Table 3—

Standardised mean difference from a single outcome

First author [ref no.]	Endpoint	Effect size
First author [ref no.]	Endpoint	d	S_d
Chow 25	FEV₁	0.257	0.254
Fung 26	PEFR	0.522	0.245
Morton 28	FEV₁	0.130	0.279
Tashkin 30	FEV₁	0.225	0.292
Christensen 2	PEFR	0.210	0.487
Luu 27	PEFR	0.560	0.495
Dias 6	PEFR	−1.293	0.536
Tandon 24	PEFR	0.054	0.259
Tashkin 23	FEV₁	−0.138	0.201
Overall		0.120	0.096

FEV₁: forced expiratory volume in one second
PEFR: peak expiratory flow rate
d: standardised mean difference
S_d: standard error