Notes on data release (n=785):
The current data release contains all subjects who gave an
unambiguous response to questions concerning ethnic background,
with the following filtering to obtain a clean dataset for
analysis. In the case of subjects with Asian Ethnicity, we
only included those subjects whose specific Asian background
was listed as either Korean, Japanese or Chinese. Subjects
where ethnicity and Asian background conflicted were removed
(n=2). Only white subjects with childhoods in North America
are included. Chinese, Japanese and Korean subjects with
childhoods in either North America (USA and Canada) or Asia
are provided, and where childhood was listed as both
(n=1; Japan/USA), we considered that individual to have had
substantial Asian childhood exposure. Finally, only subjects
who clearly answered YES or NO to the presence of AP are
included. Subjects with ambiguous responses concerning the
presence of AP (n=225) were not included in our analysis.
Information on age beginning formal music training was not
available on 6 subjects.
(September 2006)