Clinical experience and pre-test probability scores in the diagnosis of pulmonary embolism.

BACKGROUND: The Geneva and Wells pre-test probability scores are intended to replace empirical assessment of patients with suspected pulmonary embolism (PE). The effect of clinical experience on the inter-rater variability of these scores, and on empirical judgement, is unknown. AIM: To determine whether medical staff appointment grade affects the inter-rater variability of these pre-test probability scores, or empirical assessment, in patients with suspected PE. DESIGN: Questionnaire survey. METHODS: Doctors were grouped by grade (mean number of years since graduation+/-SEM): house officers 0.7+/-0.2, registrars 6.3+/-0.6, consultants 25+/-4 and applied pre-test probability scores to actual case scenarios. RESULTS: The Geneva score was the most consistent method of determining pre-test probability and was unaffected by clinical experience (Geneva kappa=0.73, Wells kappa=0.38, empirical kappa=0.23, p<0.001 ). With empirical judgement, inter-rater variability was inversely proportional to clinical experience (house officers kappa=0.37, registrars kappa=0.24, consultants kappa= 0.16, p<0.05). DISCUSSION: The Geneva score was the least variable method and can be applied by junior or senior doctors. Using empirical judgement, junior doctors were more likely to agree on the pre-test probability of PE than were their more senior colleagues. This may imply that as physicians gain experience, they recognize that the diagnosis of PE can be difficult to assess and are reluctant to exclude it on clinical grounds.

An fMRI investigation of emotional engagement in moral judgment.

The long-standing rationalist tradition in moral psychology emphasizes the role of reason in moral judgment. A more recent trend places increased emphasis on emotion. Although both reason and emotion are likely to play important roles in moral judgment, relatively little is known about their neural correlates, the nature of their interaction, and the factors that modulate their respective behavioral influences in the context of moral judgment. In two functional magnetic resonance imaging (fMRI) studies using moral dilemmas as probes, we apply the methods of cognitive neuroscience to the study of moral judgment. We argue that moral dilemmas vary systematically in the extent to which they engage emotional processing and that these variations in emotional engagement influence moral judgment. These results may shed light on some puzzling patterns in moral judgment observed by contemporary philosophers.

Ambulatory estimates of maximal aerobic power from foot -ground contact times and heart rates in running humans.

Seeking to develop a simple ambulatory test of maximal aerobic power (VO(2 max)), we hypothesized that the ratio of inverse foot-ground contact time (1/t(c)) to heart rate (HR) during steady-speed running would accurately predict VO(2 max). Given the direct relationship between 1/t(c) and mass-specific O(2) uptake during running, the ratio 1/t(c). HR should reflect mass-specific O(2) pulse and, in turn, aerobic power. We divided 36 volunteers into matched experimental and validation groups. VO(2 max) was determined by a treadmill test to volitional fatigue. Ambulatory monitors on the shoe and chest recorded foot-ground contact time (t(c)) and steady-state HR, respectively, at a series of submaximal running speeds. In the experimental group, aerobic fitness index (1/t(c). HR) was nearly constant across running speed and correlated with VO(2 max) (r = 0.90). The regression equation derived from data from the experimental group predicted VO(2 max) from the 1/t(c). HR values in the validation group within 8.3% and 4.7 ml O(2) x kg(-1) x min(-1) (r = 0.84) of measured values. We conclude that simultaneous measurements of foot-ground constant times and heart rates during level running at a freely chosen constant speed can provide accurate estimates of maximal aerobic power.

Incapacitation and just deserts as motives for punishment.

What motivates a person's desire to punish actors who commit intentional, counternormative harms? Two possible answers are a just deserts motive or a desire to incarcerate the actor so that he cannot be a further danger to society. Research participants in two experiments assigned punishments to actors whose offenses were varied with respect to the moral seriousness of the offense and the likelihood that the perpetrator would commit similar future offenses. Respondents increased the punishment as the seriousness of the offense increased, but their sentences were not affected by variations in the likelihood of committing future offenses, suggesting that just deserts was the primary sentencing motive. Only in a case in which a brain tumor was identified as the cause of an actor's violent action, a case that does not fit the standard prototype of a crime intentionally committed, did respondents show a desire to incarcerate the actor in order to prevent future harms rather than assigning a just deserts based punishment.

Erythropoiesis and renal transplant pregnancy.

