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The Cochrane Review Group are withdrawing this protocol because the authors were not able to continue with the review.
Blakey, J., Hodgson, D., & Bolton, C. E. (2017). Inspiratory muscle training for chronic obstructive pulmonary disease. Cochrane Database of Systematic Reviews, 2017(6). https://doi.org/10.1002/14651858.CD009428.pub2