Lexical and Grammatical Processing of Unshadowed Messages: A Re-Examination of the Mackay Effect

Mackay (1973) claimed to have provided evidence that subjects could process the grammatical structure and lexical content of nonshadowed messages. In the present study, it was found impossible to repeat Mackay's findings when controls for several factors that had been ignored in Mackay's study were employed. Subsequent experiments indicated that two major factors contributing to Mackay's results were that he had a gap between sentences in his experiment and that the nonshadowed material came out of a background of silence. Both of these probably enabled subjects to switch attention to the nonshadowed material without disruption of shadowing performance.

Component Problems in Dichotic Listening

The experiments reported examined monitoring for semantically defined targets whilst concurrently shadowing (Experiment I) or listening silently (Experiment II). The word lists for monitoring were either visual or auditory. Monitoring and shadowing accuracy showed less interference when presentation was bimodal than when it was dichotic. However, monitoring latency and recognition memory for shadowed material did not show this effect. It is argued that these data reveal the existence of a number of different sources of potential difficulty in dichotic listening situations and the nature of these is discussed.

The use of oral fluids to monitor key pathogens in porcine respiratory disease complex

Background

The usefulness of oral fluid (OF) sampling for surveillance of infections in pig populations is already accepted but its value as a tool to support investigations of porcine respiratory disease complex (PRDC) has been less well studied. This study set out to describe detection patterns of porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), swine influenza virus type A (SIV) and Mycoplasma hyopneumoniae (M. hyo) among farms showing differing severity of PRDC.

The study included six wean-to-finish pig batches from farms with historical occurrence of respiratory disease. OF samples were collected from six pens every two weeks from the 5^th to the 21^st week of age and tested by real time PCR for presence of PRRSV, SIV and M. hyo and by quantitative real time PCR for PCV2. Data was evaluated alongside clinical and post-mortem observations, mortality rate, slaughter pathology, histopathology, and immunohistochemistry testing data for PCV2 antigen where available.

Results

PRRSV and M. hyo were detectable in OF but with inconsistency between pens at the same sampling time and within pens over sequential sampling times. Detection of SIV in clinical and subclinical cases showed good consistency between pens at the same sampling time point with detection possible for periods of 2–4 weeks. Quantitative testing of OF for PCV2 indicated different patterns and levels of detection between farms unaffected or affected by porcine circovirus diseases (PCVD). There was good correlation of PCR results for multiple samples collected from the same pen but no associations were found between prevalence of positive test results and pen location in the building or sex of pigs.

Conclusions

Detection patterns for PRRSV, SIV and M. hyo supported the effectiveness of OF testing as an additional tool for diagnostic investigation of PRDC but emphasised the importance of sampling from multiple pens and on multiple occasions. Preliminary evidence supported the measurement of PCV2 load in pooled OF as a tool for prediction of clinical or subclinical PCVD at farm level.

Social influences on unconscious plagiarism and anti-plagiarism

People are more likely to unconsciously plagiarise ideas from a same-sex partner than a different-sex partner, and more likely to unconsciously plagiarise if recalling alone rather than in the presence of their partner [Macrae, C. N., Bodenhausen, G. V., & Calvini, G. (1999). Contexts of cryptomnesia: May the source be with you. Social Cognition, 17, 273-297. doi: 10.1521/soco.1999.17.3.273 ]. Two sets of experiments explore these phenomena, using extensions of the standard unconscious plagiarism paradigm. In Experiment 1A participants worked together in same- or different-sex dyads before trying to recall their own ideas or their partner's ideas. More source errors were evident for same-sex dyads (Experiment 1A), but this effect was absent when participants recalled from both sources simultaneously (Experiment 1B). In Experiment 2A, participants recalled ideas from a single source either alone or in the presence of the partner, using an extended-recall task. Partner presence did not affect the availability of ideas, but did reduce the propensity to report them as task compliant, relative to a partner-present condition. Simultaneous recall from both sources removed this social effect (Experiment 2B). Thus social influences on unconscious plagiarism are apparent, but are influenced by the salience of the alternate source at retrieval.

Professionalism dilemmas, moral distress and the healthcare student: insights from two online UK-wide questionnaire studies

OBJECTIVE

To understand the prevalence of healthcare students' witnessing or participating in something that they think unethical (professionalism dilemmas) during workplace learning and examine whether differences exist in moral distress intensity resulting from these experiences according to gender and the frequency of occurrence.

