Table 1 Frequency of overall error with devices (quantitative and qualitative estimates)

From: Device errors in asthma and COPD: systematic literature review and meta-analysis

Device

Cross-sectional studies

RCTs

 

Number of studies

Pooled estimate [95% CI] (I-squared)*

Range of error frequency

Number of studies

Pooled estimate [95% CI] (I-squared)*

Range of error frequency

MDI

19

86.8% [79.4–91.95] (98.5%)

45.7–100.0%

2

89.5% [75.7–95.9] (60.0%)

85.1–94.2%

MDI with spacer

3

52.0% [24.3–78.6] (87.3%)

31.6–78.0%

0

N/A

N/A

BA-MDI (Autohaler®)

2

57.7% [52.9–62.5] (84.9%)

54.9–59.9%

0

N/A

N/A

Turbuhaler®

4

55.5% [24.5–82.7] (93.6%)

22.0–88.7%

3

73.6% [55.6–86.1] (92.1%)

54.0–82.2%

Diskus®

1

N/A

49.0%

3

62.4% [51.9–72.0] (61.6%)

50.0–68.3%

Aerolizer®

2

75.1% [31.0–95.3] (97.2%)

54.0–89.1%

0

N/A

N/A

Handihaler®

0

N/A

N/A

1

N/A

66.7%

  1. N/A Not applicable
  2. * I-squared statistic indicates the percentage of variance that is attributable to between-study heterogeneity. The higher the percentage, the greater the heterogeneity. Not applicable as number of studies was ≤1