The second technique involves finding any yet unmentioned elements from the resource examine.com for COPD. Lastly, we perform a search in clinicaltrails.gov with outcome measure “FEV1” OR “FVC” OR “FEV1/FVC”. The unique interventions are extracted. For each unique element, we perform a literature search for meta-analyses evaluating that particular intervention for its effect on the outcome measures FEV1, FVC or FEV1/FVC.
The third technique is finding the interventions on the examine.com page for COPD and recording these studies.