Psychometric properties of self-report measures of eating disorder cognitions: a systematic review

BACKGROUND

Although eating disorder (ED) models display some differences in theory and treatment approach, cognitive-behavioural, schema-focused, and disorder-specific models all highlight the fundamental nature of cognitions as key factors in ED development and maintenance processes. As such, it is vital that ED cognitions continue to be assessed and monitored as therapeutic targets and treatment outcomes as well as being examined as constructs in empirical research. This review aimed to systematically identify and evaluate the psychometric properties of existing self-report measures of ED cognitions.

METHODS

A systematic review protocol was registered using the international prospective register of systematic reviews (PROSPERO; CRD42023440840). Included studies described the development, validation and/or the psychometric evaluation of a measure (or subscale) that was specifically developed to solely assess ED cognitions (that is thoughts, expectations, assumptions, or beliefs), in English-speaking, adult populations. The search was conducted using three electronic databases: PsycINFO, MedLine, and Embase. Two independent reviewers conducted screening, selection and evaluation of the psychometric properties of relevant measures using a standardised, well-established quality appraisal tool.

RESULTS

Of the initial search of 7581 potential studies, 59 met inclusion criteria and described the psychometric evaluation of 31 measures (or subscales) of ED cognitions. The findings from the current review indicate that of the included measures, none currently meet all nine criteria of adequate psychometric properties. The Eating Beliefs Questionnaire (EBQ; and EBQ-18), and the Eating Disorder Inventory Body Dissatisfaction subscale (EDI [BD]) currently possess the most evidence supporting their validity, reliability, and clinical utility.

CONCLUSIONS

The findings of the current systematic review provide guidance for future researchers to focus efforts on improving evidence for the validity, reliability and utility of self-report measures of ED cognitions. Overall, the present study has provided a detailed and systematic evaluation to support researchers and clinicians in future selection of measures of ED cognitions dependent on the specific aims of their research and treatment.

Development and validation of the Pain-Induced Comfort Eating Scale in a chronic pain sample

Background

Chronic pain and higher body weight frequently co-occur. This common comorbidity is thought to be mediated by the use of comfort eating as a strategy for managing both the physical and psychological pain and discomfort associated with flare-ups of chronic pain. Valid and reliable assessment tools are needed to inform the development of effective treatments.

Aims

This study aimed to assess the psychometric properties of a new brief measure of pain-induced comfort eating in chronic pain, the Pain-Induced Comfort Eating Scale (PICES).

Methods

A sample of 166 patients with chronic pain completed an online test battery including the PICES along with measures of chronic pain and pain-related symptoms, disordered eating, and related psychological factors.

Results

Results of exploratory factor analysis revealed a single-factor model for the four-item PICES. Further, the PICES demonstrated evidence of good internal consistency as well as convergent validity with demonstrated correlations with related measures. The results of this study also revealed that comfort eating in chronic pain appears to be related to psychological distress; the PICES correlated more strongly with measures assessing mood and psychological distress compared to interference/intensity of physical pain itself. Scores on the PICES also correlated strongly with measures of uncontrolled and emotional eating.

Conclusions

Overall, our results indicate that the PICES provides a valid and useful brief measure of comfort eating in chronic pain that might be useful to inform treatments targeting the comorbid disordered eating practices that can lead to higher body weights in patients with chronic pain.

A randomised controlled trial of clinician supported vs self-help delivery of online cognitive behaviour therapy for Bulimia Nervosa

