PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “predictive modelling”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources
PubMed1997

Prognostic factors in meningococcal disease. Development of a bedside predictive model and scoring system. Barcelona Meningococcal Disease Surveillance Group.

CONTEXT: Meningococcal disease is associated with significant morbidity and mortality. Development of a prognostic model based on clinical findings may be useful for identification and management of patients with meningococcal infection. OBJECTIVES: To construct and validate a bedside model and scoring system for prognosis in meningococcal disease. DESIGN: Prospective, population-based study. SETTING: Twenty-four hospitals in the metropolitan area of Barcelona, Spain. PATIENTS: A total of 907 patients with microbiologically proven meningococcal disease. Patients diagnosed with meningococcal disease from 1987 through 1990 were used to develop the prognostic model, and those diagnosed in 1991 and 1992 were used to validate it. OUTCOME MEASURES: Clinical independent prognostic factors for mortality in meningococcal disease. The association between outcome and independent prognostic factors was determined by logistic regression analysis. A scoring system was constructed and tested using receiver operating characteristic curves. RESULTS: Among 624 patients in the derivation set, 287 (46%) were male, the mean age was 12.4 years, and 34 patients (5.4%) died. Among 283 patients in the validation set, 124 (43.8%) were male, the mean age was 12.7 years, and 17 patients (6.0%) died. In multivariate analysis, independent predictors of death were hemorrhagic diathesis (odds ratio [OR], 101; 95% confidence interval [CI], 30-333), focal neurologic signs (OR, 25; 95% CI, 7-83), and age 60 years or older (OR, 10; 95% CI, 3-34), whereas receipt of adequate antibiotic therapy prior to admission was associated with reduced likelihood of death (OR, 0.09; 95% CI, 0.02-0.4). Hemorrhagic diathesis was scored with 2 points, presence of focal neurologic signs with 1 point, age of 60 years or older with 1 point, and preadmission antibiotic therapy was scored as -1. The clinical scores of -1, 0, 1, 2, and 3 or more points were associated with a probability of death of 0%, 2.3%, 27.3%, 73.3%, and 100%, respectively. CONCLUSIONS: Hemorrhagic diathesis, focal neurologic signs, and age of 60 years or older were independent predictors of death in meningococcal disease, whereas receipt of adequate antibiotic therapy was associated with a more favorable prognosis. The scoring system presented is simple, is based on findings readily available at the bedside, and may be useful to help guide aggressive therapy.

Adolescent↗
PubMed1989

Choice (CRT) and simple reaction times (SRT) compared in laboratory technicians: factors influencing reaction times and a predictive model.

Choice reaction time (CRT) and simple reaction time (SRT) tests were administered to 151 female histology laboratory technicians to determine if occupational exposure to organic solvents and formaldehyde delayed either or both. The relationships between CRT and SRT latencies were evaluated using different testers, sequences of administration, and microcomputers. Formaldehyde exposure, cigarette smoking history, ethnicity, and alveolar CO levels did not significantly influence CRT and SRT. However, slightly different protocols did significantly affect SRT. A linear model demonstrated that logSRT (LSRT) and LogCRT (LCRT) were longer with increasing age, promising further clinical applications. It is concluded that both CRT and SRT measure some overlapping and some different neurologic pathways. Reaction times in large "normal" populations are needed to compare with groups exposed to potential neurotoxins.

Adult↗
PubMed2004

A breast cancer prediction model incorporating familial and personal risk factors.

Many factors determine a woman's risk of breast cancer. Some of them are genetic and relate to family history, others are based on personal factors such as reproductive history and medical history. While many papers have concentrated on subsets of these risk factors, no papers have incorporated personal risk factors with a detailed genetic analysis. There is a need to combine these factors to provide a better overall determinant of risk. The discovery of the BRCA1 and BRCA2 genes has explained some of the genetic determinants of breast cancer risk, but these genes alone do not explain all of the familial aggregation of breast cancer. We have developed a model incorporating the BRCA genes, a low penetrance gene and personal risk factors. For an individual woman her family history is used in conjuction with Bayes theorem to iteratively produce the likelihood of her carrying any genes predisposing to breast cancer, which in turn affects her likelihood of developing breast cancer. This risk was further refined based on the woman's personal history. The model has been incorporated into a computer program that gives a personalised risk estimate.

Adult↗
PubMed2005

Ultrasound diagnosis of fetal macrosomia: a comparison of weight prediction models using computer simulation.