DESIGN

Two cross-sectional online questionnaires of UK medical (study 1) and nursing, dentistry, physiotherapy and pharmacy students (study 2) concerning professionalism dilemmas and subsequent distress for (1) Patient dignity and safety breaches; (2) Valid consent for students' learning on patients; and (3) Negative workplace behaviours (eg, student abuse).

PARTICIPANTS AND SETTING

2397 medical (67.4% female) and 1399 other healthcare students (81.1% female) responded.

MAIN RESULTS

The most commonly encountered professionalism dilemmas were: student abuse and patient dignity and safety dilemmas. Multinomial and logistic regression identified significant effects for gender and frequency of occurrence. In both studies, men were more likely to classify themselves as experiencing no distress; women were more likely to classify themselves as distressed. Two distinct patterns concerning frequency were apparent: (1) Habituation (study 1): less distress with increased exposure to dilemmas 'justified' for learning; (2) Disturbance (studies 1 and 2): more distress with increased exposure to dilemmas that could not be justified.

CONCLUSIONS

Tomorrow's healthcare practitioners learn within a workplace in which they frequently encounter dilemmas resulting in distress. Gender differences could be respondents acting according to gendered expectations (eg, males downplaying distress because they are expected to appear tough). Habituation to dilemmas suggests students might balance patient autonomy and right to dignity with their own needs to learn for future patient benefit. Disturbance contests the 'accepted' notion that students become less empathic over time. Future research might examine the strategies that students use to manage their distress, to understand how this impacts of issues such as burnout and/or leaving the profession.

How much exposure to English is necessary for a bilingual toddler to perform like a monolingual peer in language tests?

BACKGROUND

Bilingual children are under-referred due to an ostensible expectation that they lag behind their monolingual peers in their English acquisition. The recommendations of the Royal College of Speech and Language Therapists (RCSLT) state that bilingual children should be assessed in both the languages known by the children. However, despite these recommendations, a majority of speech and language professionals report that they assess bilingual children only in English as bilingual children come from a wide array of language backgrounds and standardized language measures are not available for the majority of these. Moreover, even when such measures do exist, they are not tailored for bilingual children.

AIMS

It was asked whether a cut-off exists in the proportion of exposure to English at which one should expect a bilingual toddler to perform as well as a monolingual on a test standardized for monolingual English-speaking children.

METHODS & PROCEDURES

Thirty-five bilingual 2;6-year-olds exposed to British English plus an additional language and 36 British monolingual toddlers were assessed on the auditory component of the Preschool Language Scale, British Picture Vocabulary Scale and an object-naming measure. All parents completed the Oxford Communicative Development Inventory (Oxford CDI) and an exposure questionnaire that assessed the proportion of English in the language input. Where the CDI existed in the bilingual's additional language, these data were also collected.

OUTCOMES & RESULTS

Hierarchical regression analyses found the proportion of exposure to English to be the main predictor of the performance of bilingual toddlers. Bilingual toddlers who received 60% exposure to English or more performed like their monolingual peers on all measures. K-means cluster analyses and Levene variance tests confirmed the estimated English exposure cut-off at 60% for all language measures. Finally, for one additional language for which we had multiple participants, additional language CDI production scores were significantly inversely related to the amount of exposure to English.

CONCLUSIONS & IMPLICATIONS

Typically developing 2;6-year-olds who are bilingual in English and an additional language and who hear English 60% of the time or more, perform equivalently to their typically developing monolingual peers.

Posttraumatic stress disorder following myocardial infarction: personality, coping, and trauma exposure characteristics

OBJECTIVE

This study aimed to investigate the interrelationship between trauma exposure characteristics of myocardial infarction (MI), MI patients' personality traits, coping strategies, post-MI PTSD, and general psychological distress.

METHOD

One hundred and twenty MI patients were recruited from two general practices. The MI patients were interviewed using a MI experience questionnaire and completed the Posttraumatic Stress Diagnostic Scale (PDS), the General Health Questionnaire-28 (GHQ-28), the NEO-Five Factor Inventory (NEO-FFI), and the COPE Scale.

RESULTS

Neuroticism was directly associated with post-MI PTSD and general psychological distress, while agreeableness did not link to the outcomes directly. Neuroticism influenced MI exposure characteristics which in turn influenced PTSD. Agreeableness affected PTSD and general psychological distress through MI exposure characteristics. Neuroticism influenced problem-focused coping which in turn affected general psychological distress. Agreeableness influenced problem-focused coping which in turn affected PTSD and general psychological distress.

