This study examined the utility of the K-correction procedure to adjust for
a defensive response set on the MMPI. The sample consisted of 61 patients
with end-stage lung disease undergoing psychosocial evaluation for transpla
ntation. Participants were separated into "defensive" and "non-defensive" g
roups using a median split on the K scale (defensive group T score greater
than or equal to 59) as the cutoff score. The, MMPI was scored once in the
standard manner and then rescored omitting all K-scale items from the clini
cal scales. As hypothesized, raw score analysis after omitting K-scale item
s showed the defensive group endorsed significantly fewer items on all five
scales involving K-correction (Scales Hs, Pd, Pt, Sc, Ma). Analysis of K-c
orrected T scores on Scales Hs, Pd, Pt, and Sc using standard procedures sh
owed a significant group difference only on Scale Hs with a higher T score
found among the defensive group. The defensive and nondefensive groups were
not significantly different in demographic, medical, or psychiatric charac
teristics suggesting that the tendency to respond in a defensive manner is
the major characteristic that distinguishes the two groups. Taken together,
these results provide support for the use of the K-correction procedure wh
en examining MMPI clinical profiles among patients with end-stage pulmonary
disease undergoing evaluation for transplantation.