High dropout rates and poor adherence associated with digital interventions have prompted research into modifications of these treatments to improve engagement and completion rates. This trial aimed to investigate the added benefit of clinician support when paired alongside a ten-session, online cognitive behaviour therapy (CBT) self-help intervention for bulimia nervosa (BN). As part of a three-arm, phase II randomised controlled trial, 114 participants (16 years or over) with full or subthreshold BN were randomly assigned to complete the intervention in a self-help mode (with administrative researcher contact; n = 38), with adjunct clinician support (weekly 30-minute videoconferencing sessions; n = 37), or a no-treatment waitlist control (WLC; n = 39). Baseline to post-treatment (12-weeks) decreases in objective binge episode frequency were significantly greater for clinician-supported participants as compared to WLC, but not for self-help when compared to WLC. However, due to continued improvements for self-help across follow-up (24-weeks), both arms outperformed WLC when analysed as an overall rate of change across three timepoints. Clinician-supported participants outperformed self-help in regards to laxative use and dietary restraint. Our results demonstrate that good clinical outcomes can be achieved with a relatively brief online CBT-based program even in the absence of structured clinical support, indicating a possible overreliance upon clinician support as a primary adherence-facilitating mechanism.

The relationship between distress tolerance and symptoms of depression: Validation of the Distress Tolerance Scale (DTS) and short-form (DTS-SF)

OBJECTIVE

Distress tolerance (DT) has been found to be implicated in the development and maintenance of depressive symptomatology and various other significant psychological conditions. As such, it is critical to have measures of DT that are effective and easy to administer. This study aimed to examine the factor structure, psychometric properties, and clinical utility of the Distress Tolerance Scale (DTS) and the short-form version, the Distress Tolerance Scale Short-form (DTS-SF), in a large population of individuals with varying levels of self-reported depressive symptoms.

METHOD

A total of 959 participants completed an online battery of questionnaires which included an assessment of depressive symptoms as well as the DTS and related measures. Results: Confirmatory factor analyses validated the four-factor structure of the DTS and the one-factor structure of the DTS-SF. Good construct validity and good internal consistency were observed across both the DTS and DTS-SF.

CONCLUSION

Overall, this paper provides new evidence for the validity, reliability and discriminative ability of the DTS and the brief version of the questionnaire, the DTS-SF.

Psychometric properties of the state Probability and Consequences Questionnaire for social anxiety disorder

Cognitive models of social anxiety propose that overestimation of the probability and cost of negative evaluation plays a central role in maintaining the disorder. However, there are currently no self-report state-based measures of probability and cost appraisals. The current paper examines the psychometric properties of the Probability and Consequences Questionnaire for social anxiety (PCQ-SA), which measures probability and consequence appraisals both in anticipation of, and in response to, an impromptu speech task. A total of 532 participants were recruited for the present study, consisting of 409 participants with a principal diagnosis of Social Anxiety Disorder (SAD), and 123 non-clinical controls. Results of exploratory and confirmatory factor analyses supported a two-factor solution for the PCQ-SA. The PCQ-SA demonstrated excellent internal consistency, excellent test-retest reliability, good convergent validity at both time points (i.e., pre and post speech task), and sensitivity to treatment. Finally, using Receiver Operating Characteristic Curve Analysis, clinical cut-off scores were calculated for probability and consequences at both time points, with the PCQ-SA scales showing good sensitivity, specificity, and positive and negative predictive values. Overall, the results provide evidence that the PCQ-SA possesses excellent psychometric properties. The PCQ-SA is suitable for use in clinical and research settings to assess key cognitive maintaining factors for SAD.

Assessing negative core beliefs in eating disorders: revision of the Eating Disorder Core Beliefs Questionnaire

BACKGROUND

Increased theoretical and empirical attention has been given to examining the role of core beliefs in both the development and maintenance of eating disorders (EDs). The Eating Disorder Core Beliefs Questionnaire (ED-CBQ) is self-report measure designed to assess five dimensions of core beliefs relating to eating disorders; self-loathing, unassertive/inhibited, demanding/needing help and support, abandoned/deprived, and high standards for the self. The present study aimed to evaluate the psychometric properties of the ED-CBQ and to develop a revised and improved version of the original measure after evaluating its factor structure and related properties.

