The clinical assessment of systemic hypertension in optometric practice

This thesis sets out to examine in detail the condition of systemic hypertension (high Blood Pressure) in relation to optometric practice in the United Kingdom. Systemic hypertension, which is asymptomatic in the early stages, is diagnosed from the Blood Pressure (BP) measurement recorded by a sphygmomanometer and/or from the complications that have developed in target organs. Optometric practice based surveys revealed that diagnosed systemic hypertension was the most prevalent cardiovascular medical condition (20.5%). Measurement of BP of patients in this sample revealed that if an optometrist included sphygmomanometry into the sight examination then at least one patient each day would be referred for suspect systemic hypertension. Optometric opinion felt that the measurement of BP in optometric practice would advance the profession, being appreciated by both patients and General Practitioners (GPs), but was felt to be an unnecessary routine procedure. The present sight examination for the systemic hypertensive is similar to that of the normotensive patient, but may involve an altered fundus examination and a visual field test. The GPs were in favour of optometric BP measurement and a future role in the share care management of the systemic hypertensive. The application of a new pictorial grading scale for the grading of vascular changes associated with pre-malignant systemic hypertension was found to be both accurate and reliable. Clinical trial of the grading scale in optometric practice found positive correlations between BP and increasing severity of the retinal vascular features. The subtle pre-malignant vascular changes require reliable accurate detection and analysis to assist in the management of the systemic hypertensive patient. Vessel width was shown to decrease with increasing age. Image analysis of the A/V ratio, arteriolar tortuosity and focal calibre changes revealed a positive correlation to the patient's BP (p<0.001). The retinal vasculature is relatively stable longitudinally with only minor changes in response to early disease states. Age and elevated BP increased a patient's risk of developing systemic medical conditions over a two-year period. The application of the pictorial grading scale to optometric practice and training the optometrist in the use of sphygmomanometry would improve the management of the systemic hypertensive patient in optometric practice. Future advances in image analysis hold substantial benefits for the detection and monitoring of subtle vascular changes associated with systemic hypertension.

Functional near vision assessment in presbyopia

The aim of this thesis was to develop standards of best practice for the subjective assessment of near visual function in presbyopia. Near visual acuity (VA) is a quick and simple measure but an assessment of the maximum reading speed and the smallest print size that can maintain this are equally important, to gain a better reflection of real world visual function. These metrics are dependent on the amplitude of accommodation (AoA) and often this must be evaluated using subjective techniques. Defocus curves are less susceptible than the push-up/push-down test to the influence of blur tolerance but their implementation must be standardised such that letter sequences and the order of lens presentation are randomised, to avoid memory effects, whilst the AoA should be quantified as the range of defocus for which only the best VA is maintained. In addition to such clinical assessments, subjective questionnaire evaluations are also important, to determine whether at least an individual’s needs are met. The Near Activity Visual Questionnaire (NAVQ) developed in this thesis can be used for this. Using these standardised near vision metrics it is shown that visual performance with monovision and multifocal contact lenses is comparable whilst initial outcomes of single optic ‘accommodating’ intraocular lens implantation are unlikely to be sustained in the long-term.

Assessment of time frequency warping for use as a reference degradation for assessing synthetic speech

At present there is no standard assessment method for rating and comparing the quality of synthesized speech. This study assesses the suitability of Time Frequency Warping (TFW) modulation for use as a reference device for assessing synthesized speech. Time Frequency Warping modulation introduces timing errors into natural speech that produce perceptual errors similar to those found in synthetic speech. It is proposed that TFW modulation used in conjunction with a listening effort test would provide a standard assessment method for rating the quality of synthesized speech. This study identifies the most suitable TFW modulation variable parameter to be used for assessing synthetic speech and assess the results of several assessment tests that rate examples of synthesized speech in terms of the TFW variable parameter and listening effort. The study also attempts to identify the attributes of speech that differentiate synthetic, TFW modulated and natural speech.

