PubMed Health⌕ Search

Biomedical subjects

S Ogston

Publications and source records attributed to S Ogston.

32 records · Page 2Linked to original sources
PubMed1997

The diagnostic accuracy of cervico-vaginal fetal fibronectin in predicting preterm delivery: an overview.

OBJECTIVE: To determine the accuracy with which cervico-vaginal fetal fibronectin predicts preterm delivery using systematic quantitative overview of the available literature. DESIGN: Online searching of MEDLINE database (1966 to April 1996), scanning of bibliography of known primary and review articles and review of recent journal issues. Study selection, assessment of study quality and data extraction were performed in duplicate under masked conditions. Likelihood ratios were generated in subgroups of symptomatic and asymptomatic pregnant women by pooling data from different studies. An LR of > 10 or < 0.1 indicated conclusive changes in the pretest probability of preterm delivery while an LR of 5-10 or 0.2-0.1 indicated only moderate changes. PARTICIPANTS: Seven hundred and twenty-three symptomatic women with threatened preterm labour included in nine studies and 847 asymptomatic women (635 low risk and 212 high risk) included in six studies selected for meta-analyses. MAIN OUTCOME MEASURES: Likelihood ratios for positive and negative test results using delivery at < 37 and < 34 weeks of gestation, and within one week of testing as outcome measures. RESULTS: In symptomatic women a positive test predicted delivery < 37 weeks of gestation with a pooled likelihood ratio (LR) of 4.6 (95% CI 3.5-6.1) while a negative test had a pooled LR of 0.5 (95% CI 0.4-0.6). For delivery < 34 weeks of gestation, the pooled LR was 2.6 (95% CI 1.8-3.7) for a positive test and 0.2 (95% CI 0.1-0.5) for a negative test. For delivery within one week of testing, the pooled LR was 5.0 (95% CI 3.8-6.4) for a positive test and 0.2 (95% CI 0.1-0.4) for a negative test. In asymptomatic women at low risk of delivery < 37 weeks of gestation the pooled LR was 3.2 (95% CI 2.2-4.8) for a positive test and 0.8 (95% CI 0.7-0.9) for a negative test. In high risk asymptomatic women using delivery < 37 weeks of gestation as an outcome measure the pooled LR was 2.0 (95% CI 1.5-2.6) for a positive test and 0.4 (95% CI 0.2-0.8) for a negative test. For delivery < 34 weeks of gestation in high risk, asymptomatic women the pooled LR was 2.4 (95% CI 1.8-3.2) for a positive test and 0.6 (95% CI 0.4-0.9) for a negative test. CONCLUSION: The presence of fetal fibronectin in cervico-vaginal mucus has limited accuracy in predicting preterm delivery as the likelihood ratios for positive and negative test results generated only minimal to moderate changes in the pretest probability of preterm birth.

Cervix Uteri↗
PubMed1996

Standards for the quantification of serial changes in the amniotic fluid index.

A total of 274 low-risk pregnancies underwent predetermined scheduled serial ultrasound examinations and measurements of the amniotic fluid index (AFI). As expected from previous cross-sectional studies, there is a gradual decline in the AFI from mid-trimester until term. The longitudinal nature of this data set permits the construction of conditional centiles for AFI whereby the AFI of an individual fetus at a given gestational age can be extrapolated to give a range of expected values for AFI (expressed as centiles) at a later gestational age. Examples of conditional centiles based upon 4-week measurement separations are presented. These conditional centiles permit the appropriate evaluation and quantification of time-dependent changes in AFI to be made.

Amniotic Fluid↗
PubMed1996

Observer variability in histopathological reporting of non-small cell lung carcinoma on bronchial biopsy specimens.