METHODS

A sample of undergraduate university students (N = 763) completed an online test battery of questionnaires. Putative ED-symptomatic (n = 384) and non-ED (n = 379) subgroups were created from self-reported responses from the Eating Disorder Examination Questionnaire (EDEQ). Confirmatory factor analyses (CFAs) were performed, and internal consistency, construct validity, group differences and clinical utility was examined.

RESULTS

An initial CFA did not support the original five-factor 40-item ED-CBQ. A revised version was developed that possessed equal or superior psychometric properties to the original 40-item measure. The ED-CBQ-R demonstrated superior model fit, similar levels of reliability and construct validity, and the ability to discriminate between putative ED diagnostic groups.

CONCLUSIONS

Our results suggest that the ED-CBQ-R is a valid, reliable, but more importantly an efficient and accessible measure with the potential to be utilised both clinically and in research settings.

Preventing depression in older people with multimorbidity: 24-month follow-up of a trial of internet-delivered cognitive behaviour therapy

BACKGROUND

older people coping with the impacts of living with multimorbidity are at increased risk of developing a depressive disorder.

OBJECTIVE

this article reports the 24-month results of a randomised controlled trial of an internet-delivered cognitive behaviour therapy, which aimed to test whether depressive disorders could be prevented in this population.

PARTICIPANTS

community-based participants aged 65 years and over, who had two or more chronic physical health conditions and were assessed as having no current depressive disorder.

METHODS

in total, 302 participants were randomised to an 8-week, five-lesson, internet-delivered intervention program (n = 150) or treatment as usual (TAU, n = 152). The primary outcomes were cases of depressive disorder, assessed post-intervention and at 3-month intervals throughout the trial, and depressive symptoms, assessed at pre-intervention, post-intervention, 6, 12 and 24 months following the intervention.

RESULTS

there were significantly fewer cases of depressive disorder in the intervention group (n = 23, 15%) compared with the TAU group (n = 41, 27%) during the 24 months after the intervention (χ2(1, N = 302) = 6.13, P = 0.013, odds ratio = 0.490 [95% confidence interval: 0.277, 0.867]), representing a 44% reduction in cases of depressive disorder. No differences were found on depressive symptoms at 24-month follow-up. Internet-delivered cognitive behaviour therapy had high engagement and acceptability.

CONCLUSIONS

the results provide support that depressive disorders can be prevented in older people with multimorbidity through participation in internet-delivered cognitive behaviour therapy. With access to internet-delivered interventions in clinical care settings increasing, this has implications for older patient care where multimorbidity is extremely common.

Psychometric properties of the Intolerance of Uncertainty Scale-12 in generalized anxiety disorder: Assessment of factor structure, measurement properties and clinical utility

Intolerance of uncertainty is a psychological vulnerability implicated in the development and maintenance of generalized anxiety disorder (GAD). The Intolerance of Uncertainty Scale-12 (IUS-12) is a widely used measure, however no studies have thoroughly tested the psychometric properties in a clinically diagnosed GAD sample. This study aimed to evaluate the factor structure, measurement properties and clinical utility of the IUS-12 in clinical and non-clinical samples. Participants were screened using the Anxiety Disorders Interview Schedule for DSM-IV to ascertain clinical (n = 136: principal diagnosis of GAD) or non-clinical status (n = 76). Confirmatory factor analysis determined that the bifactor type (two-factor testlet) model demonstrated significantly better fit in comparison to the unidimensional model for the clinical sample. The IUS-12 exhibited limited multidimensionality indicating that only the total score provides meaningful interpretation. The IUS-12 demonstrated good construct validity (with DASS-21, MCQ-30, and PSWQ), good internal consistency, as well as good test-retest reliability over 12-weeks. The IUS-12 demonstrated responsivity to treatment following cognitive behavioral therapy and mindfulness based psychological interventions. Receiver operating characteristic curve analysis indicated an optimal cut-off score of 28 for distinguishing individuals with GAD from non-clinical cases. Overall, the IUS-12 is a valid, reliable and clinically useful instrument for individuals with GAD.

