Sample
Witvliet et al. (2001) used 72 introductory psychology students (36 male, 36 female) and Lawler et al. (2003)
used 108 college students (44 male, 64 female) in their initial investigations providing construct validity data
regarding peripheral physiological measures as indexes for unforgiveness.
Reliability
Smith and Uchino (2008) highlighted that whereas physiological measures are touted as being more direct assess-
ments, the interpretation of peripheral physiological assessments is not unambiguous. Sources of error variance in
physiological measurements include sociodemographic characteristics, nutrition, health behaviors (e.g., smoking,
alcohol consumption). Also, artifacts may occur during data collection due to equipment or software error, electrode
placement, or human movement, posture, and speech. Measurement guidelines for calculations of HRV are pro-
vided by the Task Force (1996) .Gerin, Goyal, Mostofsky, and Shimbo (2008) enumerate problems of reliability in the
assessing blood pressure: blood pressure changes with heart beats and interbeat periods and blood pressure is
highly variable and is influenced by equipment, software, environmental, psychosocial, and physical condition fac-
tors. Reliable assessment of peripheral physiology requires attention to the possible sources of unwanted error vari-
ance, repeated assessments, and careful measurement techniques. Nevertheless, the reliability of peripheral
physiology assessments is easily estimated and quite high ( Smith & Uchino, 2008 ). In Witvliet’s general method of
investigating peripheral physiological measures, she uses a within subjects design; Lawler uses between subjects
designs. While Witvliet has reported no actual correlations on the estimated reliability of measurements, the use of
between subjects methods suggests that high test /C0retest reliability exists over the period of two to three minutes.
Validity
Organizations such as the Association for the Advancement of Medical Instrumentation have developed guide-
lines and standards for physiological assessment equipment (see also Fridlund & Cacioppo, 1986 ). Construct validity
of physiological assessments rests on correlations of averages with self-report instruments that indicate that forgive-
ness has occurred, including movement of a joystick to measure degree of forgiveness and associated emotions.
Witvliet et al. (2001) provided convergent construct validity in the form of an experiment using within-
subjects design. She instructed participants to reflect on a grudge and either (1) rehearse hurtful memories;
(2) nurse the grudge; (3) think empathically about why the offender might have inflicted the hurt; or (4) imagine
forgiving the offender. The two unforgiving imaginal tasks resulted in more diastolic and systolic blood pressure
(combined as mean arterial pressure), higher heart rate, higher skin conductance, and more muscular tension in
the corrugator (i.e., brow) relative to the empathy and forgiveness imagery conditions. These were related to self-
ratings of sadness, anger, and unforgiveness.
Location
Lawler, K.A., Younger, J.W., Piferi, R.L., Billington, E., Jobe, R., Edmondson, K., & Jones, W.H. (2003). A
change of heart: Cardiovascular correlates of forgiveness in response to interpersonal conflict. Journal of Behavioral
Medicine ,26, 373/C0393.
Witvliet, C.V.O., DeYoung, N.J., Hofelich, A.J., and DeYoung, P.A. (2011). Compassionate reappraisal and
emotion suppression as alternatives to offence-focused rumination: Implications for forgiveness and psychophysi-
ological well-being. Journal of Positive Psychology, 6 , 286/C0299.
Witvliet, C.V.O., Ludwig, T.E., & Vander Laan, K.L. (2001). Granting forgiveness or harboring grudges:
Implications for emotion, physiology, and health. Psychological Science, 121 , 117/C0123.
Note: Equipment for peripheral physiological assessment is available from sources such as Biopac, Coulbourn,
Finapres, Ohmeda, and Omron, and others.
Results and Comments
Each of the peripheral physiological assessments discussed above should be evaluated for their reliability and
validity independent of their use as measures of forgiveness. It is vital to consider in interdisciplinary frame-
works how these physiological measures are related to the ways that people embody forgiveness and unforgive-
ness responses. At present, it would be prudent to conclude that various measures of peripheral physiological
activity offer the potential to provide insight into how state-forgiveness and trait-forgivingness processes are
embodied and objectified. All software packages that come with equipment should be cross-checked carefully for
the accuracy of calculations, particularly for HRV (see Witvliet et al., 2010, 2011 , Methods and notes).489 STATES OF FORGIVENESS
IV. INTERPERSONAL STYLES