TY - JOUR T1 - LImitations of subgroup analyses in meta-analysis of cardiac resynchronization therapy by qrs duration—reply AU - Sipahi I Y1 - 2012/02/27 N1 - 10.1001/archinternmed.2011.1685 JO - Archives of Internal Medicine SP - 375 EP - 376 VL - 172 IS - 4 N2 - I disagree with the comments of Magee et al. There was no multiple testing in our meta-analysis. The approach used in this meta-analysis was different from the exploratory subgroup analyses of a single clinical trial. The predefined hypothesis of this meta-analysis was that patients with moderately prolonged QRS interval (ie, 120-150 milliseconds [ms]) do not benefit from cardiac resynchronization therapy (CRT), which was suggested by many investigators even before the major clinical trials of CRT were performed and is biologically plausible.1- 3 Therefore, the only subgroups examined in this analysis were moderately prolonged QRS interval vs severely prolonged QRS interval (ie, >150 ms). Because of this, making corrections for multiple testing does not pertain to this analysis. Moreover, even for a hypothetical situation where multiple testing would be relevant, the significant P value of <.001 for the difference in the response of the 2 QRS subgroups is so robust that the results would not change with any type of correction. SN - 0003-9926 M3 - doi: 10.1001/archinternmed.2011.1685 UR - http://dx.doi.org/10.1001/archinternmed.2011.1685 ER -