***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Thirty one studies (contributing 33 data sets), randomising 534 participants met the inclusion criteria of the review. Oxygen improved all pooled outcomes relating to endurance exercise capacity (distance, time, number of steps) and maximal exercise capacity (exercise time and work rate). Data relating to VO2 max could not be pooled and results from the original studies were not consistent. For the secondary outcomes of breathlessness, SaO2 and VE, comparisons were made at isotime. In all studies except two the isotime is defined as the time at which the placebo test ended. Oxygen improved breathlessness, SaO2/PaO2 and VE at isotime with endurance exercise testing. There was no data on breathlessness at isotime with maximal exercise testing. Oxygen improved SaO2/PaO2 and reduced VE at Isotime. This review provides some evidence from small, single assessment studies that ambulatory oxygen improves exercise performance in people with moderate to severe COPD. The results of the review may be affected by publication bias, and the small sample sizes in the studies. Although positive, the findings of the review require replication in larger trials with more distinct subgroups of participants. Maximal or endurance tests can be used in ambulatory oxygen assessment. Consideration should be given to the measurement of SaO2 and breathlessness at isotime as these provide important additional information. We recommend that these outcomes are included in the assessment for ambulatory oxygen. Future research needs to establish the level of benefit of ambulatory oxygen in specific subgroups of people with COPD.
Output:

Short-term studies indicate that people with chronic obstructive pulmonary disease respond to the administration of oxygen when they do exercise tests. Ambulatory oxygen is the use of supplemental oxygen during exercise and activities of daily living. One way to assess if ambulatory oxygen is beneficial for a patient with COPD is to compare the effects of breathing oxygen and breathing air on exercise capacity. Some people with COPD may benefit more than others, and trials should take account of whether people who do not already meet criteria for domiciliary oxygen also respond. This review shows that there is strong evidence that ambulatory oxygen (short-term) improves exercise capacity. Further research needs to focus on which COPD patients benefit from ambulatory oxygen, how much oxygen should be provided and the long-term effect of ambulatory oxygen.