feeling bitterness, resentment, unwillingness to forgive, and desire for revenge. High scores indicate a disposition
to forgive. Each item is rated on a 5-point Likert-type response scale from 1 5Strongly Disagree to
55Strongly Agree .
Berry and Worthington (2001) reported an initial study in which a 15-item scale assessing trait forgivingness
was correlated with other measures of forgivingness. In a pilot study to Berry et al. (2005) , the authors reduced
the length of the TFS, using Rasch modeling within item response theory (IRT), to its final version of ten items.
The TFS had good person separation reliability, item separation reliability, and mean square weighted fit statis-
tics. The assumptions of IRT suggest that items are differentially harder to endorse along a scale measured in
logit units. The objective of IRT is to scale items from easy to endorse to hard to endorse in almost equal steps
with clearly defined items (i.e., each item has a small standard error of measurement). Item characteristic curves
are then fit to an ideal IRT model. Once this is done, it is assumed that all items measure the same latent con-
struct (though not equally well, as assumed by classical measurement theory, CMT), and CMT can be used to
further support the estimated internal consistency (albeit with somewhat lower alphas /C0if computed /C0than
when items are constructed under CMT alone) of the of scale scores, consistency of the factor structure (using
EFAs), and fit to the measurement model (using CFAs).
Sample
Berry et al. (2005) examined the psychometric properties of the TFS using four samples of 179, 233, 80, and 66
undergraduate students. The first two samples were from a Mid-Atlantic state university, the third from a private
university in the Pacific Northwest, and the fourth from a large state university in the San Francisco Bay area.
In the fourth study, partners of students also participated.
Reliability
Internal Consistency
Berry et al. (2005) reported all IRT and classical measurement statistics across four studies. Cronbach alpha
coefficients were found to range from .74 to .80 across the four studies.
Test/C0Retest
TFS scores were stable over eight weeks, r5.78. The correlations between item difficulty estimates across the
eight weeks was r5.98 (Berry et al., 2005 ).Berry, Worthington, Parrott, O’Connor, and Wade (2001) employed
four samples and analyzed the combined sample, adducing evidence in support of temporal stability of the TFS
(8 weeks, r5.69; correlations between item difficulty estimates across the eight weeks was r5.99), and construct
validity of the TFS against similar instruments with which the TFS was correlated.
Validity
Convergent/Concurrent
In two studies, Berry et al. (2005) reported positive correlations (.50 and .48) between scores on the TFS and
the Transgression Narrative Test of Forgivingness (TNTF; Berry et al., 2001 )/C0(the TNTF involves five scenarios
relevant for college students; IRT was employed in its construction). Across three studies, scores on the TFS
were positively correlated with the Big Five Inventory : agreeableness (mean r5.56), and conscientiousness (mean
r5.25), Interpersonal Reactivity Inventory : empathic concern (mean r5.30), and perspective taking (mean r5.29).
In romantic couples, self-ratings and partner ratings were positively correlated ( r5.35) ( Berry et al., 2005 ).
Divergent/Discriminant
Berry et al. (2005) reported that across three studies, scores on the TFS were negatively correlated with the
Trait Anger Scale (mean r52.47), Big Five Inventory : neuroticism (mean r52.38), Fear Questionnaire (mean
r52.36), Dissipation Rumination Scale ( 2.65), Aggression Questionnaire : anger ( 2.40), hostility ( 2.35), verbal
aggression ( 2.10), and physical aggression ( 2.17). Also, negligible correlations were found with the Big Five
Inventory: extraversion (.09), and openness (.08) ( Berry et al., 2005 ).
Construct/Factor Analytic
Berry et al. (2005) used item response theory to provide evidence for structural validity rather than exploratory
or confirmatory factor analytic methods.494 17. MEASURES OF FORGIVENESS
IV. INTERPERSONAL STYLES