Sex-based differences in answering strategy and the influence of cross-sex hormones.

We investigated whether sex differences in answering strategy occur in normal controls (C). Furthermore, it was tested whether these sex differences were subject to change over time, and whether they were associated with hormonal treatment at time points 2 and 3 in patients with Gender Identity Disorder (GID). Two subtests measuring arithmetic ability were used: arithmetic aptitude (AA) and arithmetic operations (AO).