AIMS: To evaluate the ability of histopathologists to sub-classify non-small cell lung carcinomas on bronchial biopsy material using the current World Health Organisation (WHO) classification. METHODS: Twelve histopathologists each reviewed 100 randomly selected bronchial biopsy specimens which had originally been reported as showing non-small cell lung carcinoma. For each case, two sections were circulated, one stained by haematoxylin and eosin and the other by a standard method for mucin (alcian blue/periodic acid Schiff). The participants were allowed to indicate their degree of confidence in their classification of each case. A standard proforma was completed and the results were analysed using kappa statistics. RESULTS: Where the participants were confident in their classification, they were actually quite good at sub-classifying the non-small cell carcinoma sections (kappa = 0.71, standard error = 0.058). Overall, however, the results were only fair (kappa = 0.39, standard error = 0.034). CONCLUSIONS: The majority of non-small cell lung carcinomas can be correctly categorised on adequate bronchial biopsy material. Where a confident diagnosis was made, both squamous carcinoma (kappa = 0.73) and adenocarcinoma (kappa = 0.83) were well recognised.

Adenocarcinoma↗
PubMed1996

Nebulised antipseudomonal antibiotic therapy in cystic fibrosis: a meta-analysis of benefits and risks.

BACKGROUND: To establish the benefits and risks of nebulised antipseudomonal therapy in cystic fibrosis the results of relevant randomised controlled trials were combined. METHODS: The therapeutic end points compared were (a) number of pulmonary exacerbations requiring treatment with systemic antibiotics, (b) measurable alteration in respiratory tract pseudomonal load, (c) alteration in lung function on spirometric assessment, (d) development of resistance in respiratory tract Pseudomonas strains to the nebulised antipseudomonal used in each randomised controlled trial, and (e) renal and auditory impairment. RESULTS: Five studies were suitable for meta-analysis, eight others could not be included because of inadequate outcome description or the lack of appropriate randomisation. Meta-analysis shows benefit for nebulised antipseudomonal antibiotic therapy with no demonstrable adverse effect other than a possible increase in in vitro antibiotic resistance of Pseudomonas aeruginosa of the respiratory tract. CONCLUSIONS: Although inferences drawn from individual randomised controlled trials concerning the benefits and risks of this form of therapy are conflicting, pooled effect size establishes benefit with nebulised antipseudomonal antibiotic therapy and emphasises its relevance to the integration of information in other areas of controversy relating to the treatment of this disease.

Administration, Inhalation↗
PubMed1994

Observer variability in histopathological reporting of malignant bronchial biopsy specimens.

AIMS: To evaluate the ability of histopathologists to classify lung carcinomas on bronchial biopsy material using the current World Health Organisation (WHO) classification. METHODS: Eleven histopathologists each reviewed 100 randomly selected bronchial biopsy specimens which had originally been reported as showing lung carcinoma. A single haematoxylin and eosin stained section from each case was circulated and a standard proforma completed. These were analysed using kappa statistics. RESULTS: The histopathologists were excellent at distinguishing between small cell and non-small-cell carcinoma kappa = 0.86), but not so good at subclassifying the non-small cell carcinoma group kappa = 0.25). CONCLUSIONS: The clinically important distinction between small cell and non-small cell carcinoma of the lung is reliably made by competent histopathologists even on limited material.

Biopsy↗
PubMed1994

Early detection of metabolic abnormalities in preterm infants impaired by disorders of blood glucose concentrations.

We recently reported (Acta Paediatr Scand 1992;8: 580-4) three preterm infants with severe respiratory distress syndrome and abnormal glucose profiles for the first 5 days of life who subsequently died in infancy; only at autopsy were they shown to have abnormal glucose-6-phosphatase activity. We have therefore studied retrospectively in a matched cohort of 109 infants the blood glucose profiles correlated with the severity of respiratory distress syndrome (expressed as the fraction of inspired oxygen, FiO2): group A, mild, FiO2 < 0.25; group B, moderate, FiO2 0.26-0.50; group C, severe, FiO2 > 0.51. All groups had a similar frequency of low blood glucose values (15% < or = 2.2 mmol/L; 29% < or = 2.6 mmol/L), but high blood glucose values and greater variability in glucose values were more common in groups B and C despite lower caloric intakes (A, 4.3%; B, 9.3%; C, 9.6% > or = 7 mmol/L). We conclude that the early blood glucose patterns in those three previously described preterm infants with abnormal hepatic glucose-6-phosphatase activity at autopsy cannot be viewed as abnormal when considered against a matched cohort of infants. Preterm infants at risk of genetic or developmental delays in blood glucose homeostasis should be reassessed after recovery from their acute illnesses.

