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In an effort to determine whether cues related to changes in energy contribute to the detection of a tone added to a narrow band of noise, we examined the effect of level variation on detection thresholds. In the first experiment, the level of each waveform was randomly varied on each presentation. Level variation had only marginal effects on performance. In addition, detection thresholds were obtained using bands of noise with equal energy across intervals. Neither increasing nor decreasing the variance of the noise-alone and tone-plus-noise energy difference distributions altered the detectability of a tone added to noise. Thus, the changes in energy that are concomitant with the addition of the tone are not the sole cue for the detection of the tone. In a second experiment, three psychometric functions were measured. One function was determined using no level variation, one was measured in the presence of level variation, and one was measured in the context of level variation, but for trials without level variation. The context of level variation slightly reduced detectability. In a third experiment, we compared detectability in three conditions: no level variation, across-trial level variation, and across-interval level variation. The thresholds obtained in the absence of level variation were superior to those measured in the presence of level variation, regardless of the manner in which the level variation was incorporated.  相似文献   
773.
Food, Mood, and Attitude (FMA) is a CD-ROM prevention program developed to decrease risk for eating disorders in college women. Female 1st-year students (N = 240) were randomly assigned to the intervention (FMA) or control group. Equal numbers of students at risk and of low risk for developing an eating disorder were assigned to each condition. Participants in the FMA condition improved on all measures relative to controls. Significant 3-way interactions (Time x Condition x Risk Status) were found on measures of internalization of sociocultural attitudes about thinness, shape concerns, and weight concerns, indicating that at-risk participants in the intervention group improved to a greater extent than did low-risk participants. At follow-up, significantly fewer women in the FMA group reported overeating and excessive exercise relative to controls.  相似文献   
774.
A semistructured interview was used to collect information on a consecutive series of 163 self-harm patients (suicide attempters); 65.8% of the patients had a history of previous self-harm (repeaters). Male repeaters were more likely than men with no self-harm history (first cases) to have left school before ninth grade, to have alcohol abuse problems, and to have family stress. Female repeaters were younger than first cases and reported more difficulties with sexual adjustment and loneliness. Repeaters were more likely to have contacted distress centers and to have had previous mental health contact, including psychiatric hospitalization. A 6-month follow-up indicated four suicides in the repeaters' group and none in the first cases' group. Repeaters appear to be much more dependent than first cases on professional care and to present a high short-term risk for suicide.  相似文献   
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Using a sample of Caucasian and Asian American college students, this research examined gender differences within race and race differences within gender with respect to a wide range of body image and disordered eating variables. Results indicated that: (a) regardless of race, women reported more problem attitudes and behaviors than did men; (b) gender differences were similar for Asian Americans and Caucasians, although Caucasians evidenced slightly more gender differences than did Asian Americans; (c) for men, race made no difference; and (d) for women, some race differences were found, with Caucasian women engaging in more dieting and binging behavior and Asian American women reporting lower self-esteem and less satisfaction with their racially defined features. Suggestions for future research are made, and implications are discussed.  相似文献   
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Joint Commission National Patient Safety Goal 15 calls for organizations “to identify patients at risk for suicide.” Overt suicidal behavior accounts for 0.6% of emergency department (ED) visits, but incidental suicidal ideation is found in 3%–11.6%. This is the first multicenter study of suicide screening in EDs. Of 2,243 patients in six diverse emergency settings, 1,068 (47.7%) were screened with a brief instrument. Depression was endorsed by 369 (34.5%); passive suicidal ideation by 79 (7.3%); and active suicidal ideation by 24 (2.3%). One hundred thirty‐seven (12.8%) reported prior attempts, including 35 (3.3%) with current suicidal ideation. Almost half of those with current ideation had a prior attempt (43.8%) versus those without current ideation, 10.3%, χ2 (1) = 75.59, < .001. Twenty cases (25%) were admitted to medical services, but only 10 (12.5%) received mental health assessment; none were admitted directly to a psychiatry service. The prevalence of suicidal ideation here is similar to previous studies but the frequency of prior attempts has not been reported. The 35 cases with current ideation and prior attempt are at risk. As they did not present psychiatrically, they would likely have gone undetected. Despite reporting these cases to clinical staff, few received risk assessment.  相似文献   
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Suicide research remains fraught with ethical and methodological issues, including researchers’ reservations about conducting intensive suicide research protocols due to potential iatrogenic effects and liability concerns. Such issues significantly impede scientific inquiry related to suicide. To date, no research has explored potential iatrogenic effects of intensive, nontreatment suicide research among Veterans. This study aimed to fill this gap. It was hypothesized that participation in suicide‐specific protocols would not significantly increase risk among Veterans. Veterans completed self‐reports, structured interviews, and rigorous suicide‐specific tasks (Study A, = 34; Study B, = 18; Study C, = 119). Findings indicated there were no significant differences in pre‐ and postassessment suicide risk variables (all ps > .05). Estimated mean change for “urge to harm self” was ?0.24 (95% confidence interval [CI]: ?0.60, 0.13), ?0.28 (CI: ?0.56, 0.01), and ?0.01 (CI: ?0.09, 0.07) and “intent to harm self” was ?0.18 (95% CI: ?0.45, 0.10), 0 (CI: ?0.17, 0.17), and 0.01 (CI: ?0.04, 0.06) for Studies A, B, and C, respectively. Results indicated the respective protocols did not produce iatrogenic effects. The current findings are discussed with attention to safety‐monitoring techniques that may reduce iatrogenic effects and considerations for future researchers.  相似文献   
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