Subgroup analysis Subgroup analysis refers to repeating the analysis of a study within subgroups of subjects defined by a subgrouping variable. For example: smoking status defining two subgroups: smokers and non-smokers).[1] See alsoPost hoc analysisReferences ^ Lagakos SW (20 April 2006). "The Challenge of Subgroup Analyses — Reporting without Distorting". NEJM. 354 (16): 1667–9. doi:10.1056/NEJMp068070. PMID 16625007. S2CID 567177.