Construct validity of the posttraumatic stress disorder checklist in cancer survivors: analyses based on two samples

The measurement of posttraumatic stress disorder (PTSD) is critically important for the identification and treatment of this disorder. The PTSD Checklist (PCL; F. W. Weathers and J. Ford, 1996) is a self-report measure that is increasingly used. In this study, the authors investigated the factorial validity of the PCL with data from 236 cancer survivors who received a bone marrow or stem cell transplantation. The authors examined the fit of these data with the clinical model of 3 symptom clusters for PTSD, as proposed in the Diagnostic and Statistical Manual of Mental Disorders, and alternative models tested in prior research. By using confirmatory factor analysis the authors found that a 4-first-order-factor model of PTSD provided the best fit. The relations of PTSD symptoms with sociodemographic and medical variables were also explored.     

Ratio scales of acid sourness

Experiments were conducted to assess the relation between concentration, or pH, and the perceived sourness of 24 acids. The psychophysical functions for sourness conform to the power relation S = kCⁿ which relates sensory intensity, S, to physical concentration, C. Averaged across the 24 acids, the exponent for sourness was 0.85 for both molar and percentage concentrations, and about ?1.70 for pH concentration. The intercept, k, which is a measure of relative sourness, differed across acids. The particular measure used to designate the concentration of an acid markedly influenced its magnitude and rank order of sourness.     

Ratio scales of sugar sweetness

In a series of 10 experiments, groups of Os judged the sweetness of 16 sugars. The results suggest that, for all sugars except mannose, the intensity of sweetness grows as a power function of concentration, with an exponent of about 1.3. The relative sweetness of sugars was determined using both molarity and per cent by weight. With both measures, sucrose and fructose were the sweetest sugars. The order of the remaining sugars in the sweetness hierarchy was partiy a function of the measure of concentration. The variability of the magnitude estimates of sweetness was roughly proportional to the stimulus concentration, supporting Weber’s law.     

Sweetness and intensity of artificial sweeteners

In four experiments, groups of Os judged either the sweetness or the entire taste intensity of solutions of sucrose, cyclamate salts, cyclamate-saccharin mixtures, and sodium saccharin. The sensory functions obtained by magnitude estimation suggest that over the middle range of concentration the sweetness and intensity of the foregoing substances grow as power functions of concentration. As a first approximation, the exponents for sweetness and intensity are, respectively, 1.6 to 1.4 for sucrose, 1.0 to 0.8 for cyclamate salts, 0.6 to 0.85 for cyclamate-saccharin mixtures, and 0.3 to 0.6 for sodium saccharin.     

Stress, Positive Emotion, and Coping

There is growing interest in positive aspects of the stress process, including positive outcomes of stress and antecedents that dispose individuals to appraise stressful situations more as a challenge than as a threat. Less attention has been given to the adaptational significance of positive emotions during stress or to the coping processes that sustain positive emotions. We review evidence for the occurrence of positive emotions under conditions of stress, discuss the functional role that positive emotions play under such conditions, and present three types of coping that are associated with positive emotion during chronic stress. These findings point to new research questions about the role of positive emotions during stress and the nature of the coping processes that generate these positive emotions.     

Stability and variability of affective experience and interpersonal behavior in borderline personality disorder

This study examined both mean levels and intraindividual variability in the mood and interpersonal behavior of individuals with borderline personality disorder (BPD) and nonclinical control participants over a 20-day event-contingent recording period. Individuals in the BPD group experienced more unpleasantly valenced affect and were less dominant, more submissive, more quarrelsome, and more extreme in overall levels of behavior than control participants. In addition to these mean-level differences, individuals with BPD also reported more intraindividual variability in overall affect valence and in pleasantly valenced affect; displayed greater variability in dominant, quarrelsome, and agreeable behaviors; and exhibited an increased tendency to "spin" among interpersonal behaviors relative to nonclinical control participants. The findings document behavioral and affective manifestations of BPD in the context of naturally occurring interpersonal situations.