Types of interventions
Inclusion:
The intervention for the actively-treated group was oxygen therapy,
provided through wall oxygen units (in a hospital or clinic),portable oxygen cylinders or liquid oxygen canisters. Intervention
for the control group was either placebo (compressed air provided
by a wall unit or cylinders) or no intervention (room air). All interventions
were given during exercise training which was greater
than or equal to three weeks in duration and included a minimum
of two sessions a week. Formal (in hospital or a clinic) exercise
training as a part of rehabilitation was accepted.
Exclusion:
Long-term (at home for activities of daily living) or short-term
(single assessment) studies assessing the efficacy of ambulatory
oxygen therapy and studies assessing the efficacy of LTOT without
training or rehabilitation were excluded.