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PubMed2005

Management of dental trauma in primary care: a postal survey of general dental practitioners.

OBJECTIVES: To determine the self-perceived knowledge and attitudes of general dental practitioners (GDPs) concerning management of dental trauma in primary care. To identify potential barriers to the management of dental trauma in primary care. DESIGN AND SETTING: A self-completion postal questionnaire survey of 417 GDPs in six local health authority districts in northeast England. MAIN OUTCOME MEASURES: Likert scale responses to 20 statements designed to test self-perceived knowledge and attitudes. Following descriptive statistical analysis. Factor analysis with principle components analysis was undertaken to identify areas of correlation in questionnaire responses, followed by Chi squared test, Spearman's Rank Correlation and analysis of variance (ANOVA) to measure association between variables. RESULTS: The response rate was 74%. Enamel and dentine fractures were the most common injury, with 45% of GDPs responding seeing more than 10 cases of dental trauma in the preceding year and 53% of respondents seeing one to three cases of complicated crown fracture. Seventy-eight per cent believed that NHS remuneration was inadequate, but only 8% would refer patients with dental trauma to secondary care for this reason. Half of the GDPs believed that trauma could be treated more effectively in practice if NHS payments were greater. GDPs were significantly more likely to agree with this statement if they had previously undertaken a postgraduate course in the treatment of dental trauma (p=0.002). Single handed GDPs were statistically significantly more likely to agree with the statements 'I would not treat dental trauma cases at my practice because the NHS payment is inadequate' (p=0.008) and 'Treating dental trauma at my practice requires too much of my clinical time to be worthwhile' (p=0.002). Ninety-six per cent of GDPs disagreed that treatment of dental trauma rested solely within secondary care. Ninety-six per cent of GDPs agreed that they had a responsibility to provide initial emergency treatment for trauma patients prior to referral. Eighty-eight per cent of GDPs felt that aids to management would be useful. CONCLUSIONS: Although GDPs believed that financial remuneration was inadequate, this did not prevent them treating trauma cases. They strongly agreed that they had responsibility for the management of dental trauma in primary care and that they believed trauma could be treated more effectively in practice if payment was greater. Time constraints were perceived as a barrier to long-term management of complex trauma cases in primary care. GDPs would welcome the use of management aids.

Analysis of Variance↗

PubMed2006

Prednisone-induced osteoporosis: an overlooked and undertreated adverse effect.

CONTEXT: Glucocorticoids are used for a variety of medical conditions. This class of drugs is arguably the most common cause of iatrogenic osteoporosis, but studies have shown that physicians are not investigating and treating glucocorticoid-induced osteoporosis. OBJECTIVE: To determine whether primary care physicians (osteopathic and allopathic) are evaluating and treating adult patients at risk for osteoporosis secondary to long-term prednisone use. METHODS: Electronic medical records from three primary care practices (family medicine, geriatric medicine, and internal medicine) were retrospectively reviewed to identify patients who were taking at least 2.5 mg of prednisone per day for 8 weeks or longer. Records were then grouped according to whether patients had undergone bone mineral density screening and had been given therapy to prevent or treat bone loss. Whether patients had comorbid risk factors for secondary osteoporosis (according to the National Institutes of Health Consensus Development Conference Statement on Osteoporosis) was noted to determine whether treatment was given because of prednisone use or because of the comorbid risk factors. Statistical analysis was performed using a Pearson product moment correlation 2-tailed chi2 test. RESULTS: The medical records of 49 patients met inclusion criteria (19 men, 30 women; mean age, 61 years; age range, 21-89 years). A statistically significant difference was found in physician evaluation practices for patients with vs patients without comorbid risk factors (82.1% vs 38.1%; P=.002). CONCLUSION: Primary care physicians do not routinely evaluate patients for osteoporosis secondary to glucocorticoid treatment, especially when patients do not have comorbid risk factors for osteoporosis.

Adult↗

PubMed2003

Analysis of protein structures reveals regions of rare backbone conformation at functional sites.