OBJECTIVE: To examine erythropoiesis in renal transplant pregnancies. METHODS: Retrospective cohort study of 30 renal transplant cases and 30 age, smoking and parity-matched healthy controls with normal index pregnancy. Retrospective chart review and assay of frozen antenatal serum (for serum erythropoietin concentration [serum EPO]), transferrin receptor protein [TfR], ferritin, folate and B12) were performed. The linear regression equation for normal pregnancy controls was used to calculate predicted [serum EPO] and the observed/predicted (O/P) log [serum EPO] was plotted. The relationship between [serum EPO] and haemoglobin (Hb) among transplant cases was considered to be different from that among controls if the slope of the O/P log [serum EPO] versus Hb regression was significantly different from zero. RESULTS: The transplant (14 cadaveric) to conception interval was (median [range]) 33.5 [4, 189] months. Immunosuppressants were azathioprine (n = 25), cyclosporine (n = 22) and/or prednisone (n = 25). Cases were more often primiparous (20 vs. 7 [controls]; p = 0.01), had pre-existent hypertension (20 vs. 0 [controls]; p < 0.001), developed new/increased hypertension or pre-eclampsia (28 vs. 0 [controls]; p < 0.001) and an antenatal rise in creatinine (14 vs. 2 [controls]; p < 0.001). In early pregnancy, cases had similar EPO (15.2 [2.6, 84.6] vs. 15.7 [6.4, 41.0] [controls] U/L) but lower Hb (101 [65, 129] vs. 116 [106, 150] g/L; p < 0.001). Twenty-two (73%) cases had Hb < 100 g/L (vs. 4 [controls]; p < 0.0001); Hb was comparable at 6 wk postpartum. With advancing gestational age (GA), Hb remained stable and serum EPO increased in both groups. The slope of the O/P log [serum EPO] versus Hb for transplant cases was significantly different from zero within both the 17-28 wk (slope +/- SEM: 0.010 +/- 0.002; p < 0.0001) and the 29-42 wk GA categories (0.006 +/- 0.003; p = 0.02). Cases showed smaller rises in serum TfR (change 481 [- 1471, 2780]) vs. 1119 [- 698, 4195] [controls] ng/mL; p = 0.005). CONCLUSIONS: Anaemia frequently complicates renal transplant pregnancies, in which serum EPO is inappropriately low and the rate of erythropoiesis blunted.

Genetic influences on F cells and other hematologic variables: a twin heritability study.

To assess the relative contribution of genetic factors in the variation of F cells (FC) and other hematologic variables, we conducted a classical twin study in unselected twins. The sample included 264 identical (monozygotic [MZ]) twin pairs and 511 nonidentical (dizygotic [DZ]) same-sex twin pairs (aged 20 to 80 years) from the St. Thomas' UK Adult Twin Register. The FC values were distributed continuously and positively skewed, with values ranging from 0.6% to 22%. FC values were higher in women than in men and decreased with age, with the variables accounting for 2% of the total FC variance. The intraclass correlations of FC values were higher in MZ (rMZ = 0.89) than in DZ (rDZ = 0.49) twins. The XmnI-(G)gamma polymorphism in the beta-globin gene cluster had a significant effect on FC levels, accounting for approximately 13% of the total FC variance. Variance components analysis showed that the FC values were accounted for predominantly by additive genetic and nonshared environmental influences, with an estimate of heritability of 0.89. Hemoglobin levels and red blood cell, white blood cell, and platelet numbers were also substantially heritable, with heritability estimates of 0.37, 0.42, 0.62, and 0.57, respectively. Previously, studies of sib pairs with sickle cell disease and isolated family studies showed that high levels of Hb F and FC tend to be inherited. Here, our classical twin study demonstrated that the variance of FC levels in healthy adults is largely genetically determined. (Blood. 2000;95:342-346)

Community perceptions of allowable counterforce in self-defense and defense of property.