CONCLUSIONS

Patients developed PTSD and general psychological distress following MI. Neurotic and antagonistic personality traits combined with patients' subjective experiences of MI and usage of problem-focused coping influenced the severity of outcomes.

Do stimulus--action associations contribute to repetition priming?

Despite evidence that response learning makes a major contribution to repetition priming, the involvement of response representations at the level of motor actions remains uncertain. Levels of response representation were investigated in 4 experiments that used different tasks at priming and test. Priming for stimuli that required congruent responses across 2 tasks was compared with that for stimuli requiring incongruent responses. Congruent responses showed more priming than incongruent responses did when congruence involved both decisions and actions (Experiment 1), decisions only (Experiment 2), and actions only (Experiment 4) but not when decision and action congruence were set in opposition (Experiment 3). These results demonstrate response learning with response representations at the level of both decisions and actions.

The Role of Working Memory Capacity in Multiple-Cue Probability Learning

Multiple-cue probability learning (MCPL) involves learning to predict a criterion when outcome feedback is provided for multiple cues. A great deal of research suggests that working memory capacity (WMC) is involved in a wide range of tasks that draw on higher level cognitive processes. In three experiments, we examined the role of WMC in MCPL by introducing measures of working memory capacity, as well as other task manipulations. While individual differences in WMC positively predicted performance in some kinds of multiple-cue tasks, performance on other tasks was entirely unrelated to these differences. Performance on tasks that contained negative cues was correlated with working memory capacity, as well as measures of explicit knowledge obtained in the learning process. When the relevant cues predicted positively, however, WMC became irrelevant. The results are discussed in terms of controlled and automatic processes in learning and judgement.

Trauma exposure characteristics, past traumatic life events, coping strategies, posttraumatic stress disorder, and psychiatric comorbidity among people with anaphylactic shock experience

OBJECTIVES

This study investigated the interrelationship between trauma exposure characteristics, past traumatic life events, coping strategies, posttraumatic stress disorder (PTSD) symptoms, and psychiatric comorbidity among people after anaphylactic shock experience.

METHOD

The design was cross-sectional in that 94 people with anaphylactic shock experience responded to a postal survey. They completed the Posttraumatic Stress Disorder Checklist, the General Health Questionnaire 28, and the COPE Scale. They also answered questions on trauma exposure characteristics. The control group comprised 83 people without anaphylaxis.

RESULTS

Twelve percent of people with anaphylactic shock experience fulfilled the diagnostic criteria for full PTSD. As a group, people with anaphylaxis reported significantly more past traumatic life events and psychiatric comorbidity than did the control. Partial least squares analysis showed that trauma exposure characteristics influenced postanaphylactic shock PTSD symptoms and psychiatric comorbidity, which, in turn, influenced coping strategies.

CONCLUSIONS

People could develop PTSD and psychiatric comorbidity symptoms after their experience of anaphylactic shock. The way they coped with anaphylactic shock was affected by the severity of these symptoms. Past traumatic life events had a limited role to play in influencing outcomes.

The effects of precedence on Navon-induced processing bias in face recognition

Macrae and Lewis (2002) showed that repeated reporting of the global dimension of Navon stimuli improved performance in a subsequent face identification task, whilst reporting the features of the Navon stimuli impaired performance. Using a face composite task, which is assumed to require featural processing, Weston and Perfect (2005) showed the complementary pattern: Featural responding to Navon letters speeded performance. However, both studies used Navon stimuli with global precedence, in which the overall configuration is easier to report than the features. Here we replicate the two studies above, whilst manipulating the precedence (global or featural) of the letter stimuli in the orientation task. Both studies replicated the previously reported findings with global precedence stimuli, but showed the reverse pattern with local precedence stimuli. These data raise important questions as to what is transferred between the Navon orientation task and the face-processing tasks that follow.

Medical students' attitudes to complementary and alternative medicine: further validation of the IMAQ and findings from an international longitudinal study

BACKGROUND

Current research mainly employs cross-sectional designs to examine changes in medical students' attitudes towards complementary and alternative medicine (CAM).

AIMS

This paper reports the findings of a longitudinal study to further validate the Integrative Medicine Attitude Questionnaire (IMAQ) and examine changes in medical students' attitudes over 3 years.

METHODS

A total of 154 medical students from four schools in three countries completed a modified version of the IMAQ during their first (T1) and fourth year (T2).