Blood Glucose↗
PubMed1993

Variability of self reported measures of alcohol consumption: implications for the association between drinking in pregnancy and birth weight.

STUDY OBJECTIVE: To describe the intra-subject variability of self reported maternal alcohol consumption using different ways of collecting information and to analyse the implications of this variability for research into the effect of low to moderate maternal alcohol consumption on birth weight. DESIGN: This was a longitudinal study. Self reported maternal alcohol consumption before, during, and after pregnancy was assessed on four occasions over two years. The data were collected by two self administered questionnaires and during two personal interviews (one by phone and another face to face). SETTINGS: The Obstetrics Department, Odense University Hospital, Odense, Fünen, Denmark. PARTICIPANTS: A total of 2880 pregnant women were recruited consecutively from the hospital catchment area. Altogether 328 pregnant women and their babies were selected. All women who reported an average alcohol consumption of five drinks or more per week were recruited to the study (164 women) and a 1:1 control group was selected from the remaining women based upon two matching criteria: expected date of delivery and the women's year of birth. Some 279 women (85%) completed the study. MEASUREMENTS AND MAIN RESULTS: Self reported alcohol consumption (number of drinks per week) and birth weight (g) were the main outcomes. Women's self reported alcohol consumption varied over time and according to the data collection method. When different methods of data collection were used to assess alcohol intake in similar periods of time, significant differences in reporting were found despite the relatively high correlations between the measurements. Although a consistent reduction in birth weight with increasing consumption of alcohol was found, there were differences in the shape and strength of this association when comparing the six available alcohol measurements. CONCLUSIONS: The type of questions used, the way the data were collected, the period of time referred to, and the time the questions were asked, should be taken into consideration when describing the drinking pattern of pregnant women. Furthermore, birth weight results from studies that have used different alcohol measures should be interpreted or compared with caution because of possible large differences resulting from the differing methods of assessing fetal exposure to alcohol.

Alcohol Drinking↗
PubMed1990

Predicting death from initial disease severity in very low birthweight infants: a method for comparing the performance of neonatal units.

OBJECTIVES: To investigate (a) which clinical variables and physiological measures of disease severity best predict death in very low birthweight infants and (b) their use in comparing mortality between two neonatal units. DESIGN: Retrospective study of two cohorts of very low birthweight infants from overlapping time periods who received mechanical ventilation. SETTING: Two neonatal intensive care units (hospitals A and B). SUBJECTS: 262 Very low birthweight infants, 130 in hospital A, 132 in hospital B. MAIN OUTCOME MEASURE: Death in hospital. RESULTS: In hospital A the mean level of oxygenation in the first 12 hours of life, whether measured as inspired oxygen requirement (FIO2), arterial/alveolar oxygen (a/AO2) ratio, or alveolar-arterial oxygen difference (A-aDO2), was more closely associated with death than any of four "traditional" risk factors: low birth weight, short gestation, the diagnosis of respiratory distress syndrome, and male sex. Mean pH in the first 12 hours was as strongly associated with death as birth weight. Multiple logistic regression models were derived in infants from hospital A using the four traditional risk factors with measures of oxygenation and pH. The validity of each model was then tested in infants from hospital B. The model based on the four traditional risk factors alone predicted death in hospital B with only 31% sensitivity. Adding mean a/AO2 ratio and mean pH increased its sensitivity to 75%, and when mean a/AO2 ratio was replaced by mean FIO2 its sensitivity increased further to 81%. Based on crude mortality rates alone, the odds of death in hospital A versus hospital B were 0.67 (95% confidence interval 0.37 to 1.23). After correcting for traditional risk factors and mean FIO2 and mean pH, however, the odds of death in hospital A increased to 3.27 (1.35 to 7.92; p less than 0.01). This increased risk persisted after adjusting for the time difference between each cohort. CONCLUSIONS: Crude comparisons of hospital mortality can be highly misleading. Reliable assessment of neonatal outcome is impossible without correcting for major risk factors, particularly initial disease severity. International agreement on a minimum core dataset of clinical and physiological information could improve neonatal audit and help to identify effective treatments and policies.

