It is often difficult, particularly when conducting research in psychology, to have access to large normally distributed samples. Fortunately, there are statistical tests to compare two independent groups that do not require large normally distributed samples. The Mann-Whitney U is one of these tests. In the following work, a summary of this test is presented. The explanation of the logic underlying this test and its application are presented. Moreover, the forces and weaknesses of the Mann-Whitney U are mentioned. One major limit of the Mann-Whitney U is that the type I error or alpha (α) is amplified in a situation of heteroscedasticity.

Social support and coping are both related to posttraumatic stress disorder (PTSD) symptoms, but the mechanisms underlying their relationships remain unclear. This study explores these relationships by examining the perceived frequency of supportive and countersupportive interactions with a significant other in PTSD patients. Ninety-six participants with PTSD were recruited and completed questionnaires assessing social interactions, ways of coping, and PTSD symptoms. Associations of social interactions (r = 4.1%-7.9%, p < .05) and coping (r = 15.9%-16.5%, p < .001) with symptoms were independent, and suggested a direct association between social interactions and PTSD. Countersupportive interactions were more associated to symptoms than supportive interactions. Our findings suggest the development of psychotherapies that integrate social support interventions.

Although a wide array of the scientific literature explores the links between posttraumatic stress disorder (PTSD) symptoms, coping strategies, and social support and health-related quality of life (HRQoL) as an outcome variable, their connections remain unclear. It is unknown whether PTSD symptom severity, coping strategies, and social support explain each a unique portion of variance of HRQoL of individuals with PTSD. In the current study, based on pretreatment results of a broader study assessing a specific intervention for PTSD, 94 individuals with PTSD were screened for psychiatric disorders and completed several questionnaires concerning social support, coping strategies, PTSD symptoms, and HRQoL. Coping strategies, social support, and PTSD all appeared to be predictors of HRQoL; however, PTSD seemed to constitute the major predictor among these variables. Indeed, coping strategies and social support did not explain a unique share of variability of HRQoL beyond that of PTSD symptomatology. A causal pathway integrating these variables should be tested in future studies. Keywordsposttraumatic stress disorder; health-related quality of life; social support; coping strategies; correlational study; clinical sample Posttraumatic stress disorder (PTSD) is commonly conceptualized as a multidimensional construct with three clusters of symptoms: (1) intrusion or persistent reexperiencing of the traumatic event, (2) persistent avoidance of stimuli associated with the trauma and numbing of general responsiveness, and (3) hyperarousal or persistent symptoms of increased arousal (American Psychiatric Association [APA], 2000). Following exposure to an extremely traumatic event that involved feelings of intense fear, helplessness, or horror, individuals diagnosed with PTSD usually experience each of these responses intensely, which seemingly causes high functional impairment and a decreased quality of life (d

Women are twice as likely as men to develop a posttraumatic stress disorder (PTSD). Gender differences in social support after a traumatic event might partially explain this disparity. However, the portrait of the links among PTSD, depression, social support, and gender is still unclear. This study examined behaviors of individuals with PTSD and their significant other in relation to PTSD and concurrent depressive symptoms, and tested gender as a moderator of these associations. Observed overt supportive and countersupportive behaviors of 68 dyads composed of an individual with PTSD and a significant other in a trauma-oriented discussion were coded with a support coding system and analyzed according to gender. Gender was revealed to act as a moderator of the links between interactional behaviors of individuals with PTSD and their concurrent depressive symptoms. More specifically, women were less implicated and less likely to propose positive solutions compared with men. On the other hand, men were more implicated and less likely to criticize their significant other than were women. PTSD and concurrent depressive symptoms were related to poorer interpersonal communication in women. Hence, women and men with PTSD and concurrent depressive symptoms might benefit from gender-tailored interventions targeting symptoms and dyadic behaviors.

Individuals with posttraumatic stress disorder (PTSD) commonly make efforts to avoid trauma-oriented conversations with their significant others, which may interfere with the natural recovery process. Trauma-oriented conversations can be experienced as physiologically arousing, depending on the intensity of PTSD symptoms and perceptions of social support. In the current investigation, changes in heart rate responses to a trauma-oriented social interaction with a significant other were assessed. Perceived supportive and unsupportive or negative social interactions were examined as moderators of the association between heart rate changes to this context and intensity of PTSD symptoms. A total of 46 individuals with PTSD completed diagnostic interviews and self-report measures of symptoms and perceived supportive and negative social interactions during a trauma-oriented social interaction with a significant other. Heart rate was continuously measured during this interaction. Results showed that engagement in a trauma-oriented social interaction was predictive of elevations in heart rate that positively correlated with intensity of PTSD symptoms. The moderation hypothesis was partially supported. In addition, perceived negative social interactions positively correlated with elevations in heart rate. These findings can inform social intervention efforts for individuals with PTSD.