In medical studies, the efficacy of medical treatments (called interventions) is evaluated within a group of study participants. You will be given a sentence of a study report in which your task is to list the phrases that describe the intervention(s) of the study. You should list the phrase in the same order that they appear in the text, separated by commas. If no information about the interventions is mentioned, just answer with "not found". Interventions are: a specific drug, surgery, talking therapy, a lifestyle modification, control or placebo treatment. Do not include details, dosages, frequency and duration, intervention mentions that are not in an informative span of text.

[EX Q]: However , there was an inverse relation between time-varying abstinence ( vs. smoking ) and concurrent level of depressive symptoms , indicating that transitions from smoking to abstinence within individuals were associated with reductions in depressive symptoms .
[EX A]: not found

[EX Q]: However , to our knowledge , there have been no studies using all these measures together as an adjuvant antidepressant strategy .
[EX A]: not found

[EX Q]: Assessment of acute bronchodilator effects from specific airway resistance changes in stable COPD patients .
[EX A]:
bronchodilator