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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.
2,325 questions in 216 reviews · Airways
current versionsNo studies 249 · 10.7%Ungraded 107 · 4.6%Very low 276 · 11.9%Low 751 · 32.3%Moderate 718 · 30.9%High 224 · 9.6%
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 |
|---|---|---|---|
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA Six‐minute walk distance · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 36 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA Mortality · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 3.19 [0.74, 13.64] | 2 studies · 272 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA Quality of life Kansas City Cardiomyopathy Quality‐of‐Life questionnaire (higher scores indicate better quality of life) · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 25 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo Six‐minute walk distance · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 8 studies · 880 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA PAP · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 11 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA RAP · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 11 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA Cardiac index · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 11 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs ERA PVR · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 11 participants | Low |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Improvement in WHO functional class · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 0.53 [0.32, 0.87] | 3 studies · 285 participants | Moderate |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Six‐minute walk distance · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 3 studies · 284 participants | Moderate |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Mortality · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 1.27 [0.28, 5.8] | 3 studies · 286 participants | Moderate |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Quality of life · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 52 participants | Low |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Mean PAP · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 3 studies · 130 participants | Moderate |
Group 2 Pulmonary hypertension due to left‐heart disease ‐ PDE5i vs placebo Cardiac index · people with pulmonary hypertension due to left‐heart disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 96 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo Mortality · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 0.22 [0.07, 0.68] | 8 studies · 1119 participants | High |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Improvement in WHO functional class · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 44.33 [4.78, 410.94] | 1 study · 40 participants | Low |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Six‐minute walk distance · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 5 studies · 350 participants | High |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Mortality · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | NR | No studies |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Quality of life · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 238 participants | Moderate |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Mean PAP · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 61 participants | Moderate |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo Cardiac index · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 28 participants | Low |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo PVR · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 28 participants | Low |
Group 3 Pulmonary hypertension due to lung disease ‐ PDE5i vs placebo RAP · people with pulmonary hypertension due to lung disease Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 28 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Improvement in WHO functional class · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 17.18 [0.78, 380.84] | 1 study · 19 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Six‐minute walk distance ‐ sildenafil compared to placebo · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 19 participants | Low |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo Quality of life SF‐36: (scores 1 to 100, higher scores indicate better QoL) EQ‐5D questionnaire: (higher scores indicate worse QoL) CHFQ: (lower scores indicate worse QoL) · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 163 participants | Ungraded |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Six‐minute walk distance ‐ sildenafil compared to bosentan · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 227 participants | Moderate |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Mortality ‐ sildenafil versus placebo · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 20 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Mortality ‐ sildenafil versus bosentan · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 1.36 [0.22, 8.48] | 1 study · 106 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Quality of life · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 34 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Mean PAP ‐ sildenafil versus placebo · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 19 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Mean PAP ‐ sildenafil versus bosentan · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 227 participants | Moderate |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Cardiac index ‐ sildenafil versus placebo · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 19 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo Cardiac index ‐ sildenafil versus bosentan · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 227 participants | Moderate |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo PVR ‐ sildenafil versus placebo · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 19 participants | Low |
Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placebo PVR ‐ sildenafil versus bosentan · people with pulmonary hypertension due to CTEPH Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 227 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo PAP · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 6 studies · 453 participants | Moderate |
Mixed Pulmonary hypertension group 2 ‐ 4 ‐ PDE5i vs placebo Improvement in WHO functional class · people with pulmonary hypertension group 2 ‐ 4 Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 11.31 [4.9, 26.14] | 2 studies · 146 participants | Moderate |
Mixed Pulmonary hypertension group 2 ‐ 4 ‐ PDE5i vs placebo Six‐minute walk distance · people with pulmonary hypertension group 2 ‐ 4 Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 1 study · 106 participants | Moderate |
Mixed Pulmonary hypertension group 2 ‐ 4 ‐ PDE5i vs placebo Mortality · people with pulmonary hypertension group 2 ‐ 4 Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | NR | No studies |
Mixed Pulmonary hypertension group 2 ‐ 4 ‐ PDE5i vs placebo Quality of life · people with pulmonary hypertension group 2 ‐ 4 Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | NR | No studies |
Mixed Pulmonary hypertension group 2 ‐ 4 ‐ PDE5i vs placebo PASP · people with pulmonary hypertension group 2 ‐ 4 Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 146 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo RAP · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 3 studies · 341 participants | High |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo Cardiac index · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 4 studies · 239 participants | Moderate |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo PVR · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | no estimate extracted | 3 studies · 266 participants | High |
Group 1 Pulmonary arterial hypertension ‐ PDE5i vs placebo, on combination therapy Improvement in WHO functional class · people with pulmonary arterial hypertension Phosphodiesterase 5 inhibitors for pulmonary hypertension (2019) · Cochrane | OR 1.2 [0.66, 2.17] | 2 studies · 227 participants | Moderate |
Prostacyclin vs control Improvement in WHO functional class · pulmonary arterial hypertension Prostacyclin for pulmonary arterial hypertension (2019) · Cochrane | OR 2.39 [1.72, 3.32] | 8 studies · 1066 participants | Moderate |
Prostacyclin vs control Headache+ · pulmonary arterial hypertension Prostacyclin for pulmonary arterial hypertension (2019) · Cochrane | no estimate extracted | 12 studies · 2351 participants | Moderate |
Selexipag vs placebo Improvement in WHO functional class · pulmonary arterial hypertension Prostacyclin for pulmonary arterial hypertension (2019) · Cochrane | OR 1.61 [0.17, 15.63] | 1 study · 43 participants | Moderate |
Selexipag vs placebo 6MWD · pulmonary arterial hypertension Prostacyclin for pulmonary arterial hypertension (2019) · Cochrane | no estimate extracted | 2 studies · 1199 participants | High |