Ordered-subset analyses for schizophrenia by age at onset, CPT, or WCST (only results with a significant change in LOD scores are shown here).

aFamilies were randomly permuted for 1000 times with respect to the covariate ranking and a chromosome-wide p value for each chromosome was yielded.bSignificance level derived from simulations; a genome-wide empirical P-value cThe number of total families varied due to missing information on the covariate; subsets consisting of ≥ 15% of total families were reported here.*PP