRLow
Intervention NR
Mosquito mortality (washed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.07 [0.92, 1.25]NRLow
Intervention NR
Blood‐feeding success (unwashed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 0.52 [0.12, 2.22]NRVery low
Intervention NR
Parasite prevalence (9‐ to 12‐month · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
OR 0.72 [0.61, 0.86]2 studies · 11370 participantsModerate
Intervention NR
Blood‐feeding success (washed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.25 [0.82, 1.91]NRVery low
Intervention NR
Parasite prevalence (16‐ to 18‐month · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
OR 0.88 [0.74, 1.04]2 studies · 11822 participantsModerate
Intervention NR
Parasite prevalence (21‐ to 25‐month · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
OR 0.79 [0.67, 0.95]2 studies · 10603 participantsModerate
Intervention NR
Mosquito mortality (unwashed nets) · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.84 [1.6, 2.11]5 studies · 14620 participantsHigh
Intervention NR
Mosquito mortality (washed nets) · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.2 [0.88, 1.63]4 studies · 10268 participantsVery low
Intervention NR
Blood‐feeding success (unwashed nets) · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 0.6 [0.5, 0.71]4 studies · 14000 participantsHigh
Intervention NR
Blood‐feeding success (washed nets) · adults and childen living in malaria‐endemic areas, Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 0.81 [0.72, 0.92]3 studies · 9674 participantsHigh
Intervention NR
Mosquito mortality (unwashed nets) · Anopheles gambiae complex or Anopheles funestus group
Piperonyl butoxide (PBO) combined with pyrethroids in insecticide‐treated nets to prevent malaria in Africa (2021) · Cochrane
RR 1.68 [1.33, 2.11]NRModerate
Impact of Xpert MTB/RIF vs smear microscopy
All‐cause mortality among participants · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
RR 0.89 [0.75, 1.05]5 studies · 9932 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
All‐cause mortality at 6 months (subgroup) · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
RR 0.98 [0.78, 1.22]3 studies · 8143 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
All‐cause mortality in people who were HIV‐positive (subgroup) · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
OR 0.8 [0.67, 0.96]5 studies · 5855 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
Successful treatment outcome in participants treated for tuberculosis · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
OR 1.1 [0.95, 1.26]3 studies · 4802 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
Proportion of participants who were treated for tuberculosis · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
RR 1.1 [0.98, 1.23]5 studies · 8793 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
Pre‐treatment loss to · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
RR 0.59 [0.41, 0.85]3 studies · 1217 participantsModerate
Impact of Xpert MTB/RIF vs smear microscopy
Treated participants with bacteriological confirmation of tuberculosis · people being investigated for tuberculosis (TB)
Impact of the diagnostic test Xpert MTB/RIF on patient outcomes for tuberculosis (2021) · Cochrane
RR 1.44 [1.29, 1.61]6 studies · 2068 participantsModerate
Ivermectin vs control
Incidence of clinical malaria · adults and children living in malaria‐endemic areas
Ivermectin treatment in humans for reducing malaria transmission (2021) · Cochrane
no estimate extracted590 participantsVery low
Ivermectin vs control
Adverse events · adults and children living in malaria‐endemic areas
Ivermectin treatment in humans for reducing malaria transmission (2021) · Cochrane
RR 1.63 [1, 2.67]2712 participantsVery low
Rapid susceptibility methods vs standard methods versus placebo
Mortality · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
RR 1.1 [0.82, 1.46]6 studies · 1638 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Mortality (subgroup genotypic) · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
RR 1.02 [0.69, 1.49]4 studies · 1074 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Mortality (subgroup phenotypic) · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
RR 1.37 [0.8, 2.35]2 studies · 564 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Mortality (with stewardship) · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
