Fig. 1From: Efficacy of adjuvant chemotherapy stratified by age and the 21-gene recurrence score in estrogen receptor-positive breast cancerAdjustment for imbalances in baseline covariates by propensity score matching. The red squares represent the standard difference of propensity score between chemotherapy and no-chemotherapy groups before PSM. The blue squares represent the standard difference of propensity score between two groups after PSM. The standardized difference for all covariates met the criteria of < 20% after PSMBack to article page