A randomized controlled trial of internet-delivered cognitive behaviour therapy to prevent the development of depressive disorders in older adults with multimorbidity

BACKGROUND

Multimorbidity, which commonly impacts older adults is associated with higher rates of depression. We aimed to investigate whether internet delivered cognitive-behaviour therapy (iCBT) could prevent depressive disorders in older adults with multimorbidity who were not currently depressed.

METHOD

302 primary care and community participants aged 65 years and over, who had multimorbidity but did not meet criteria for a depressive disorder were randomised to an intervention group who received an eight-week, five session iCBT (n = 150) or to a control group (n = 152) who received treatment as usual. Diagnostic interviews were conducted at baseline, and three and six months after the intervention period, where indicated, and the presence of depressive disorder was the primary outcome.

RESULTS

The intention to treat, chi-square analyses indicated there were significantly fewer cases of depressive disorder in the treatment group compared to the control group by six-month follow-up (χ²(1,302) = 5.21, p = .02).

LIMITATIONS

The main limitations of this RCT are a short follow up period and low proportion of participants who developed depressive disorders. Participants were relatively well educated, with a majority having English as their first language.

CONCLUSIONS

These results indicate that depressive disorder was prevented in the first six months following iCBT with three times the number of cases of depressive disorder in the control group compared to the treatment group. Further research is required to determine whether iCBT can be effective for preventing depressive disorder in this population over a longer time period.

Assessing the Clinical Utility of the Eating Beliefs Questionnaire

Abstract. The Eating Beliefs Questionnaire (EBQ) is a valid and reliable self-report tool measuring positive and negative beliefs about binge eating. This study sought to further investigate the clinical utility of the EBQ using a clinical binge eating sample and a healthy control comparison group. Clinical participants were 74 individuals seeking treatment for eating disorders: 38 with bulimia nervosa and 36 with binge eating disorder. Healthy controls were 114 individuals recruited from the general community. Participants all completed a test battery that included the EBQ. Diagnoses of clinical participants were confirmed using the semi-structured interview, the Eating Disorders Examination, administered by a trained clinician. The EBQ and its subscales showed good internal consistency, and significant differences between the clinical and nonclinical groups were observed for EBQ total and subscales scores, but not between the two clinical groups. Receiver operating characteristic (ROC) curve analyses revealed optimal cutoff scores for the EBQ, which demonstrated excellent sensitivity, specificity, and positive and negative predictive values. Results from this study provide further evidence in support of the EBQ’s psychometric properties. Clinical cutoff scores can be used to assess severity of binge eating-related cognitions in both research and clinical settings.

Processes and pathways to binge eating: development of an integrated cognitive and behavioural model of binge eating

BACKGROUND

There are a number of factors commonly believed to be important to the development and maintenance of binge eating that have been identified across multiple models and theories in the psychological literature. In the present study, we sought to develop and test a psychological model for binge eating that incorporated the main variables identified in the literature to drive binge eating behaviour; specifically, core low self-esteem, negative affect, difficulty with emotional regulation, restricted eating and beliefs about eating.

METHODS

Questionnaire data was collected from 760 unselected participants. The proposed model of binge eating was developed, bivariate relationships between the included variables were assessed, and the goodness-of-fit of this new model was evaluated using structural equations modelling.

RESULT

The results identified significant bivariate relationships between all the included variables. While the originally proposed model did not provide a good fit to the data, the revised version of the model provided a good fit to the data.

CONCLUSIONS

Supporting, integrating and building upon the current existing psychological models of binge eating, this study presents a new integrated cognitive and behavioural model of binge eating. The dual-pathway to binge eating identified in the new model provides a different way to understand transdiagnostic binge eating.