Regions of rare conformation were located in 300 protein crystal structures representing seven major protein folds. A distance matrix algorithm was used to search rapidly for 9-residue fragments of rare backbone conformation using a comparison to a relational database of encoded fragments derived from the database of nonredundant structures. Rare fragments were found in 61% of the analyzed protein structures. Detailed analysis was performed for 78 proteins of different folds. The rare fragments were located near functional sites in 72% of the protein structures. The rare fragments often formed parts of ligand-binding sites (59%), protein-protein interfaces (8%), and domain-domain contacts (5%). Of the remaining structures, 5% had a high average B-factor or high local B-factors. Statistical analysis suggests that the association between ligands and rare regions does not occur by chance alone. The present study is likely to underestimate the number of functional sites, because not all analyzed protein structures contained a ligand. The results suggest that rapid searches for regions with rare local backbone conformations can assist in prediction of functional sites in novel proteins.

Algorithms↗

PubMed2006

Knowledge of stroke among stroke patients and their relatives in Northwest India.

BACKGROUND: The knowledge of warning symptoms and risk factors for stroke has not been studied among patients with stroke in developing countries. AIMS: We aimed to assess the knowledge of stroke among patients with stroke and their relatives. SETTINGS AND DESIGN: Prospective tertiary referral hospital-based study in Northwest India. MATERIALS AND METHODS: Trained nurses and medical interns interviewed patients with stroke and transient ischemic attack and their relatives about their knowledge of stroke symptoms and risk factors. STATISTICAL ANALYSIS: Univariable and multivariable logistic regression were used. RESULTS: Of the 147 subjects interviewed, 102 (69%) were patients and 45 (31%) were relatives. There were 99 (67%) men and 48 (33%) women and the mean age was 59.7+/-14.1 years. Sixty-two percent of respondents recognized paralysis of one side as a warning symptom and 54% recognized hypertension as a risk factor for stroke. In the multivariable logistic regression analysis, higher education was associated with the knowledge of correct organ involvement in stroke (OR 2.6, CI 1.1- 6.1, P =0.02), whereas younger age (OR 2.7, CI 1.1-7.0, P =0.04) and higher education (OR 4.1, CI 1.5-10.9, P =0.005) correlated with a better knowledge regarding warning symptoms of stroke. CONCLUSIONS: In this study cohort, in general, there is lack of awareness of major warning symptoms, risk factors, organ involvement and self-recognition of stroke. However younger age and education status were associated with better knowledge. There is an urgent need for awareness programs about stroke in this study cohort.

Adult↗

PubMed1999

MRI of growth hormone-secreting pituitary adenomas: factors determining pretreatment hormone levels.

Preoperative serum growth hormone (GH) level is one of the most important determinants of outcome. Our aim was to assess MRI findings which may correlate with pretreatment GH levels in GH-secreting adenomas. We retrospectively studied 29 patients with acromegaly caused by a pituitary adenoma. Tumor size (height, width, thickness and volume), suprasellar extension, sphenoid or cavernous sinus invasion, signal intensity and contrast enhancement were studied. Linear regression analysis or Fisher's exact probability test was used for statistical analysis. Factors related to high GH levels were the maximum dimension of the tumour (r = 0.496, P < 0. 01), its volume (r = 0.439, P < 0.05), spenoid sinus invasion (P < 0. 01) and intracavernous carotid artery (encasement (P < 0.01). The other items were not related to serum GH levels. Since we believe surgery is the first choice of treatment and the cavernous sinus is difficult of access with a conventional surgical approach, preoperative assessment of invasion into the cavernous sinus is critical for predicting the surgical outcome. Low GH levels (5-50 ng/ml) were found with tumours medial to the intercarotid line and high levels (more than 101 ng/ml) with invasive tumours with carotid artery encasement. Variable GH levels were noted with tumours extending beyond the intercarotid line. Because functioning adenomas invading the cavernous sinus tend to have markedly high hormone levels, and only patients with carotid artery encasement showed markedly elevated GH levels, we believe carotid artery encasement a reliable MRI indicator of cavernous sinus invasion.

Acromegaly↗

PubMed2005

Early onset neonatal sepsis.

