sentence: In addition , because the exhaled nitric oxide test , which is used to assess lung inflammation and steroid effectiveness , is covered by insurance for patients under the DPC code name for bronchial asthma in Japan , it is possible that patients with asthma-like features who underwent this test were excluded from the dataset.In the DYNAGITO trial , where patients were selected for inclusion based on their COPD exacerbation history , the difference between tiotropium / olodaterol and tiotropium for the prevention of COPD exacerbations was not statistically significant [ 11 ] .