Outcome: clinical complications
We found no statistically significant difference between the participants
receiving IS and those who had no respiratory treatment
in the meta-analysis of four studies (Celli 1984; Kulkarni 2010;
O’Connor 1988; Schwieger 1986).The relative risk (RR)was 0.59
(95% CI 0.30 to 1.18) for the incidence of clinical complications.