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Vizzeri et al. (1696) evaluated the agreement of glaucoma progression by Heidelberg retinal tomograph (HRT), topographic change analysis (TCA), optic disc stereophotographs assessment, and standard automated perimetry guided progression analysis (GPA), and investigated potential factors accountable for agreement/non-agreement. As had been earlier observed, there was minimal concordance between different methods of progression analysis. A significantly greater proportion of eyes were detected as progressing by TCA (18%-40%) than by stereophotographs assessment (7%) and visual field GPA (9%) even when the specificity cutoff of TCA was set to 99%. In general, eyes with progression detected by more than one method had a more advanced disease (a smaller MD, a greater PSD and a larger cup/disc ratio) at baseline than those detected by TCA only. The performance of progression analysis is dictated by the methods of analysis, variability of instruments, choice of parameters, severity of disease and pattern of progression. Multiple approaches are often needed to optimize the performance of progression detection. Vizzeri et al. demonstrated that digital imaging could provide complementary information and augment detection of glaucoma progression. While it remains obscure how much change should be considered clinically meaningful, it is hopeful that we can reach a consensus in the near future when more data from long-term longitudinal studies become available.