Estimates from MR Egger regression for combination B (MR Egger regression was not applied to combination A as there were not enough SNPs) were in the same direction as estimates from the other two methods with a 0.81 (95% CI 0.60 to 1.09) OR for asthma per unit increase in log SHBG, but with wider CIs that spanned the null (online supplementary figure S4 appendix A1), possibly reflecting the lower statistical power of MR Egger regression. Here, SHBG is linked to asthma.