RESULTS

We established the validity of a three-factor model for the IMAQ: (1) attitudes towards holism; (2) attitudes towards the effectiveness of CAM therapies, and (3) attitudes towards introspection and the doctor-patient relationship. We found that IMAQ factor scores did not differ significantly from T1 to T2, emphasizing the relative stability in attitudes across time. Various student characteristics were significantly associated with IMAQ factor scores at T2: age, gender, CAM use, CAM education and school; and two variables (gender and CAM use) predicted changes in medical students' attitudes between T1 and T2.

CONCLUSIONS

We urge medical educators to continue exploring medical students' attitude changes towards CAM and we provide examples of what further research is needed.

Sizing up the associative account of repetition priming

Three studies which test an associative account of repetition priming in a size comparison task are reported. Congruence of decision between priming and test affected performance when the priming task and test tasks were the same but not when they differed. This congruence effect was unaffected by the proportion of trials with congruent responses. Same-task priming exceeded cross-task priming even when both tasks required the same aspect of semantic knowledge. The results indicate that a component of priming is due to associations which are formed during priming and automatically activated when stimuli are repeated at test. Stimuli do not become associated with motor responses but are associated with the results of processing at a number of other levels.

Content specificity: is it the full story? Statistical modelling of a clinical skills examination

OBJECTIVE

This study sought to determine the relative contributions made by transferable skills and content-specific skills to Year 2 medical student performance in a clinical skills examination.

METHODS

Correlated trait-correlated method models were constructed to describe the performance of 2 year groups of students in examinations held in the summers of 2004 and 2005 at Peninsula Medical School in the UK. The transferable skills components of the models were then removed to indicate the contribution made to the fit of the models to the data.

RESULTS

Although content-specific skills made the greater contribution to the 2 models of student performance (accounting for averages of 54% and 43% of the variance, respectively), transferable skills did make an important but smaller contribution (averages of 13% and 16%, respectively). When the transferable skills components of the models were removed, the fit was not as good.

CONCLUSIONS

Both content-specific skills and transferable skills contributed to performance in the clinical skills examination. This challenges current thinking and has important implications, not just for those involved in clinical skills examinations, but for all medical educators.

The effects of local and global processing orientation on eyewitness identification performance

Recent work has demonstrated that performance on a simultaneous target-present photographic line-up can be enhanced by prior global processing orientation, and hindered by prior local processing orientation induced by processing Navon letter stimuli. A series of studies explore the generality of this processing bias effect using either videotaped scenarios or live interactions. Five experiments demonstrate that these effects are seen across a range of test stimuli, test formats, and test instructions. These data inform the processes engaged in by witnesses when making line-up identifications and indicate that it may be possible to improve the accuracy of witnesses making such judgements.

Halo effects in grading student projects

Halo effects in rating specific pieces of work, as in educational grading, have received little attention. Grades awarded by 2 independent graders to undergraduate projects were analyzed with a correlated uniqueness model. Grades showed substantial halo despite being awarded by expert assessors at the time of reading the work. There was greater halo between different grades applying to the same section of the project than between grades applying to different sections. Supervisors who had regular contact with the student whose work they were grading showed no more halo than other graders. More reliable graders showed less within-section halo than graders of lower reliability but equal between-sections halo. The halo effects observed cannot be entirely attributable to a unitary general impression.

Local temporal distinctiveness does not benefit auditory verbal and spatial serial recall

In the present study, we examined the role of randomly arranged temporal intervals preceding and following items (pre- and postitem intervals, respectively) in auditory verbal and spatial recall tasks. The duration of the pre- and postitem intervals did not affect serial recall performance. This finding calls into question (1) the suggestion that the interval following an item permits the consolidation of information in memory, even in a relatively demanding spatial task, and (2) the prediction that temporal distinctiveness should improve performance. The latter was explored further by showing that in contrast to our empirical data, a relative temporal distinctiveness model produced significant increases in recall performance when pre- and postitem intervals increased. The results are discussed with regard to recent studies revisiting the role of temporal isolation in short-term serial memory.

Multischool, international survey of medical students' attitudes toward "holism"

PURPOSE

Core and optional courses of study in complementary and alternative medicine (CAM) are being incorporated into medical curricula. The authors carried out this study to validate a tool to examine students' attitudes toward holism and CAM and explore the relationships between their attitudes and other demographic and education-related characteristics in a large, multischool, international sample of medical students.