Rapid testing for group B streptococcus during labour: a test accuracy study with evaluation of acceptability and cost-effectiveness

OBJECTIVE: To determine the accuracy, acceptability and cost-effectiveness of polymerase chain reaction (PCR) and optical immunoassay (OIA) rapid tests for maternal group B streptococcal (GBS) colonisation at labour. DESIGN: A test accuracy study was used to determine the accuracy of rapid tests for GBS colonisation of women in labour. Acceptability of testing to participants was evaluated through a questionnaire administered after delivery, and acceptability to staff through focus groups. A decision-analytic model was constructed to assess the cost-effectiveness of various screening strategies. SETTING: Two large obstetric units in the UK. PARTICIPANTS: Women booked for delivery at the participating units other than those electing for a Caesarean delivery. INTERVENTIONS: Vaginal and rectal swabs were obtained at the onset of labour and the results of vaginal and rectal PCR and OIA (index) tests were compared with the reference standard of enriched culture of combined vaginal and rectal swabs. MAIN OUTCOME MEASURES: The accuracy of the index tests, the relative accuracies of tests on vaginal and rectal swabs and whether test accuracy varied according to the presence or absence of maternal risk factors. RESULTS: PCR was significantly more accurate than OIA for the detection of maternal GBS colonisation. Combined vaginal or rectal swab index tests were more sensitive than either test considered individually [combined swab sensitivity for PCR 84% (95% CI 79-88%); vaginal swab 58% (52-64%); rectal swab 71% (66-76%)]. The highest sensitivity for PCR came at the cost of lower specificity [combined specificity 87% (95% CI 85-89%); vaginal swab 92% (90-94%); rectal swab 92% (90-93%)]. The sensitivity and specificity of rapid tests varied according to the presence or absence of maternal risk factors, but not consistently. PCR results were determinants of neonatal GBS colonisation, but maternal risk factors were not. Overall levels of acceptability for rapid testing amongst participants were high. Vaginal swabs were more acceptable than rectal swabs. South Asian women were least likely to have participated in the study and were less happy with the sampling procedure and with the prospect of rapid testing as part of routine care. Midwives were generally positive towards rapid testing but had concerns that it might lead to overtreatment and unnecessary interference in births. Modelling analysis revealed that the most cost-effective strategy was to provide routine intravenous antibiotic prophylaxis (IAP) to all women without screening. Removing this strategy, which is unlikely to be acceptable to most women and midwives, resulted in screening, based on a culture test at 35-37 weeks' gestation, with the provision of antibiotics to all women who screened positive being most cost-effective, assuming that all women in premature labour would receive IAP. The results were sensitive to very small increases in costs and changes in other assumptions. Screening using a rapid test was not cost-effective based on its current sensitivity, specificity and cost. CONCLUSIONS: Neither rapid test was sufficiently accurate to recommend it for routine use in clinical practice. IAP directed by screening with enriched culture at 35-37 weeks' gestation is likely to be the most acceptable cost-effective strategy, although it is premature to suggest the implementation of this strategy at present.

Pulse oximetry as a screening test for congenital heart defects in newborn infants: a test accuracy study with evaluation of acceptability and cost-effectiveness

Background: Screening for congenital heart defects (CHDs) relies on antenatal ultrasound and postnatal clinical examination; however, life-threatening defects often go undetected. Objective: To determine the accuracy, acceptability and cost-effectiveness of pulse oximetry as a screening test for CHDs in newborn infants. Design: A test accuracy study determined the accuracy of pulse oximetry. Acceptability of testing to parents was evaluated through a questionnaire, and to staff through focus groups. A decision-analytic model was constructed to assess cost-effectiveness. Setting: Six UK maternity units. Participants: These were 20,055 asymptomatic newborns at = 35 weeks’ gestation, their mothers and health-care staff. Interventions: Pulse oximetry was performed prior to discharge from hospital and the results of this index test were compared with a composite reference standard (echocardiography, clinical follow-up and follow-up through interrogation of clinical databases). Main outcome measures: Detection of major CHDs – defined as causing death or requiring invasive intervention up to 12 months of age (subdivided into critical CHDs causing death or intervention before 28 days, and serious CHDs causing death or intervention between 1 and 12 months of age); acceptability of testing to parents and staff; and the cost-effectiveness in terms of cost per timely diagnosis. Results: Fifty-three of the 20,055 babies screened had a major CHD (24 critical and 29 serious), a prevalence of 2.6 per 1000 live births. Pulse oximetry had a sensitivity of 75.0% [95% confidence interval (CI) 53.3% to 90.2%] for critical cases and 49.1% (95% CI 35.1% to 63.2%) for all major CHDs. When 23 cases were excluded, in which a CHD was already suspected following antenatal ultrasound, pulse oximetry had a sensitivity of 58.3% (95% CI 27.7% to 84.8%) for critical cases (12 babies) and 28.6% (95% CI 14.6% to 46.3%) for all major CHDs (35 babies). False-positive (FP) results occurred in 1 in 119 babies (0.84%) without major CHDs (specificity 99.2%, 95% CI 99.0% to 99.3%). However, of the 169 FPs, there were six cases of significant but not major CHDs and 40 cases of respiratory or infective illness requiring medical intervention. The prevalence of major CHDs in babies with normal pulse oximetry was 1.4 (95% CI 0.9 to 2.0) per 1000 live births, as 27 babies with major CHDs (6 critical and 21 serious) were missed. Parent and staff participants were predominantly satisfied with screening, perceiving it as an important test to detect ill babies. There was no evidence that mothers given FP results were more anxious after participating than those given true-negative results, although they were less satisfied with the test. White British/Irish mothers were more likely to participate in the study, and were less anxious and more satisfied than those of other ethnicities. The incremental cost-effectiveness ratio of pulse oximetry plus clinical examination compared with examination alone is approximately £24,900 per timely diagnosis in a population in which antenatal screening for CHDs already exists. Conclusions: Pulse oximetry is a simple, safe, feasible test that is acceptable to parents and staff and adds value to existing screening. It is likely to identify cases of critical CHDs that would otherwise go undetected. It is also likely to be cost-effective given current acceptable thresholds. The detection of other pathologies, such as significant CHDs and respiratory and infective illnesses, is an additional advantage. Other pulse oximetry techniques, such as perfusion index, may enhance detection of aortic obstructive lesions.