Beliefs about Binge Eating: Psychometric Properties of the Eating Beliefs Questionnaire (EBQ-18) in Eating Disorder, Obese, and Community Samples

Binge eating is a core diagnostic feature of bulimia nervosa, binge eating disorder, anorexia nervosa binge/purge type, and is a common feature of "other specified" and "unspecified" feeding and eating disorders. It has been suggested that specific metacognitive beliefs about food, eating, and binge eating may play a key role in the maintenance of binge eating behaviour. The Eating Beliefs Questionnaire (EBQ-18) provides a brief self-report assessment tool measuring three types of metacognitive beliefs: negative, positive, and permissive beliefs about food and eating. This study aimed to build on past research by validating the factor structure and psychometric properties of the EBQ-18 using both a clinical and non-clinical sample. A sample of 688 participants (n = 498 non-clinical participants, n = 161 participants seeking treatment for an eating disorder, and n = 29 participants seeking treatment for obesity) completed a battery of questionnaires, including the EBQ-18 and other measures of eating disorder symptoms and relevant constructs. A subset of 100 non-clinical participants completed the test battery again after an interval of two-weeks, and 38 clinical participants completed the EBQ-18 before and after receiving psychological treatment for their eating disorder. A confirmatory factor analysis (CFA) was conducted and psychometric properties of this measure were assessed. The results of this study provide support for the three-factor model of the EBQ-18. In addition, the EBQ-18 was found to be a valid and reliable measure, with excellent internal consistency, good test-retest reliability in the non-clinical sample, and also demonstrated evidence of sensitivity to treatment in clinical samples with binge eating pathology. Receiver operating characteristic (ROC) curve analyses were used to identify optimal cut-off scores for the EBQ-18. This study provides valuable information about the utility of the EBQ-18 as a measure for use in both clinical and research settings.

Quantitative trait loci associated with soybean seed weight and composition under different phosphorus levels

Seed size and composition are important traits in food crops and can be affected by nutrient availability in the soil. Phosphorus (P) is a non-renewable, essential macronutrient, and P deficiency limits soybean (Glycine max) yield and quality. To investigate the associations of seed traits in low- and high-P environments, soybean recombinant inbred lines (RILs) from a cross of cultivars Fiskeby III and Mandarin (Ottawa) were grown under contrasting P availability environments. Traits including individual seed weight, seed number, and intact mature pod weight were significantly affected by soil P levels and showed transgressive segregation among the RILs. Surprisingly, P treatments did not affect seed composition or weight, suggesting that soybean maintains sufficient P in seeds even in low-P soil. Quantitative trait loci (QTLs) were detected for seed weight, intact pods, seed volume, and seed protein, with five significant QTLs identified in low-P environments and one significant QTL found in the optimal-P environment. Broad-sense heritability estimates were 0.78 (individual seed weight), 0.90 (seed protein), 0.34 (seed oil), and 0.98 (seed number). The QTLs identified under low P point to genetic regions that may be useful to improve soybean performance under limiting P conditions.

The revised short-form of the Eating Beliefs Questionnaire: Measuring positive, negative, and permissive beliefs about binge eating

BACKGROUND

The Eating Beliefs Questionnaire (EBQ) is a self-report assessment tool that measures positive and negative beliefs about food and eating that are believed to play a key role in maintaining binge eating behaviour that occurs in individuals with Bulimia Nervosa, Binge Eating Disorder and other atypical eating disorders. The present study aimed to further refine this measure with the addition of a third scale to assess permissive beliefs about eating, also thought to play a crucial role in the maintenance of binge eating. Permissive beliefs are defined as beliefs about eating that provide justification for the individual to engage in a binge eating episode.

METHODS

After consultation with the literature and endorsement from 10 experts in eating disorders, 19 permissive belief items were generated. Eight hundred eighty-three participants were recruited to complete a test battery online that included the EBQ and the new permissive items.

RESULTS

An exploratory factor analysis (n = 441) found a three-factor solution (positive, negative and permissive beliefs) explaining 63.4% of variance. A confirmatory factor analysis (n = 442) provided support for the three-factor model, with the data best supporting a shorter 18-item questionnaire. The revised scale demonstrated good internal consistency, as well as good convergent validity with measures of related eating disorder symptoms, emotional regulation, mood and anxiety.