OBJECTIVE: To study the maternal risk factors and clinico-bacteriological profile of early onset sepsis (EOS), in a tertiary care neonatal unit. METHODS: Relevant data of neonates born during the study period were obtained from their case records. A diagnosis of early onset sepsis was made if either clinical sepsis developed within 72 hours of life or if positive blood/CSF cultures were obtained in those with potential maternal risk factors. Statistical analysis was done using Odds Ratio or Chi-square and Fisher's exact t-test as applicable. RESULTS: Among 1743 live births, a total of 69 episodes of sepsis occurred in 65 neonates (43% culture proven) with an incidence of 37.2 per 1000 live births. The incidence of EOS was 20.7 per 1000 live births and it constituted 55.4% of overall sepsis. Among the perinatal risk factors assessed, a significant association of EOS with prolonged rupture of membranes, foul smelling liquor, dai (midwife) handling and maternal urinary tract infection was observed (p < 0.05). Among infants at risk of EOS, 20.6% developed sepsis compared to only 0.5% of those without these risk factors (p 0.001). Even among those at high risk such as low birth weight, preterm, and asphyxiated neonates, incidence of EOS was negligible in the absence of a maternal risk factor. Pneumonia (66.7%), shock (27.7%), metabolic acidosis (19.4%) and meningitis (8.3%) were the comorbidities seen among the cases. Culture proven EOS occurred in 41.6%, Pseudomonas being the commonest (60%) isolate. The case fatality rate was 19.4%. CONCLUSION: Screening for sepsis in an asymptomatic neonate is warranted only in the presence of a maternal risk factor even if the neonate is at high risk of developing sepsis due to associated problems of prematurity, low birth weight or asphyxia. Knowledge of likely causative organisms of EOS can aid in instituting prompt and appropriate therapy, in order to minimise morbidity and mortality.

Female↗

PubMed1990

Analysis of neurologic symptoms in deep diving: implications for selection of divers.

Eighteen professional divers (age range 24-33 yr, mean 28.3) participated in one simulated dive to 360 meters of seawater (msw) in a helium-oxygen (heliox) atmosphere with equal compression and decompression profiles. All divers were given an extensive neurologic examination before diving. Clinical neurologic symptoms observed during the dives were equilibrium disorder, sleep disturbances, fatigue, nausea, loose stools, stomach pain, tremor, mental disturbances, reduced appetite, and headache. Symptoms were scored individually by each diver. The symptoms were analyzed statistically by factor analysis, which grouped them into four factors. These symptoms are presumably related to functional disturbances in the brain stem and the cerebellum. Factor 3 symptoms (tremor, mental disturbances, reduced appetite) correlated significantly to a history of predive decompression sickness (P = 0.006) and to cerebral concussion (P = 0.023). Three divers were periodically unable to work at bottom due to equilibrium disorder, diarrhea, or nausea. One diver with mild polyneuropathy and slight cerebral atrophy as seen by computerized tomography and another diver with abnormal electroencephalography were periodically unable to work due to equilibrium disorder and nausea, respectively. We advocate that divers with signs of central or peripheral nervous system dysfunction should not be selected for deep diving.

Adult↗

PubMed2001

[Study of quantitative calibration model suitability in near-infrared spectroscopy analysis].

Near-infrared spectroscopy is a fast, high efficiency and low cost analytical technique, that depended on analytical models which are built through near-infrared spectra, the primary method results of calibration set and chemometrics methods. The reliability of analytical results mostly depends on the suitability of analytical model to unknown samples. To judge the suitability of analytical model, a new method is presented that combine principle factor analysis (PCA) and Mahalanobis distance. It is different with traditional method, that the Mahalanobis distance is calculated through PCA factor scores. It can avoid the wavelengths selection problem in traditional method of spectral Mahalanobis distance. Through the determination of cetane number of diesel fuel, some factors that affect model suitability judgement are discussed.

Calibration↗

PubMed1994

Determining the complexity of patient satisfaction with foodservices.