An assessment of web-based textbook supplementary material to support student learning

There is an increasing trend by publishers to provide supplementary learning materials with text books in order to improve the learning experience and thus ultimately improve text book sales. This study will aim to establish the use of these materials and their relevance to students in terms of supporting student learning. The materials include multiple choice test banks, animated demonstrations, simulations, quizzes and electronic versions of the text. The study will focus on the extensive library of web-based learning materials available on the ‘WileyPlus’ web platform which accompanies the textbook ‘Operations Management’, 2nd edition authored by A. Greasley and published by John Wiley and Sons Ltd.

Can computer-based testing achieve quality and efficiency in assessment?

This paper reports findings of a two year study concerning the development and implementation of a general-purpose computer-based assessment (CBA) system at a UK University. Data gathering took place over a period of nineteen months, involving a number of formative and summative assessments. Approximately 1,000 students, drawn from undergraduate courses, were involved in the exercise. The techniques used in gathering data included questionnaires, observation, interviews and an analysis of student scores in both conventional examinations and computer-based assessments. Comparisons with conventional assessment methods suggest that the use of CBA techniques may improve the overall performance of students. However it is clear that the technique must not be seen as a "quick fix" for problems such as rising student numbers. If one accepts that current systems test only a relatively narrow range of skills, then the hasty implementation of CBA systems will result in a distorted and inaccurate view of student performance. In turn, this may serve to reduce the overall quality of courses and - ultimately - detract from the student learning experience. On the other hand, if one adopts a considered and methodical approach to computer-based assessment, positive benefits might include increased efficiency and quality, leading to improved student learning.

Mobile app Aston contrast sensitivity test

BACKGROUND: Contrast detection is an important aspect of the assessment of visual function; however, clinical tests evaluate limited spatial frequencies and contrasts. This study validates the accuracy and inter-test repeatability of a swept-frequency near and distance mobile app Aston contrast sensitivity test, which overcomes this limitation compared to traditional charts. METHOD: Twenty subjects wearing their full refractive correction underwent contrast sensitivity testing on the new near application (near app), distance app, CSV-1000 and Pelli-Robson charts with full correction and with vision degraded by 0.8 and 0.2 Bangerter degradation foils. In addition repeated measures using the 0.8 occluding foil were taken. RESULTS: The mobile apps (near more than distance, p = 0.005) recorded a higher contrast sensitivity than printed tests (p < 0.001); however, all charts showed a reduction in measured contrast sensitivity with degradation (p < 0.001) and a similar decrease with increasing spatial frequency (interaction > 0.05). Although the coefficient of repeatability was lowest for the Pelli-Robson charts (0.14 log units), the mobile app charts measured more spatial frequencies, took less time and were more repeatable (near: 0.26 to 0.37 log units; distance: 0.34 to 0.39 log units) than the CSV-1000 (0.30 to 0.93 log units). The duration to complete the CSV-1000 was 124 ± 37 seconds, Pelli-Robson 78 ± 27 seconds, near app 53 ± 15 seconds and distance app 107 ± 36 seconds. CONCLUSIONS: While there were differences between charts in contrast levels measured, the new Aston near and distance apps are valid, repeatable and time-efficient method of assessing contrast sensitivity at multiple spatial frequencies.