Gestational Age↗
PubMed1989

A controlled study of the ocular effects of tamoxifen in conventional dosage in the treatment of breast carcinoma.

The use of tamoxifen is expanding in its application in the treatment of breast carcinoma, and proposed prophylactic use. Tamoxifen in high dosage and in some reports at conventional dosage is associated with ocular toxicity. This study in a single blind fashion examined 79 patients receiving tamoxifen for varying treatment durations at conventional dosage and 115 patients not receiving tamoxifen. No ocular toxicity was found. Further follow up studies are required to ensure no toxicity develops in patients receiving high cumulative dosage on conventional therapy.

Aged↗
PubMed1985

A study of white finger in the gas industry.

Men engaged in breaking or reinstating road surfaces are exposed to vibration from mechanical tools. In view of the lack of epidemiological information on vibration white finger in such a population, a survey was carried out to identify the prevalence of symptoms of white finger in a sample of men using these tools in the gas industry and to compare the prevalence with that found in a control group not occupationally exposed to vibration. Altogether 905 men (97%) in the gas industry and 552 men (92%) in the control group were interviewed, using a questionnaire from which the presence or absence of white finger symptoms from all causes was noted. The prevalence of white finger was 9.6% in the group exposed to vibration at work compared with 9.5% in the control group. The prevalence in the former group when adjusted for age differences between the survey and control populations was 12.2%, but this difference did not reach statistical significance. In case the approach of comparing prevalences of white finger from all causes might have obscured any contributory effect of vibration, the prevalence of white finger was examined in relation to the number of years vibrating tools had been used, this being the only measure of exposure to vibration available. No direct association was found between the prevalence of symptoms and number of years vibrating tools had been used. In view of this and the absence of a significant excess of white finger symptoms in the group using vibratory tools, the authors conclude that vibration white finger is not a special problem in the gas industry. Nevertheless, experimental tests carried out on the different types of roadbreakers used in the industry and on different road surfaces indicate that the vibration levels exceed the standards advocated in the draft international standard DIS 5349 (1979) at the lower end of the frequency spectrum. That no particular problem has been found may be due to the relatively short exposures to vibration experienced by the operators or the fact that they are able to grip the tools lightly, or even, possibly, that the standards suggested in DIS 5349 do not accurately reflect the risk of vibration white finger when they are exceeded at the lower end of the frequency spectrum for vibrating tools such as roadbreakers.

Adult↗
PubMed1984

The relationship between liver function tests and alcohol intake in patients admitted to an alcoholism unit.

Values of various blood plasma tests have been determined in heavy drinkers admitted to an Alcoholism Unit and in a reference group of occasional social drinkers. These tests were total protein, albumin, bilirubin, alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), aspartate amino transferase (AST) and amylase. The aim of this study was to assess the reliability and validity of GGT and AST as indices of alcohol intake in heavy drinkers entering an Alcoholism Unit. The data indicate that in the patients group intra-personal variance and analytical variances are relatively small compared with the between-person variance. The data also indicate, however, that in the patients group GGT and AST are not valid group indices of alcohol intake since the between-person variation is large and the correlation with alcohol intake is weak due to large differences in the dose-response relationship between individuals. AST and GGT are poor indicators of alcohol intake in admissions to an Alcoholism Unit.

Adult↗
PubMed1983

The influence of age on lithium efficacy and side-effects in out-patients.

One hundred and sixty-six unipolar and bipolar out-patients (21-78 years) on long-term lithium treatment were studied on a prospective basis. Although there was a possible tendency for manic attacks to increase in prevalence and severity with age, it was difficult to demonstrate a general age-related decline in lithium efficacy. There was a tendency for the prevalence and severity of fine hand tremor to increase with age. This was not seen with polydipsia/polyuria, the other typical lithium side-effect.

Adult↗