OBJECTIVES: (a) To identify the psychological dimensions representing how patients perceive the quality of foodservice; (b) to identify which dimensions best explain variation in the satisfaction ratings of patients; and (c) to identify subgroups based on individual characteristics of patients and contextual factors. DESIGN: Survey questionnaire. SETTING: Patients of a specialized acute-care urban hospital in Canada. SUBJECTS: One hundred thirty-two hospitalized patients (minimum stay of 5 days) who had not received nutrition counseling. Subjects excluded from the study were patients with notable physical, cognitive, or emotional limitations; patients receiving enteral or parenteral nutrition; and patients from long-term-care units. MAIN OUTCOME MEASURE: Overall satisfaction with meals and with foodservices, and satisfaction with 26 specific foodservice attributes. STATISTICAL ANALYSIS: Factor analysis followed by orthogonal rotation (varimax), stepwise multiple regression analysis, and one-way analysis of variance. RESULTS: Seven dimensions represented patients' perceptions of foodservice: food quality, service timeliness, service reliability, food temperature, attitude of the staff who deliver menus, attitude of the staff who serve meals, and customization. Food quality was the best predictor of patient satisfaction with meals and foodservice, followed by customization and attitude of the staff who deliver menus. Individual characteristics (gender, age, education, perception of degree of control over health, and belief that food influences one's health status) and contextual factors (normal or therapeutic diet, time spent at rest, and appetite) influenced patient satisfaction. IMPLICATIONS: The results emphasize the need for a comprehensive and differentiated approach in measuring and monitoring patient satisfaction with foodservices.

Adolescent↗

PubMed2005

An illustration of multilevel factor analysis.

The factor analysis of repeated measures psychiatric data presents interesting challenges for researchers in terms of identifying the latent structure of an assessment instrument. Specifically, repeated measures contain both within and between individual sources of variance. Although a number of techniques exist for separating out these 2 sources of variance, all are problematic. Recently, researchers have proposed that exploratory multilevel factor analysis (MFA) be used to appropriately analyze the latent structure of repeated measures data. The chief objective of this report is to provide a didactic step-by-step guide on how MFA may be applied to psychiatric data. In the discussion, we describe difficulties associated with MFA and consider challenges in factor analyzing life event appraisals in psychiatric samples.

Adolescent↗

PubMed2003

The impact of endothelial nitric oxide synthase polymorphisms on long-term renal allograft outcome.

A major manifestation of chronic allograft failure (CAF) is the accelerated onset of atherosclerotic lesions within the graft. Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene have been implicated in the pathogenesis of native atherosclerosis. This study tested the hypothesis that polymorphisms in eNOS are associated with susceptibility to CAF after cadaveric renal transplantation. The patient cohort comprised 140 renal transplant recipients who had received their transplants between 1985 and 1997 at the Oxford Transplant Centre and included 61 patients with biopsy-proven CAF and 79 with stable graft function for at least 10 years (long-term survivors, LTS). Genotyping for one polymorphism in the promoter region and two polymorphisms in the coding regions of the eNOS gene was performed by polymerase chain reaction with sequence-specific primers (PCR-SSP). No association was found between any genetic variant and the development of CAF, even after stratification for other known risk factors. Statistical analysis revealed that all three polymorphisms were closely linked. We conclude that recipient eNOS gene polymorphisms do not alter the risk of CAF after renal transplantation.

Cadaver↗

PubMed2005

Evaluation of outcome after immediate breast reconstruction: prospective comparison of four methods.