What level of force do people believe is appropriate to use in self-defense and defense of property? One answer is that a person may use only the bare minimum of force necessary to terminate the threat in self-defense and must retreat if it is possible. One may not use deadly force in defense of property since that would be disproportionate. This set of rules is in the Model Penal Code (MPC). The current research explores the patterning of lay views about the use of counterforce in defense of self and property. Several New Jersey samples (N = 197 total) made liability ratings for four self-defense and four property defense case vignettes that differed in their underlying rationales for action. For both the self-defense and property defense cases, participants gave much lower sentences for cases in which a person kills a thief who is stealing his car, kills an unarmed attacker, or kills an attacker even when he could safely retreat, as compared to a control case in which the person is killed in response to a trivial threat. Participants' sentencing ratings were predicted by their beliefs about whether the force the defender used in the situation was necessary. In addition, participants who lacked confidence in the ability of the criminal justice system to protect them and their property recommended shorter sentences; those with less confidence in the system seemed to believe that a person should not be punished as much for taking the law into his own hands. Further results suggest that participants believed that their sentencing judgments mirrored the New Jersey Criminal Code, modeled after the MPC, although they were actually discrepant from it. We consider implications of these results for legal codes.

Methods for the study of evil-doing actions.

For obvious ethical reasons, experimental studies of severe harm-doing actions are precluded. What methods are available to experimental social psychologists for the study of harm- and evil-doing activities? Three are suggested: experiments that may have a component of role-playing but still can illuminate nodes in the socialization into harm-doing process, probes into the conceptual world of individuals who are enlisted into real-world harm-doing socialization processes, and secondary analyses of case studies written by those who have been caught up in harm doing. The methodological limits of each activity are examined, and it is argued that an approach in which combinations of methods are employed to arrive at theoretical constructions can both support generalizations that provide insights into the socialization process and be sufficiently rigorous to support prudent social action recommendations.

Community attitudes on the family of issues surrounding the death of terminal patients.

In two studies, respondents made recommendations for the medical treatment of a terminally ill elderly woman. The woman was or was not experiencing intractable pain, and had requested either heroic medical efforts or euthanasia. Respondents' recommendations were influenced by both the specific wishes of the patient and the pain the person was experiencing. However, participants were not completely swayed by the patient's wishes: only about half of the sample recommended euthanasia even when the patient was in intractable pain and had requested death; also, many subjects would not resuscitate the patient whose heart or lungs failed, even though she had requested heroic measures. Respondent attitudes toward euthanasia predicted recommendations in the expected directions. We suggest that there is less dissent on the issues that arise for medical treatments at the end of life than has been widely assumed.

Folate and vitamin B12 concentrations in maternal and fetal blood, and amniotic fluid in second trimester pregnancies complicated by neural tube defects.

OBJECTIVE: To investigate maternal and fetal folate and vitamin B12 concentrations in pregnancies affected by neural tube defects (NTD). DESIGN: Measurement of folate and vitamin B12 concentrations in amniotic fluid, fetal blood and maternal blood samples in midgestation. SUBJECTS: 32 women undergoing termination of pregnancy at 14-21 weeks gestation for social reasons (n = 24) or for fetuses with neural tube defects (n = 8). INTERVENTIONS: Fetoscopy before intra-amniotic injection of prostaglandins. RESULTS: In normal pregnancies there was a positive correlation between maternal and fetal serum folate, and the fetal serum and red blood cell folate concentrations were higher than the maternal. There were no differences in amniotic fluid, maternal blood or fetal blood folate concentrations between pregnancies with NTD and normal pregnancies. Although amniotic fluid vitamin B12 was lower in pregnancies with NTD, maternal serum vitamin B12 concentration was not reduced. CONCLUSION: In this small group of pregnancies with NTD at mid-gestation there is no evidence to suggest folate or vitamin B12 deficiency.

Multiple audience problem: a strategic communication perspective on social perception.

Examined how communicators send mixed messages containing an explicit surface content and a covert hidden content. In Study 1, Ss wrote constrained essays presenting either an introverted or extraverted personality. Although authors reported manipulating essay credibility and readers reported relying on credibility to make their judgments, readers succumbed to correspondence bias. In Studies 2 and 3, Ss again prepared either constrained essays (Study 2) or constrained videotapes (Study 3) and included in them a hidden message that would be understood by only their friends but not by strangers. Observers then read these essays or watched these videotapes. Friends detected and decoded the hidden messages, whereas strangers did not. We discuss these findings in terms of social perception and strategic communication.

Development differences in decoding the meanings of the appraisal actions of teachers.