METHOD

In 2003 the authors used a modified version of the Integrated Medicine Attitude Questionnaire (IMAQ) to survey students at a total of six medical schools in the United Kingdom, New Zealand, Canada, the United States, and Hong Kong, China. A three-factor model was tested using confirmatory factor analysis, and the internal consistency of the factors were identified using Cronbach's alpha coefficients. A multiple-indicator multiple-cause (MIMIC) analysis was carried out to determine the relationship between IMAQ factors and student characteristics.

RESULTS

The authors validated a three-factor model for the IMAQ: (1) attitudes toward holism, (2) attitudes toward the effectiveness of CAM, and (3) attitudes toward introspection and the doctor-patient relationship. Cronbach's alpha coefficients ranged from .41 to .71. The MIMIC model indicated that various background variables were associated with IMAQ factors (gender, race/ethnicity, and school), depending on whether students had previously visited a CAM practitioner and whether students were willing to undertake a special study module in CAM.

CONCLUSIONS

Further development work on the IMAQ is required and qualitative research to verify and examine the reasons behind the relationships found in this study between students' attitudes to holism and their demographic and education-related characteristics.

A multiple-indicator multiple-cause model for posttraumatic stress reactions: personality, coping, and maladjustment

OBJECTIVE

This study aimed to develop a multiple-indicator multiple-cause model (MIMIC) to describe the relationship among posttraumatic stress (PTSD) responses, general health problems, death anxiety, personality factors, and coping strategies among community residents exposed to the technological disasters of aircraft and train crashes.

MATERIALS AND METHODS

One hundred forty-eight community residents, after exposure to the aircraft or train crash, were assessed using the Impact of Event Scale, the General Health Questionnaire-28, the Death Anxiety Scale, the Eysenck Personality Questionnaire, and the Ways of Coping Checklist. The control group (n = 90) comprised members of the general public, who had not been exposed to the disasters, from another city.

RESULTS

The model showed significant associations between the impact of the disaster and general health problems, which varied depending on where community residents lived in relation to the disaster site, whether they were present when the disaster occurred, and the type of disaster. The model also suggested that death anxiety was associated with type of disaster and neuroticism. The model supported the interactive model in that personality factors interacted with coping strategies in maintaining or generating PTSD and general health problems.

CONCLUSIONS

After exposure to technological disasters, community residents could develop PTSD and general health problems; however, increased death anxiety was a separate psychological reaction. The interaction between certain personality traits and coping strategies was one reason for PTSD and general health problems.

Differentiating posttraumatic stress between elderly and younger residents

This study aimed to differentiate between the posttraumatic stress responses of elderly and younger community residents who had been exposed to two technological disasters (a train collision and an aircraft crash). One hundred and forty-eight community residents were assessed using the Impact of Event Scale (IES) and the General Health Questionnaire (GHQ-28). The results showed that age differences were not affected by impact of disaster (IES), suggesting that elderly and younger community residents responded to the disasters similarly. Instead, the community residents exposed to the aircraft crash experienced significantly more intrusion and avoidance than those exposed to the train collision. Also, the community residents who had experienced high exposure to the disasters had significantly more intrusive thoughts and exhibited significantly more avoidance behavior than the low/medium exposure group. The results also showed no main effects in general health between the elderly and younger community residents, suggesting that their health status was similar. Instead, the community residents exposed to the aircraft crash had significantly more general health problems than the train disaster residents and the control group. Also, the community residents in either the low/medium or the high exposure group experienced more general health problems than the control group. Correlation coefficients showed that intrusion, avoidance, and the total impact of the disasters were significantly correlated with all general health subscales for both elderly and younger groups.

Approaches to learning and studying in medical students: validation of a revised inventory and its relation to student characteristics and performance

INTRODUCTION

Inventories to quantify approaches to studying try to determine how students approach academic tasks. Medical curricula usually aim to promote a deep approach to studying, which is associated with academic success and which may predict desirable traits postqualification.

AIMS

This study aimed to validate a revised Approaches to Learning and Studying Inventory (ALSI) in medical students and to explore its relation to student characteristics and performance.

METHODS

Confirmatory factor analysis was used to validate the reported constructs in a sample of 128 Year 1 medical students. Models were developed to investigate the effect of age, graduate status and gender, and the relationships between approaches to studying and assessment outcomes.