BACKGROUND: Little is known about the association among different methods to assess outcome following breast reconstruction. The aim of this study was to comprehensively compare four distinct methods of outcome evaluation following immediate breast reconstruction. METHODS: There were 102 women who were prospectively evaluated: 46 patients had submuscular implants, and 56 patients had implant-assisted latissimus dorsi breast reconstruction. The mean patient age at the time of operation was 46 years (range, 22 to 72 years), with a mean follow-up of 18 months (range, 12 to 24 months). All patients were evaluated using geometric measurements, photographs, linear analogue scores, and a quality-of-life questionnaire. The Wilcoxon signed rank test, Spearman's correlation, and factor analysis statistics were used. RESULTS: Transverse breast width, vertical breast height, sternal notch-nipple, midclavicular line-nipple, nipple-inframammary crease, midline-nipple, internipple, and intermammary measurements were reproducible and reliable. Median differences of absolute vertical and horizontal differences were less than 1 cm and were associated with high levels of patient satisfaction. Assessors asked to score photographs without being specifically requested to consider shape, cleavage, or symmetry would focus mainly on vertical and horizontal differences. There was a high correlation between surgeon and patient linear analogue scores. Quality-of-life questionnaires provide valuable information on body image, physical effects, and continued cancer worry. Factor analyses failed to identify components to compress data fields to obtain equivalent information from fewer questions. CONCLUSIONS: Evaluation of immediate breast reconstruction is complex. Cumbersome data collection has to be balanced against practical variables that individual units can collect to evaluate outcome for audit and research.

Adult↗

PubMed1995

Use of the multitrait multimethod (MTMM) to analyze family relational data.

In this article, the authors propose the logic of the multitrait multimethod (MTMM) approach for analysis of data as an alternative solution for examining family relational data. Application of the MTMM logic permits the assessment of common perspectives shared by all family members and of the unique perspectives of individuals. The advantages of using this approach in family research include the ability to (a) maintain consistency between systems theory views of family-as-a-unit, and (b) delineate patterns of agreement, disagreement, or both among family members.

Adult↗

PubMed2003

Computing measures of simplicity of fit for loadings in factor-analytically derived scales.

A very simple structure is sought when factor analysis is used to develop measurement scales. The SIMLOAD program computes measures of factorial simplicity for rows and columns of loading matrices (usually the factor pattern) as well as some overall measures. These include Kaiser's (1974) index of factorial simplicity for variables (rows), the author's scale fit index for factors (columns), Bentler's (1977) scale-free matrix measure, and hyperplane counts. Routine use of these measures is recommended for multifactor scale development. The measures may also be useful in more general factor applications and in confirmatory as well as exploratory analyses. SIMLOAD also computes factor scale intercorrelations, scale alpha coefficients (including alpha when an item is removed), and sorted loadings for ease of interpretation.

Data Interpretation, Statistical↗

PubMed2001

Structure of lifestyle disruptions in chronic disease: a confirmatory factor analysis of the Illness Intrusiveness Ratings Scale.

BACKGROUND: The Illness Intrusiveness Ratings Scale (IIRS) measures the extent to which disease or its treatment or both interfere with activities in important life domains. Before comparing IIRS scores within or across groups it is crucial to determine whether a common underlying factor structure exists across patient populations. OBJECTIVE: To investigate the factor structure underlying the IIRS and evaluate its stability across diagnoses. METHODS: IIRS responses from 5,671 respondents were pooled from 15 separate studies concerning quality of life in eight patient groups: rheumatoid arthritis; osteoarthritis; systemic lupus erythematosus; multiple sclerosis; end-stage renal disease (maintenance dialysis); renal transplantation; heart, liver, and lung transplantation; and insomnia. Data were gathered by different methods (eg, interview, self-administered, mail survey) and in diverse contexts (eg, individual vs. group). RESULTS: Exploratory maximum-likelihood factor analysis identified three underlying factors in a randomly selected subset of respondents (n = 400), corresponding to "Relationships and Personal Development," "Intimacy," and "Instrumental" life domains. Confirmatory factor analysis corroborated the stability of this structure in an independent subsample (n = 2100). Complementary goodness-of-fit indices confirmed the consistency of the three-factor solution, corroborating that IIRS scores are uniquely defined across patient populations. Coefficient alpha was high for total and subscale scores. CONCLUSIONS: IIRS scores can be compared meaningfully within and across patient groups. Both total and subscale scores can be used depending on research objectives.

Adult↗

PubMed1991

The construction of a scored neonatal neurological examination for assessment of neurological integrity in full-term neonates.

