The six year-old version of the adaptive PPVT-III for use in LSAY was developed so that it
can be linked with the four year-old version of the test. This allows the measurement of
growth between administrations of the test. Forty items were selected for the test, with 20
items administered to all children as the core set (core sets 1 and 2). For children who
make 15 to 20 errors an additional basal set of 10 items is administered, and for children
who make 0 to 6 errors an additional ceiling set of 10 items is administered. Simulations
showed that approximately two-thirds (67%) of children would require only the core sets, 7
per cent would require the core and basal sets, and 26 per cent would require the core and
ceiling sets; this distribution was considered in the selection of items.