RESULTS

The ALSI performed as anticipated in this population, thus validating its use in our sample, but a 4-factor solution had a better fit than the reported 5-factor one. Medical students scored highly on deep approach compared with other students in higher education. Graduate status and gender had significant effects on approach to studying and a deep approach was associated with higher academic scores.

CONCLUSIONS

The ALSI is valid for use in medical students and can uncover interesting relationships between approaches to studying and student characteristics. In addition, the ALSI has potential as a tool to predict student success, both academically and beyond qualification.

Associative processes in repetition priming

Three experiments that investigated alternative accounts of repetition priming are reported. All 3 experiments used semantic comparison tasks and included trials in which each of the 2 words being compared had previously occurred on separate trials. In the re-pair match condition, the response required matched that on the 2 previous trials in which the words had occured. In there-pair mismatch condition, the response required was opposite to that on the previous trials containing the words forming the critical pair. In all 3 experiments, responses were faster and more accurate in the re-pair match condition than in the re-pair mismatch condition. Possible accounts of this effect within the frameworks of instance theory and of transfer appropriate processing are considered.

Explicit and implicit processes in multicue judgment

In two experiments, a multicue probability learning task was used to train participants in relating judgments to a criterion, on the basis of several cues that could or could not be relevant. The outcome feedback had 25% added noise to simulate real-world experience-based learning. Judgmental strategies acquired were measured by individual multiple linear regression analyses of a test phase (with no feedback) and were compared with self-ratings of cue relevance. In a third experiment, participants were instructed explicitly on cue relevance, with no training phase. The pattern of results suggested that both implicit and explicit cognitive processes influenced judgments and that they may have been sensitive to different task manipulations in the learning phase. On more complex tasks, despite weak explicit learning, explicit processes continued to influence judgments, producing a decrement in performance. These findings explain why studies of expert judgment often show only moderate levels of self-insight, since people have only partial access to the processes determining their judgments.

Oxygen administration and explicit memory: no improvement found in healthy volunteers

It has been suggested that oxygen administration to healthy volunteers could improve their memory. We tested this hypothesis with a twin, double crossover, placebo-controlled study in 20 healthy non-smokers, allocated randomly to one of two groups. Blinded to the nature of the gas, group A breathed air first then oxygen on day 1, and then oxygen first, followed by air on day 2. Group B had all exposures in reverse order. After each gas exposure a written memory test with a list of 20 words was carried out and evaluated by a blinded observer. Recall after oxygen exposure (mean 8.3 words) was not significantly different from that after air exposure (mean 9 words).

Phase I and pharmacokinetic study of DACA (XR5000): a novel inhibitor of topoisomerase I and II. CRC Phase I/II Committee

DACA, also known as XR5000, is an acridine derivative active against both topoisomerase I and II. In this phase I study, DACA was given as a 3-h intravenous infusion on 3 successive days, repeated every 3 weeks. A total of 41 patients were treated at 11 dose levels between 9 mg m(-2) d(-1) and the maximum tolerated dose of 800 mg m(-2) day(-1). The commonest, and dose-limiting, toxicity was pain in the infusion arm. One patient given DACA through a central venous catheter experienced chest pain with transient electrocardiogram changes, but no evidence of myocardial infarction. At the highest dose levels, several patients also experienced flushing, pain and paraesthesia around the mouth, eyes and nose and a feeling of agitation. Other side-effects, such as nausea and vomiting, myelosuppression, stomatitis and alopecia, were uncommon. There was one minor response but no objective responses. DACA pharmacokinetics were linear and did not differ between days 1 and 3. The pattern of toxicity seen with DACA is unusual and appears related to the mode of delivery. It is possible that higher doses of DACA could be administered using a different schedule of administration.

A new approach to exploring biases in educational assessment

This paper presents and illustrates an approach to the study of marking biases based on multi-sample confirmatory factor analysis. This is applied to the marks awarded by two independent markers to the final year dissertations of 197 female and 58 male psychology undergraduates. One of the two markers had supervised the work on which the dissertation was based on a one-to-one basis. The results suggest that about 30 per cent of the variance in the supervisor's mark is attributable to influences which are specific to the supervisor, orthogonal to the merit of the project as assessed by the two markers jointly, and general across each of the four marks awarded by the supervisor. The most plausible interpretation of these influences is that they represent a contamination of the supervisor's mark by personal knowledge of the student. These biases in the supervisor's marking were found to have more influence for male than for female students and to elevate the marks of males relative to those of females to a small but significant extent. It would be unwise to overgeneralize from these findings, but they demonstrate the potential value of this method of studying marking biases.