Automatized Generation of Metadata and Calibrated Test Item Banks for E-learning

Report published in the Proceedings of the National Conference on "Education in the Information Society", Plovdiv, May, 2013

Congenital prosopagnosia in a child:neuropsychological assessment, eye movement recordings and training

Here we report the assessment and treatment of a 6-year-old boy (L.G.) who was referred to us for congenital prosopagnosia (CP). We investigated his performance using a test battery and eye movement recordings pre- and post-training. L.G. showed deficits in recognising relatives and learning new faces, and misrecognition of unfamiliar people. Eye movement recordings showed that L.G. focused on the lower part of stimuli in naming tasks based on familiar or unfamiliar incomplete or complete faces. The training focused on improving his ability to explore internal features of faces, to discriminate specific facial features of familiar and unfamiliar faces, and to provide his family with strategies to use in the future. At the end of the training programme L.G. no longer failed to recognise close and distant relatives and classmates and did not falsely recognise unknown people.

Signal processing of physiological signals for automated assessment of stress in computer users

The need to provide computers with the ability to distinguish the affective state of their users is a major requirement for the practical implementation of affective computing concepts. This dissertation proposes the application of signal processing methods on physiological signals to extract from them features that can be processed by learning pattern recognition systems to provide cues about a person's affective state. In particular, combining physiological information sensed from a user's left hand in a non-invasive way with the pupil diameter information from an eye-tracking system may provide a computer with an awareness of its user's affective responses in the course of human-computer interactions. In this study an integrated hardware-software setup was developed to achieve automatic assessment of the affective status of a computer user. A computer-based "Paced Stroop Test" was designed as a stimulus to elicit emotional stress in the subject during the experiment. Four signals: the Galvanic Skin Response (GSR), the Blood Volume Pulse (BVP), the Skin Temperature (ST) and the Pupil Diameter (PD), were monitored and analyzed to differentiate affective states in the user. Several signal processing techniques were applied on the collected signals to extract their most relevant features. These features were analyzed with learning classification systems, to accomplish the affective state identification. Three learning algorithms: Naïve Bayes, Decision Tree and Support Vector Machine were applied to this identification process and their levels of classification accuracy were compared. The results achieved indicate that the physiological signals monitored do, in fact, have a strong correlation with the changes in the emotional states of the experimental subjects. These results also revealed that the inclusion of pupil diameter information significantly improved the performance of the emotion recognition system. ^

A comprehensive assessment of self -report experiences of adoptive parents of special needs children in Florida

Adoption of special needs children is now seen as a life long event whereby the adoptive child and family have unique needs. The need for postplacement resources throughout the life cycle of the adoption process is evident. This exploratory-descriptive research employed a random stratified cross-sectional design. The purpose of the study was to describe, identify, examine, and assess the relative influence of identified empirically and conceptually relevant variables of self-report experiences of adoptive parents of special needs children. Primary areas of exploration included: (1) adoptive children and families' characteristics, (2) postplacement service needs, utilization and satisfaction, and (3) adoptive parents' perceptions of their adoption experiences. A proportionate stratified random mail survey was used to obtain 474 families who had adopted special needs children from the 15 geographic districts which make up the state adoption social service agency in Florida. A 144-item survey questionnaire was used to collect basic information on demographic data, service provision, and adoption experiences. Four research questions were analyzed to test the effect the predictor variables had on willingness to adopt another special needs child, successful adoption, satisfying experience, and realism about problems. All four research questions revealed that the full model and the child's antecedent and the adoptive parents' intervening variable blocks were significant in explaining the variance in the dependent variables. The child's intervening variables alone were only significant in explaining the variance for one of the dependent variables. The results of the statistical analysis on the fifth research question and the three hypotheses determined that (1) only one postplacement service, crisis intervention, had a statistically significant impact on the adoptive parents' perceived level of satisfaction with the adoption experience; (2) adoptive parents who rate their adoption as successful are more likely to express a desire to adopt another special needs child; (3) the more adequate information on the child the adoptive parents perceived that they had prior to placement, the more they perceived they were realistic about the problems they would encounter; and (4) six specific postplacement services were found to be significant in predicting successful adoptions--crisis intervention, outpatient drug/alcohol treatment, maintenance subsidy, physical therapy, special medical equipment, and family counseling. Implications for the social work field and future research are discussed. ^

The therapeutic effects of Millon Clinical Multiaxial Inventory -III assessment feedback

