This work is part of an effort to detect secular variable objects in large scale surveys by analysing their path in color-magnitude diagrams. To this aim, we first present the variability morphologies in the V/V-I diagram of several types of variable stars. They comprise both periodic and non periodic variable stars from the Large Magellanic Cloud, such as classical Cepheids, long period variables or Be and R Coronae Borealis stars, as well as two of the detected secular variable stars in the Galaxy, FG Sge and V4334 Sgr. The study of the different variability morphologies allows the identification of regions in the color-magnitude diagram where those secular variable stars could be detected. We also estimate the number of such secular variable stars expected in the Large Magellanic Cloud.

To appear in the proceedings of the conference on Stellar Pulsation: Challenges for theory and observations, Santa Fe, NM, 31 may-5 june 2009