Teachers convey evaluations through such "appraisal actions" as ability versus effort attributions for children's performance, spontaneous displays of warmth versus matter-of-fact acceptance, and attention versus inattention. Some appraisal actions (e.g., ability-effort) require an understanding of multiplicative relations to arrive at an "adult" interpretation. Others (e.g., attention-inattention) do not. First through sixth graders watched videotaped scenes in which teachers attributed one child's performance to ability but chided another for lack of effort even though he had given an equivalent performance, hugged one child but not another for equivalent performance, and paid attention to one child's oral report but not another's. Younger students (ages 5-9 to 7-10) rated the ability-attributed and hugged children as smarter; older students (ages 9-9 to 11-10) rated the effort-attributed and unhugged children as smarter. In contrast, no age differences were found in decoding attention versus inattention. The results suggest that younger children use a different strategy in decoding the meanings of complex appraisal actions.

Perceiving choice and constraint: the effects of contextual and behavioral cues on attitude attribution.

We examined how features of the situation and the target's behavior in the attitude-attribution paradigm may lead observers to infer that the behavior was performed purposefully and how these perceptions may contribute to correspondence bias. Experiment 1 demonstrated that cues suggesting that essay assignment resulted from the target's purposeful action lead to correspondent inferences. When these cues were absent, observers' inferences were not correspondent. Experiment 2 demonstrated that observers are sensitive to cues emitted by the target (facial expressions of delight and disappointment) and that those cues' meaning depends on the context in which they take place. When the essay was freely chosen, the expression had little effect; observers judged that the essay accurately reflected the target's attitudes. When the essay assignment was constrained, observers used the expressions to discount the essay when judging the target's attitudes. We discuss the implications of these findings for the study of correspondent inferences and correspondence bias.

Appraising the threat of illness: a mental representational approach.

This article (a) describes a mental model underlying initial evaluations of illness signs and (b) reports an experiment demonstrating the model's utility by showing how the model represents evidence of defensiveness among people who test positively for a sign of illness. The model consists of a set of cognitive elements that people consider to evaluate the threat represented by a sign of possible illness. Seventy-two undergraduates were led to believe that they tested positively or negatively on a saliva test for a fictitious risk factor for a disease. In addition, half the participants were told about the existence of a simple preventive treatment for the disease, whereas the others were not. Subsequently the participants answered questions about elements of the threat-appraisal model. Analysis of their responses reveals evidence of defensiveness on several elements of the model. Those testing positively for the risk factor, especially those uninformed about its treatment, minimized threat by (a) increasing their estimates of the false-positive rate of the test, (b) decreasing their estimates of the seriousness of the risk factor, and (c) decreasing their estimates of the extent to which the disease itself is life-threatening. Applications of the model to actual illness threats and the relation between threat-related judgments and health-related behavior are discussed.

Haemolysis affects insulin but not C-peptide immunoassay.

Venous blood was taken at the end of a glucose infusion test in 19 individuals and divided into four aliquots, 3 of which were variably haemolysed by repeated passage through a 23-gauge needle to simulate traumatic venepuncture. Plasma insulin (measured by both a charcoal separation and a double-antibody method), C-peptide, and haemoglobin were measured in each aliquot, and haemolysis was also assessed visibly. A significant loss of immuno-assayable plasma insulin was found in samples with only a trace of visible haemolysis, with up to 90% lost in severely haemolysed samples. Plasma C-peptide was unaffected by haemolysis. This represents an additional advantage for the use of plasma C-peptide in assessing insulin secretion.

Hematologic and biosynthetic studies in homozygous hemoglobin Constant Spring.

The elongated alpha-globin chains of hemoglobin Constant Spring (alpha cs chain of HbCS ) are produced in low amounts such that the alpha cs-gene acts as a form of alpha-thalassemia; yet in the homozygous state the pathophysiological effects of this mutant are more severe than in the corresponding conditions that result from alpha-globin gene deletions. In studies designed to examine this discrepancy, we have demonstrated that a significant proportion of red cells produced in an HbCS homozygote has a much reduced red cell life span. Contrary to previous reports, we have been able to demonstrate the expected deficit in alpha-chain production in this condition and have shown that both the cessation of globin chain synthesis in vitro and the destruction of the excess beta-chains occur unusually rapidly. Comparison with various deletion forms of alpha-thalassemia suggests that, in terms of intracellular globin chain precipitates and free beta-chain pool, homozygous HbCS red cells more closely resemble those of HbH disease, with three of the four alpha-genes inactivated, than they do the more comparable alpha-thalassemia carriers with only two genes deleted.