General practitioners' tacit and stated policies in the prescription of lipid lowering agents

BACKGROUND

Research into general practitioners' prescribing behaviour with regard to lipid lowering agents has relied on survey methods which presume that doctors have insight into their prescribing behaviour and can describe it accurately.

AIM

This study set out to measure the tacit policies used by general practitioners in prescribing lipid lowering agents and to compare these with their stated policies.

METHOD

Effects of 13 separate cues on decisions to prescribe were examined. The cues included cholesterol levels and a number of associated risk factors for coronary heart disease. Doctors rated 130 imaginary cases presented by a computer. Thirty five general practitioners in the Plymouth area participated in the study. Their ages ranged from 31 to 55 years and all but four were men. The raw data in each case was a rating of the likelihood that the doctor would prescribe for the patient described. These were converted into statistical weightings by use of multiple linear regression. The pattern of (standardized) weights constituted the tacit policy for each doctor. Stated policies were measured in a subsequent interview by asking doctors to rate the influence of each cue.

RESULTS

Both tacit and stated policies diverged widely between different doctors. Most doctors overestimated the number of cues that had actually influenced their decisions, and many believed that they had taken into account associated factors for coronary heart disease when they had not. On lifestyle related risks doctors were generally less likely to treat overweight people and most stated this as their policy. Most were also less likely to treat smokers but some had the opposite policy. Those less likely to treat smokers were also less likely to treat obese patients. There was also considerable variation in the extent to which the doctors took account of the attitude of the patient to receiving treatment.

CONCLUSION

Doctors' policies are highly variable and particularly inconsistent in the treatment of smokers. Relevant risk factors may be ignored--even though they are understood--because the risk assessment involved is too psychologically complex a task to be performed intuitively. Decision aids and clear protocols are needed in this area.

Improving auditory warning design: quantifying and predicting the effects of different warning parameters on perceived urgency

The effects of four parameters (speed, fundamental frequency, repetition units, and inharmonicity) on perceived urgency were scaled using an application of Stevens's power law. From the exponents obtained, equal units of urgency change were calculated for three parameters. The units were combined in a set of stimuli, and the order of urgency was predicted. The obtained and predicted orders of urgency were highly correlated. The results also showed that even when equalized by psychophysical techniques, some parameters contribute more to perceived urgency than do others. This may be attributable to the different types of parameters scaled or the proportion of the usable range of each parameter that represents a unit change in urgency. The implication of the work for the design and improvement of auditory warnings is discussed.

A phase I study of the left-shifting agent BW12C79 plus mitomycin C and the effect on the skeletal muscle metabolism using 31P magnetic resonance spectroscopy

BW12C79 stabilizes the oxyhemoglobin molecule resulting in a reversible left-shift of the oxygen saturation curve. The activity of a number of bioreductive anticancer drugs, such as mitomycin C, may be enhanced under hypoxic conditions. Twenty-four patients with various malignancies received BW12C79 and mitomycin C. BW12C79 was administered i.v. with a loading dose (20-50 mg/kg) over 1 h followed by a maintenance infusion of 4 mg/kg/h for 5 h. Percentage modification of the oxyhemoglobin (degree of left-shift) was dose related with maximum modification of 56% and was maintained for the duration of maintenance infusion of BW12C79. Hemoglobin electrophoresis showed a fast moving band consistent with the BW12C79-oxyhemoglobin complex. Side effects at the top dose level comprised headache, nausea/vomiting, vein irritation, and myocardial ischemia. One other patient suffered from an acute encephalopathy of unknown etiology a few days following BW12C79. 31P magnetic resonance spectroscopy of exercising calf muscles showed increased breakdown of high energy phosphate stores and a greater reduction in pH. Recovery of the high energy phosphate stores after exercise was slow. These results were consistent with reduced oxygen supply due to either a left shift of the oxygen saturation curve and/or reduced muscle blood flow. BW12C79 did not interfere with the pharmacokinetics of mitomycin C. In conclusion, this phase I study demonstrates the feasibility of achieving a significant left shift in the oxygen saturation curve in cancer patients which is maintained for at least 5 h with acceptable toxicity. The maximum tolerated dose of BW12C79 was 50 mg/kg loading infusion followed by a maintenance infusion of 4 mg/kg/h. Magnetic resonance spectroscopy results were consistent with reduced supply of oxygen to exercising skeletal muscle. BW12C79 may be of potential benefit as an adjunct to bioreductive drugs in the treatment of solid tumors.

