Twenty-two studies with 542 patients were included.
There was no significant heterogeneity of the trial results for comparison of different CPT modalities (p>0.05).
Standard therapy versus no therapy (3 studies involving 66 patients). The overall effect size (ES) was 0.61 SD units (p<0.0001), indicating a significant benefit of standard CPT over no therapy for patients with CF; this corresponds to 7.5 g expectorated sputum per day.
PEP versus STD (8 studies). Six studies involving 146 patients evaluated FEV1. The pooled ES was 0.02 (95% CI: -0.32, 0.43, p=0.27), demonstrating equivalency of STD and the PEP mask. This equivalency was also shown in 6 studies with 100 patients: the pooled ES for sputum weight was 0.08 (95% CI: -0.39, 0.23, p=0.31).
EX and STD versus STD (53 patients). Three studies reported a pooled ES of 0.48 (95% CI: 0.07, 1.02, p=0.04), indicating a clinically-important and statistically-significant benefit of STD combined with EX to STD alone, which corresponds to a 6.4% predicted FEV1.
FET versus STD (5 studies involving 186 patients). The pooled ES was 0.13 demonstrating no difference between the 2 treatments (95% CI: -0.17, 0.43, p=0.19) on FEV1. For studies which evaluated sputum weight (involving 123 patients) the ES was 0.27 (95% CI: -0.65, 0.10, p=0.08), indicating a small but not statistically-significant trend favouring FET over STD alone in sputum expectoration.
Cough versus STD (2 studies involving 30 patients). Both trials showed a benefit of STD over cough alone. The pooled ES was 0.23 in favour of STD (95% CI: -0.49, 0.95, p=0.27). There appears to be a small but non significant trend favouring STD over cough alone with respect to sputum production.
AD verus STD (1 study involving 28 patients). AD demonstrated equivalence to STD and PEP mask in the outcome of FEV1, but was superior to others in the amount of sputum expectorated.
Mechanical versus manual percussion/vibration (4 studies involving 68 patients). FEV1 demonstrated equivalency of manual and mechanical percussion/vibration with an ES of 0.04 SD units (95% CI: -0.54, 0.47, p=0.48). The pooled ES for the outcome of sputum weight of 0.12 (95% CI: -0.35, 0.58, p=0.31) also demonstrated equivalency of the two methods.