CONCLUSIONS

With the addition of a third scale to measure permissive beliefs, the revised short-form of the EBQ offers clinicians and researchers a brief comprehensive tool for the measurement of positive, negative and permissive beliefs about binge eating.

Confirmatory factor analysis and examination of the psychometric properties of the eating beliefs questionnaire

BACKGROUND

The Eating Beliefs Questionnaire (EBQ) is a 27-item self-report measure that assesses positive and negative beliefs about binge eating. It has been validated and its factor structure explored in a non-clinical sample. This study tested the psychometric properties of the EBQ in a clinical and a non-clinical sample.

METHOD

A sample of 769 participants (573 participants recruited from the university and general community, 76 seeking treatment for an eating disorder and 120 participating in obesity research) completed a battery of questionnaires. A subset of clinical participants with a diagnosis of Bulimia Nervosa or Binge Eating Disorder completed the test-battery before and after receiving a psychological treatment (n = 27) or after allocation to a wait-list period (n = 28), and a subset of 35 community participants completed the test battery again after an interval of two-weeks. Confirmatory Factor Analysis (CFA) was performed.

RESULTS

CFA found a two-factor structure that provided a good fit to the data, supporting the solution presented in the development paper. Items with poor psychometric properties were removed, resulting in a 16 item measure. EBQ scores were found to correlate with binge eating episode frequency, increases in body mass index (BMI), and measures of eating disorder behaviours and related psychopathology. The EBQ was found to have excellent internal consistency (α = .94), good test-retest reliability (r = .91) and sensitivity to treatment.

CONCLUSION

These findings indicate that the EBQ is a psychometrically sound and clinically useful measure.

Choosing face: The curse of self in profile image selection

People draw automatic social inferences from photos of unfamiliar faces and these first impressions are associated with important real-world outcomes. Here we examine the effect of selecting online profile images on first impressions. We model the process of profile image selection by asking participants to indicate the likelihood that images of their own face (“self-selection”) and of an unfamiliar face (“other-selection”) would be used as profile images on key social networking sites. Across two large Internet-based studies (n = 610), in line with predictions, image selections accentuated favorable social impressions and these impressions were aligned to the social context of the networking sites. However, contrary to predictions based on people’s general expertise in self-presentation, other-selected images conferred more favorable impressions than self-selected images. We conclude that people make suboptimal choices when selecting their own profile pictures, such that self-perception places important limits on facial first impressions formed by others. These results underscore the dynamic nature of person perception in real-world contexts.

Phenotypic variation and identification of quantitative trait loci for ozone tolerance in a Fiskeby III × Mandarin (Ottawa) soybean population

KEY MESSAGE

Soybean quantitative trait loci for ozone response. Ground-level ozone reduces yield in crops such as soybean (Glycine max (L.) Merr.). Phenotypic variation has been observed for this trait in multiple species; however, breeding for ozone tolerance has been limited. A recombinant inbred population was developed from soybean genotypes differing in tolerance to ozone: tolerant Fiskeby III and sensitive Mandarin (Ottawa). Plants were exposed to ozone treatment for 5 days in greenhouse chambers followed by visual scoring for foliar injury. Mean injury score in the mid-canopy was 16 % for Fiskeby III, and 81 % for Mandarin (Ottawa). Injury scores were lower in younger leaves for both parents and progeny, compared to scores in the older leaves. Segregation was consistent with multigenic inheritance. Correlation coefficients for injury between leaf positions ranged from 0.34 to 0.81, with the closer leaf positions showing the greater correlation. Narrow sense heritability within an ozone treatment chamber was 0.59, 0.40, 0.29, 0.30, 0.19, and 0.35 for the 2nd, 3rd, 4th, 5th, 6th, and combined 3rd-5th main stem leaf positions (numbered acropetally), respectively, based on genotypic means over three independent replications. Quantitative trait loci (QTL) analysis showed that loci were associated with distinct leaf developmental stages. QTL were identified on Chromosome 17 for the 2nd and 3rd leaf positions, and on Chromosome 4 for the 5th and 6th leaf positions. Additional loci were identified on Chromosomes 6, 18, 19, and 20. Interacting loci were identified on Chromosomes 5 and 15 for injury on trifoliate 4. The ozone sensitive parent contributed one favorable allele for ozone response.

