3.7.2. Show a Table of Twin Pair Status
Each interview ends with a status code called
event. The query shown here is used to
display a table over all twin pairs combined by event. This
indicates in how many pairs both twins are finished, in how many
pairs one twin is finished and the other refused, and so on.
lentus AS t1,
lentus AS t2,
twin_project AS tp
/* We are looking at one pair at a time */
t1.id = tp.id
AND t1.id = t2.id
/* Just the screening survey */
AND tp.survey_no = 5
/* This makes each pair only appear once */
AND t1.tvab='1' AND t2.tvab='2'