A phase II and pharmacokinetic study with oral piritrexim for metastatic breast cancer

Piritrexim is a lipid-soluble antifolate which, like methotrexate, has a potent capacity to inhibit dihydrofolate reductase. We performed a multicentre phase II study with piritrexim in patients with locally advanced or metastatic breast cancer. Twenty-four patients of which sixteen had received prior chemotherapy, were initially treated with 25 mg piritrexim orally administered trice daily for four days, repeated weekly, with provision for dose escalation or reduction according to observed toxicity. Of twenty-one patients evaluable for tumour response, one patient achieved a partial response which lasted for 24 weeks. Three patients had stable disease during 12 weeks of treatment, seventeen had progressive disease. Pirtrexim was generally well tolerated, in eighteen patients the dose could be escalated. Myelotoxicity was the most frequent observed toxicity of this piritrexim regimen. Leucopenia and thrombocytopenia grade 3/4 occurred in 38% of the patients sometime during treatment. Pharmacokinetic analysis of piritrexim in three patients during the first treatment cycle, revealed peak levels 1 to 2 h after an oral dose, with a trend towards a higher peak plasma levels and AUCs on the fourth dosing day compared with the first dosing day. In conclusion, orally administered piritrexim appears to be a regimen with little activity in patients with locally advanced or metastatic breast carcinoma.

Tumour concentrations of flavone acetic acid (FAA) in human melanoma: comparison with mouse data

Flavone acetic acid (FAA) showed impressive effects against murine solid tumours but no activity in clinical studies. The mechanism of action in mice may involve damage to tumour vasculature or immunomodulation, and these effects may be species-specific. Alternatively, concentrations of FAA achieved in mouse tumours may be higher than in human tumours. It is important to resolve this issue since it raises important questions about the relevance of in vitro versus in vivo tumour screens and the development of FAA analogues. As part of a Cancer Research Campaign Phase II study of metastatic melanoma in which 8.4 g m-2 FAA was given as a 6 h infusion, six tumour biopsies were obtained from four patients. FAA tumour concentrations were determined by HPLC and compared with subcutaneous murine solid tumours within the same analytical laboratory. Tumour/plasma percentages (range 26-61%; mean +/- SD, 43.9 +/- 11.4%) were similar to those in mice, as was the area under the curve (AUC) extrapolated to infinity and the AUC above the putative activity threshold of 100 micrograms ml-1. We conclude that the exposure of drug-refractory human melanoma tissue to FAA was comparable to that of sensitive mouse tumours. This suggests that reduced penetration of FAA into human tumours is unlikely to explain the lack of antitumour activity observed in clinical studies and that differences in mechanism of action are predominant.

Phase I study of BW12C in combination with mitomycin C in patients with advanced gastrointestinal cancer

The effect of combining the oxyhemoglobin-modifying drug BW12C with mitomycin C was investigated in a Phase I study of 18 patients with advanced gastrointestinal cancer. The dose of BW12C was increased from 20 mg/kg to 50 mg/kg to modify the hemoglobin-oxygen saturation curve by up to 48%. The period of maximum modification was then prolonged for up to 3 hr by a maintenance infusion of 4-6 mg/kg/hr. Pharmacokinetics of BW12C and mitomycin C were performed in all patients. Peak levels of BW12C increased from 139 micrograms/ml to 378 micrograms/ml. Plasma half life was independent of dose, with an average of 3.3 hr. BW12C was well tolerated with no severe side effects. Three patients had objective tumour responses.

Reading without phonology?

Responses to items such as brane are slower and/or more error prone than responses to items such as slint in lexical decision (is this string spelt like a real word?). The received view is that this “pseudohomophone” effect is attributable to phonological receding. Taft (1982) has challenged this view, offering instead a grapheme-grapheme account which assumes that graphemes that map onto a common phoneme develop the ability to activate each other without reference to phonological mediation.

Taft's grapheme-grapheme account is tested in two experiments. Experiment 1 shows that the presentation of a pseudohomophone facilitates the response to a subsequently presented word (e.g., groce–gross). Experiment 2 shows that nonword letter strings that are translatable into words by the application of putative grapheme-grapheme rules (e.g., gloce–gloss) produce no facilitation. These results are consistent with the notion of a phonological influence but inconsistent with the grapheme–grapheme account. Loci for this pseudohomophone priming effect are discussed.