My hypothesis was that social engagement would be associated with cognition. I set up a one-way MANOVA in SPSS to look at the association between social engagement (IV, 9 levels) and performance on 6 different cognitive tests. Because the IV had so many levels, I also set up a series of planned contrasts (equivalent to Helmert contrasts) so that I could see where the real difference lay. The overall ANOVAs came back as non-significant for all DVs bar one. However, for 3 of the tests, the same planned contrast came up as significant (p<0.01).
How could the planned contrasts come up as significant if the overall ANOVA was not? And how do I report this? Please help!