A study was conducted to test the therapeutic effects of assessment feedback on rapport-building and self-enhancement variables (self-verification, self-discovery, self-esteem), as well as symptomatology. Assessment feedback was provided in the form of interpretive information based on the results of the Millon Clinical Multiaxial Inventory-III (MCMI-III). Participants (N = 89) were randomly assigned to three groups: a Feedback group, a Reflective-Counseling group, and a No-Feedback group. The Feedback group was provided with assessment feedback, the Reflective-Counseling group was asked to comment on the meaning of the taking the MCMI-III, the No-Feedback group received general information about the MCMI-III. Results revealed that assessment feedback, when provided in the form of interpretive interpretation positively affects rapport-building and self-enhancement variables (self-verification and self-discovery). No significant results were found in terms of self-esteem or symptom decrease as a function of feedback. However, a significant decrease in symptoms across groups was found. Results indicate that assessment feedback in the form of interpretive information can be used as a starting point in therapy. Implications of the findings are discussed with respect to theory and clinical practice. ^

The effects of school mobility in pre -assessment grade levels on student performance and school accountability in urban Title I schools

This study examined the effects of student mobility and educational enrollment experiences on academic achievement. The educational progress, school enrollments and transfers of inner-city elementary students were tracked over a four-year period. Student achievement was measured by criterion-referenced reading tests administered in the second semester of the third grade. It further analyzed the degree to which the switch to different basal reading textbooks interrupted the continuity of education thereby contributing to the detrimental effects of intra-district mobility. ^ Mobility histories of 2,913 third grade students were collected to evaluate the number of times each student entered or withdrew from a Miami-Dade County Public School beginning in August 2000 through March 2004, and distinguished between transfers that occurred during the academic school year and those that occurred during summer months. Data were analyzed using Pearson correlations and multiple regressions to determine if school mobility contributed to performance on the Florida Comprehensive Assessment Third Grade Reading Test (FCAT). Transferring from one school to another was found to have a significant negative impact on student test scores. Transfers within the academic school year were more detrimental than transfers that occurred during the summer months. Third grade students who transferred into schools that used the same reading textbook series were found to have significantly higher FCAT reading scores than third graders who transferred into schools that used different reading textbooks. ^ The effects of mobility rates on overall school performance were also examined. Data was collected on 124 Title I elementary schools to determine the degree to which mobility affected school accountability scores. Title I schools with high student mobility rates had significantly lower accountability scores than schools with lower student mobility rates. ^ The results of this study highlight the impact of education and housing policy and imply a need for programs and practices that promote stability in the early elementary years. ^

Application and evaluation of an Institute of Medicine approach to dietary assessment and planning in long -term care

The primary purpose of these studies was to determine the effect of planning menus using the Institute of Medicine's (IOMs) Simple Nutrient Density Approach on nutrient intakes of long-term care (LTC) residents. In the first study, nutrient intakes of 72 subjects were assessed using Dietary Reference Intakes (DRIs) and IOM methodology. The intake distributions were used to set intake and menu planning goals. In the second study, the facility's regular menus were modified to meet the intake goals for vitamin E, magnesium, zinc, vitamin D and calcium. An experiment was used to test whether the modified menu resulted in intakes of micronutrients sufficient to achieve a low prevalence (<3%) of nutrient inadequacies. Three-day weighed food intakes for 35 females were adjusted for day-to-day variations in order to obtain an estimate of long-term average intake and to estimate the proportion of residents with inadequate nutrient intakes. ^ In the first study, the prevalence of inadequate intakes was determined to be between 65-99% for magnesium, vitamin E, and zinc. Mean usual intakes of Vitamin D and calcium were far below the Adequate Intakes (AIs). In the experimental study, the prevalence of inadequacies was reduced to <3% for zinc and vitamin E but not magnesium. The groups' mean usual intake from the modified menu met or exceeded the AI for calcium but fell short for vitamin D. Alternatively, it was determined that addition of a multivitamin and mineral (MVM) supplement to intakes of the regular menu could be used to achieve goals for vitamin E, zinc and vitamin D but not calcium and magnesium. ^ A combination of menu modification and MVM supplementation may be necessary to achieve a low prevalence of micronutrient inadequacies among LTC residents. Menus should be planned to optimize intakes of those nutrients that are low in an MVM, such as calcium, magnesium, and potassium. A MVM supplement should be provided to fill the gap for nutrients not provided in sufficient amounts by the diet, such as vitamin E and vitamin D. ^