Psychometric evaluation of self-report measures of binge-eating symptoms and related psychopathology: A systematic review of the literature

OBJECTIVE

Binge eating is a symptom common to bulimia nervosa, anorexia nervosa (binge/purge subtype), and binge eating disorder. There are many self-report measures available to aid the assessment of eating disorders symptoms, but there has not yet been a systematic review of the literature to identify the most valid and reliable measures for use in assessment and treatment of binge eating.

METHOD

A systematic review of the psychometric properties of self-report measures that assess binge eating symptoms and psychopathology was conducted. Two independent raters assessed the psychometric properties of each measure using a standardized quality analysis tool.

RESULTS

Of the 2,927 studies identified, 72 studies met the inclusion criteria and described the psychometric properties of 29 different self-report measures, and nine specific subscales within these. Results from the quality analysis tool utilized in this study indicated that none of the included measures currently meet all nine criteria of adequate psychometric properties.

DISCUSSION

Most of the included measures had evidence for some adequate psychometric properties. Two measures received six out of nine positive ratings for the assessed psychometric properties, the BITE and the BULIT-R, and thus appear to be the measures with the most evidence of their validity and reliability. Overall, our findings implicate a need for further investigation of the psychometric properties of the available self-report questionnaires in this field.

Not looking yourself: The cost of self-selecting photographs for identity verification

Photo-identification is based on the premise that photographs are representative of facial appearance. However, previous studies show that ratings of likeness vary across different photographs of the same face, suggesting that some images capture identity better than others. Two experiments were designed to examine the relationship between likeness judgments and face matching accuracy. In Experiment 1, we compared unfamiliar face matching accuracy for self-selected and other-selected high-likeness images. Surprisingly, images selected by previously unfamiliar viewers - after very limited exposure to a target face - were more accurately matched than self-selected images chosen by the target identity themselves. Results also revealed extremely low inter-rater agreement in ratings of likeness across participants, suggesting that perceptions of image resemblance are inherently unstable. In Experiment 2, we test whether the cost of self-selection can be explained by this general disagreement in likeness judgments between individual raters. We find that averaging across rankings by multiple raters produces image selections that provide superior identification accuracy. However, benefit of other-selection persisted for single raters, suggesting that inaccurate representations of self interfere with our ability to judge which images faithfully represent our current appearance.

QTL mapping and phenotypic variation of root anatomical traits in maize (Zea mays L.)

Root anatomical trait variation is described for three maize RIL populations. Six quantitative trait loci (QTL) are presented for anatomical traits: root cross-sectional area, % living cortical area, aerenchyma area, and stele area. Root anatomy is directly related to plant performance, influencing resource acquisition and transport, the metabolic cost of growth, and the mechanical strength of the root system. Ten root anatomical traits were measured in greenhouse-grown plants from three recombinant inbred populations of maize [intermated B73 × Mo17 (IBM), Oh43 × W64a (OhW), and Ny821 × H99 (NyH)]. Traits included areas of cross section, stele, cortex, aerenchyma, and cortical cells, percentages of the cortex occupied by aerenchyma, and cortical cell file number. Significant phenotypic variation was observed for each of the traits, with maximum values typically seven to ten times greater than minimum values. Means and ranges were similar for the OhW and NyH populations for all traits, while the IBM population had lower mean values for the majority of traits, but a 50% greater range of variation for aerenchyma area. A principal component analysis showed a similar trait structure for the three families, with clustering of area and count traits. Strong correlations were observed among area traits in the cortex, stele, and cross-section. The aerenchyma and percent living cortical area traits were independent of other traits. Six QTL were identified for four of the traits. The phenotypic variation explained by the QTL ranged from 4.7% (root cross-sectional area, OhW population) to 12.0% (percent living cortical area, IBM population). Genetic variation for root anatomical traits can be harnessed to increase abiotic stress tolerance and provide insights into mechanisms controlling phenotypic variation for root anatomy.

