Age-period-cohort analysis is mathematically intractable because of fundamental nonidentifiability of linear trends. However, some understanding can be gained in the context of individual problems.
Cite
@article{arxiv.0907.2480,
title = {Thoughts on new statistical procedures for age-period-cohort analyses},
author = {Andrew Gelman},
journal= {arXiv preprint arXiv:0907.2480},
year = {2009}
}