OBJECTIVE: To assess the frequency of the diagnosis of macrosomia in relation to differing weight estimation formulae in unselected pregnancies. METHODS: Computer modeling techniques were employed. Computer modeling software generated correlated fetal biometry measurements according to published British standards, from 37 to 41 weeks' gestation. For each set of measurements, estimated fetal weights were obtained by a panel of 18 ultrasound weight formulae. The diagnosis of macrosomia was made if the fetal weight estimate was greater than 4500 g. Cohorts of 5000 pregnancies for each week of gestation were studied. RESULTS: The frequency of diagnosis of macrosomia increased progressively with advancing gestational age, with large increases between 40 and 41 weeks. The type of weight estimation formula had a profound influence on the frequency of diagnosis of macrosomia. Five of the formulae tested almost never returned a weight estimate greater than 4500 g. Three formulae yielded false positive rates in excess of 15%. The Hadlock group of formulae yielded frequencies of 0.3% to 14.6%. CONCLUSIONS: Most formulae tend to over-diagnose macrosomia at term. Intervention rates for suspected fetal macrosomia may be influenced by gestational age at the time of scan and the type of fetal weight estimation formula in use.

Birth Weight↗
PubMed1997

Predictive Model for the Calculation of Interfacial Tension in Nonideal Electrolytic Systems

A new model is proposed for the calculation of the interfacial tension between an organic solvent and concentrated aqueous solutions of electrolytes. The interfacial tension is derived from the isothermal Gibbs equation. The increase or decrease of interfacial tension with concentrations are modeled using a Langmuir-type adsorption equation and the strong non-ideality of the mixtures is taken into account through the Mikulin equation. The model parameters are first determined with binary water-electrolyte solutions and are kept constant in the case of mixtures. The model has been applied to chloride solutions-chloride salts of various metals and hydrochloric acid-and compared with experimental data obtained by using the pendant drop technique and a Wilhelmy tensiometer. In all cases investigated, good agreement is observed, even in the case of stiff variations of interfacial tension with the electrolyte concentration and also at high concentrations of electrolytes.

Journal Article↗
PubMed1986

Effects of forskolin and cyclic nucleotides in animal models predictive of antidepressant activity: interactions with rolipram.

Forskolin, a direct activator of the catalytic subunit of adenylate cyclase (AC), and the cyclic nucleotide analogs dibutyryl cAMP (dBcAMP), 8-bromo cAMP (8-BrcAMP) and dibutyryl cGMP (dBcGMP) were tested for their ability to reverse the hypothermia or hypokinesia of mice depleted of presynaptic endogenous monoamines by pretreatment with reserpine, alpha-methyl-p-tyrosine and p-chlorophenylalanine. Forskolin and the cAMP analogs decreased the rectal temperature and inhibited locomotor activity in normal mice. In mice depleted of brain monoamines forskolin reversed the hypothermia and hypokinesia; dBcAMP and 8-BrcAMP antagonized the hypothermia but were only marginally effective in reversing the hypokinesia. DBcGMP was inactive. The antihypothermic action of forskolin or salbutamol was enhanced by the novel antidepressant and cAMP selective phosphodiesterase inhibitor rolipram (4RS-[3-cyclopentyloxy-4-methoxy-phenyl]-2-pyrrolidone). As an indirect effect via release of endogenous monoamines stimulating postsynaptic receptors was precluded by the monoamine-depleting pretreatment, forskolin and the cAMP analogs are thought to exert their antidepressant action by directly increasing brain cAMP availability. This is achieved by forskolin via activation of the catalytic subunit of AC and by the cAMP analogs via substitution for cAMP. These findings suggest that antidepressant activity is crucially linked to enhanced cAMP availability within brain effector cells. The successful treatment of endogenously depressed patients with rolipram supports this assumption.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1992

Genomic mapping by single copy landmark detection: a predictive model with a discrete mathematical approach.

One of the goals of the Human Genome Project is to produce libraries of largely contiguous, ordered sets of molecular clones for use in sequencing and gene mapping projects. This is planned to be done for human and many model organisms. Theory and practice have shown that long-range contiguity and the degree to which the entire genome is covered by ordered clones can be affected by many biological variables. Many laboratories are currently experimenting with different experimental strategies and theoretical models to help plan strategies for accomplishing long-range molecular mapping of genomes. Here we describe a new mathematical model and formulas for helping to plan genome mapping projects, using various single-copy landmark (SCL) detection, or "anchoring", strategies. We derive formulas that allow us to examine the effects of interactions among the following variables: average insert size of the cloning vector, average size of SCL, the number of SCL, and the redundancy in coverage of the clone library. We also examine and compare three different ways in which anchoring can be implemented: (1) anchors are selected independently of the library to be ordered (random anchoring); (2) anchors are made from end probes from both ends of clones in the library to be ordered (nonrandom anchoring); and (3) anchors are made from one end or the other, randomly, from clones in the library to be ordered (nonrandom anchoring). Our results show that, for biologically realistic conditions, nonrandom anchoring is always more effective than random anchoring for contig building, and there is little to be gained from making SCL from both ends of clones vs. only one end of clones.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Mapping↗