Transcripts
MS. ORRBINE:
Cases and controls were very
carefully matched based on the basis of -- that
doesn't sound right -- age plus or minus one
year, time since illness within six months,
gender, first language and socioeconomic status.
Matching on SES was accomplished
using postal code data to select subjects living
in census tracts with mean annual incomes within
$10,000. Our study, of course, was approved by
all of the ethics committees at the six
participating centers.
