Dear All,
This regards an outcome study. I would much appreciate any input.
Some young people completed only one type of form over 5 time points (i.e.
the ASEBA YSR, the adolescent equivalent), as they remained in the age
range specified for this form (similarly some completed only the YASR
across time). Nevertheless, in some cases the YSR was completed first
(e.g. at intake and 3 months), and the YASR (for young adults) was
completed at the remaining time points, reflecting the young person's
transition from one age group (adolescents) to another (young adults).
I recently asked Professor Achenbach to guide me as to how I could
standardise the scores to make valid comparisons, who replied:
Answer to your questions:
Because repeated administrations of a form might affect scores, I suggest
the following:
1. Separately for each gender, use the raw scale scores from the first
YSRs completed by participants as a basis for assigning standard scores
with a mean = 100, SD = 15 for each scale.
2. Do the same for all the first YASRs.
3. After you have used the first-completed forms to establish relations
between raw scale scores and standard scores, you can apply the standard
scores to the raw scores of the later-completed forms, as well as to the
first-completed forms.
I know how to do steps 1 and 2 but I am not sure I understand step 3. How
do I establish relations between raw scale scores and standard scores, in
order to apply the standard scores to the raw scores of the
later-completed forms, as well as to the first-completed forms?
Is this obvious to anybody? If yes I would hugely appreciate a couple of
lines explaining what I should do.
Many thanks in advance
Ioanna
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