QTL mapping and phenotypic variation for root architectural traits in maize (Zea mays L.)

QTL were identified for root architectural traits in maize. Root architectural traits, including the number, length, orientation, and branching of the principal root classes, influence plant function by determining the spatial and temporal domains of soil exploration. To characterize phenotypic patterns and their genetic control, three recombinant inbred populations of maize were grown for 28 days in solid media in a greenhouse and evaluated for 21 root architectural traits, including length, number, diameter, and branching of seminal, primary and nodal roots, dry weight of embryonic and nodal systems, and diameter of the nodal root system. Significant phenotypic variation was observed for all traits. Strong correlations were observed among traits in the same root class, particularly for the length of the main root axis and the length of lateral roots. In a principal component analysis, relationships among traits differed slightly for the three families, though vectors grouped together for traits within a given root class, indicating opportunities for more efficient phenotyping. Allometric analysis showed that trajectories of growth for specific traits differ in the three populations. In total, 15 quantitative trait loci (QTL) were identified. QTL are reported for length in multiple root classes, diameter and number of seminal roots, and dry weight of the embryonic and nodal root systems. Phenotypic variation explained by individual QTL ranged from 0.44% (number of seminal roots, NyH population) to 13.5% (shoot dry weight, OhW population). Identification of QTL for root architectural traits may be useful for developing genotypes that are better suited to specific soil environments.

Evaluation of motor vehicle driving performance in patients with chronic diplopia

BACKGROUND

Uncorrected diplopia is a condition that may make it unsafe for a person to operate a motor vehicle. In some jurisdictions, physicians are required by law to report the person with diplopia to the appropriate authority.

METHODS

In this masked study, 10 patients of varying ages with stable diplopia of greater than 6 months' duration and 10 age-matched control subjects were placed in a driving simulator and evaluated on their performance. Various cues and threats, including near-accident situations, were presented; stimulus recognition and reaction times were recorded.

RESULTS

No significant difference was found between the groups for either cue or threat recognition responses or reaction times. Increasing age was the factor most associated with poor response performance on all test measures (P < .001). Slowed response time in patients with poor binocular single vision was the only other significant association.

CONCLUSION

Although response times were slower in subjects with poor binocular single vision scores, stimulus recognition responses were not significantly different; in our opinion, stimulus recognition is more relevant to driving performance and therefore chronic diplopia does not appear to be a contraindication for driving a motor vehicle.

So great a cloud of witnesses: the use of family systems process in forming pastoral identity and facilitating pastoral functioning

Describes the use of genograms in units of Clinical Pastoral Education. Provides the reader with a theoretical base for viewing experiences in CPE as manifestations of family of origin factors. Reflects on how such connections can enrich recognitions of the power of transference in relationships and thus provide the caregiver with greater insight into how he or she may express ministry and caregiving activities.

Carrier detection in Sandhoff disease

Three new cases of Sandhoff disease are reported. One infant was the second affected child in a large family. The parents, who were cousins, were part of a large kindred from an isolated community in northern Saskatchewan. We assayed total and heat-stable hexosaminidases in 38 other members of the kindred and found two distinct cohorts. Sixteen individuals had low total and low heat-stable hexosaminidase and were diagnosed as carriers of Sandhoff disease. The values for the remainder were within normal limits. In a retrospective study of data from more than 14,000 Ashkenazi Jews, who were screened for Tay-Sachs disease, six were identified as Sandhoff carriers. Our data indicate that carrier detection requires measurement of both total and heat-stable enzyme activity.