We describe the construction of a scored form for the neurological examination of the full-term neonate. Extensive data analyses were obtained from a large sample of neonatal neurological examinations performed by one examiner (MSP). Examinations were used from neonates with ages less than or equal to 48 hours (n = 727) and 72 hours to 1 week (n = 510) with gestational ages greater than or equal to 37 weeks. Forty-four items from several neonatal assessments were used in these neurological examinations. Further subdivision yielded a total of 65 items. Correlations were obtained for the 65 items. We factored the matrix of these correlations, using several solutions of factor analysis. Thirty-two items were thus grouped and pruned into seven dimensions (factors) to provide a scorable neonatal neurological examination (Neoneuro) with an internal consistency or reliability of 0.80. From the total scores, cut points are recommended for categories of normality/abnormality: normal, mildly abnormal, moderately abnormal, and severely abnormal. This scoring system is well-based both theoretically and psychometrically. The quantified computer-compatible scoring system permits evaluation of individual neonates, as well as comparison of samples of neonates on item scores, subscores (factor scores), and total scores. Such quantification will permit documentation of the natural history of specific abnormalities and the evaluation of various therapies.

Brain Damage, Chronic↗

PubMed2004

Increasing the reliability of ipsative interpretations in neuropsychology: a comparison of reliable components analysis and other factor analytic methods.

Ipsative approaches to neuropsychological assessment typically involve interpreting difference scores between individual test scores. The utility of these methods is limited by the reliability of neuropsychological difference scores and the number of comparisons between scores. The present study evaluated the utility of difference scores using factor analytic methods, including reliable components analysis (RCA), equally weighted composites and individual neuropsychological measures. Data from 1,364 individuals referred for neuropsychological assessment were factor analyzed and the resulting solutions were used to compute composite scores. Reliabilities and confidence intervals were derived for each method. Results indicated that RCA outperformed other factor analytic methods, but produced a slightly different factor structure. Difference scores derived using orthogonal solutions were slightly more reliable than oblique methods, and both were more reliable than those from equally weighted composites and individual measures. Confidence intervals for difference scores were considerably smaller for factor methods relative to those for individual test comparisons, due to the greater reliability of factor based difference scores and the smaller number of comparisons required. These findings suggest that difference scores derived from orthogonal factor solutions, particularly RCA solutions, may improve reliability for clinical assessment purposes.

Adolescent↗

PubMed2006

Gender-related differences in dyspepsia: a qualitative systematic review.

BACKGROUND: Relative to men, women are diagnosed more frequently with functional gastrointestinal (GI) disorders. With increased awareness of basic gender differences in perception and treatment of visceral pain, there has been new interest in research on gender disparity in the care of people with functional GI disorders. Past attention has focused on irritable bowel syndrome, whereas gender differences in other disorders are less well described. OBJECTIVE: Our aim was to systematically review studies that have examined gender-related differences among patients with dyspepsia. METHODS: MEDLINE, HealthSTAR, and PsycINFO databases were searched for English-language articles on dyspepsia published between 1966 and August 2001. Epidemiologic studies, clinical trials, review articles, and conceptual articles from peer-reviewed journals were included for review. Findings were summarized and discussed within a framework of biological and psychosocial factors. Statistical analysis of combined data was inappropriate because of the inconsistent definition of dyspepsia among different studies and wide variation in the types of articles reviewed. RESULTS: Studies that examine gender-related differences in patients with dyspepsia have focused their investigations on the clinical epidemiology and pathophysiology of dyspepsia. In most epidemiologic studies, no gender analysis was performed beyond a description of sample demographics, and when statistical significance was tested, few consistent gender differences were found. Overall, it appears that men and women with dyspepsia possibly differ with respect to pattern of symptoms, pain perception or modulation, and antinociceptive mechanisms, but these observations have not been confirmed. No study evaluated the clinical implications of these possible differences. CONCLUSIONS: Future efforts should be directed to not only examine gender-related differences in the clinical epidemiology of dyspepsia, but also understand their clinical significance. Therefore, well-designed population-based studies using a consistent definition of dyspepsia are needed to investigate the prevalence of dyspepsia symptoms and patterns of dyspepsia management among men and women.

Domestic Violence↗