Heterogeneity analysis
For the ADRB2 Arg16Gly polymorphism, the heterogeneity remained
high in the dominant, recessive, allele and homozygous models. To
further identify the sources of heterogeneity, Galbraith plots were
generated in four genetic models. Galbraith plot analysis identified one
outlier [18] that was outside the CI in the
dominant model, and two [13, 18] in the recessive,
allele and homozygous models which might contribute to the high
heterogeneity (Figure 4). After removing these outliers, the
heterogeneity was significantly reduced. However, the relationship
between Arg16Gly polymorphism and salbutamol responsiveness in these
genetic models was still non-significant: dominant model (OR=1.166, 95%
CI: 0.850-1.601, P =0.341, I2=49.7%,P H=0.063); recessive model (OR=0.887, 95% CI:
0.632-1.246, P =0.490, I2=0.00%,P H=0.631); allele model (OR=1.062, 95% CI:
0.858-1.314, P =0.580, I2=32.0%,P H=0.196) and additive model (OR=1.089, 95% CI:
0.736-1.612, P =0.671, I2=42.3%,P H=0.123).