RR 1.17 [0.81, 1.7]4 studies · 1404 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Mortality (without stewardship) · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
RR 0.89 [0.35, 2.27]2 studies · 234 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Time‐to‐discharge from hospital (days) · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
no estimate extracted4 studies · 1165 participantsLow
Rapid susceptibility methods vs standard methods versus placebo
Time‐to‐appropriate antibiotic · people with bloodstream infections
Rapid versus standard antimicrobial susceptibility testing to guide treatment of bloodstream infection (2021) · Cochrane
no estimate extracted5 studies · 1493 participantsLow
Hydroxychloroquine (HCQ) vs standard care or placebo
Death due to any cause · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 1.09 [0.99, 1.19]9 studies · 8208 participantsHigh
Hydroxychloroquine (HCQ) vs placebo
Participants with any adverse events · people who have been exposed to SARS‐CoV‐2
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 2.39 [1.83, 3.11]1 study · 700 participantsModerate
Hydroxychloroquine (HCQ) vs placebo
Participants with serious adverse events · people who have been exposed to SARS‐CoV‐2
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
no estimate extracted1 study · 700 participantsLow
Hydroxychloroquine (HCQ) vs standard care or placebo
Negative PCR for SARS‐CoV‐2 on respiratory samples at day 14 from enrolmentd · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 1 [0.91, 1.1]3 studies · 213 participantsLow
Hydroxychloroquine (HCQ) vs standard care or placebo
Progression to mechanical ventilation · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 1.11 [0.91, 1.37]3 studies · 4521 participantsModerate
Hydroxychloroquine (HCQ) vs standard care or placebo
Time to clinical improvement · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
HR 1.01 [0.59, 1.74]1 study · 119 participantsVery low
Hydroxychloroquine (HCQ) vs standard care or placebo
Participants with any adverse events · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 2.9 [1.49, 5.64]6 studies · 1394 participantsModerate
Hydroxychloroquine (HCQ) vs standard care or placebo
Participants with serious adverse events · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 0.82 [0.37, 1.79]6 studies · 1004 participantsLow
Hydroxychloroquine (HCQ) vs standard care or placebo
Participants with prolongation of QT‐interval on ECG · adults with mild to severe COVID‐19
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 8.47 [1.14, 63.03]1 study · 147 participantsVery low
Hydroxychloroquine (HCQ) vs placebo
Development of confirmed COVID‐19 at 14 days from enrolment · people who have been exposed to SARS‐CoV‐2
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 1.2 [0.5, 2.87]1 study · 821 participantsVery low
Hydroxychloroquine (HCQ) vs placebo
Hospitalized due to COVID‐19c · people who have been exposed to SARS‐CoV‐2
Chloroquine or hydroxychloroquine for prevention and treatment of COVID‐19 (2021) · Cochrane
RR 0.98 [0.06, 15.66]1 study · 821 participantsVery low
Intervention NR
Index test · children with close tuberculosis contacts Index tests: groups of multiple symptoms Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Specificities 99% and 100% · children evaluated in inpatient or outpatient settings Index tests: Xpert MTB/RIF Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extracted2 studies · 771 participantsModerate
Intervention NR
≥ 1 of cough, fever, or poor weight gain · children with close tuberculosis contacts Index tests: groups of multiple symptoms Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extracted4 studies · 113 participantsLow
Intervention NR
≥ 1 of cough, fever, or decreased playfulness · children with close tuberculosis contacts Index tests: groups of multiple symptoms Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extracted3 studies · 106 participantsModerate
Intervention NR
≥ 1 of cough, fever, poor weight gain, or tuberculosis close contact (WHO 4‐symptom symptom screen) · children with close tuberculosis contacts Index tests: groups of multiple symptoms Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extracted2 studies · 1219 participantsModerate
Intervention NR
Estimation (95% Cl) · children with close tuberculosis contacts Index test: abnormal chest radiography Role: an initial test Threshold for…
Screening tests for active pulmonary tuberculosis in children (2021) · Cochrane
no estimate extractedNRNo studies