Principal Predictors Research Articles

Predictors of Outcome Following Brief Psychodynamic-Interpersonal Therapy for Deliberate Self-Poisoning

We found that brief psychodynamic-interpersonal therapy was more helpful than usual care in deliberate self-poisoning patients, and resulted in reduced suicidal ideation and repetition of self-harm in the 6 months post-treatment. Here, we explore which baseline factors predicted outcome following treatment. Patients presenting to an emergency department with deliberate self-poisoning were randomly assigned to brief psychodynamic-interpersonal therapy (PIT) or usual care. Severity of suicidal ideation 6 months post-treatment was used as the main outcome measure. Sociodemographic features and baseline psychological measures were used as predictor variables. Univariate and regression analyses were used to identify predictors of outcome for the whole group and for those who received psychotherapy. Principal predictors for the psychotherapy group were baseline severity of depression and a prior history of self-harm. For the group as a whole predictors were severity of suicidal ideation, anxiety and prior history of self-harm. Four session PIT for deliberate self-poisoning is effective in reducing suicidal ideation in patients with less severe depression, no prior history of self-harm, and who have not consumed alcohol with the overdose. Extended therapy may be indicated for those with more severe depression.

Early neutrophil engraftment following autologous BMT provides a functional predictor of long-term hematopoietic reconstitution.

Previous studies have demonstrated that the number of CD34+ progenitor cells in the stem cell graft is highly predictive of the rapidity of short-term hematopoietic engraftment. The aim of this study was to identify factors that predict long-term hematopoietic reconstitution (LHR) following autologous BMT. To identify predictors of LHR, peripheral blood counts and marrow biopsies were evaluated at 1 year after transplant in 81 patients with B-cell non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia who underwent autologous BMT. Results were correlated with CD34+ cell dose, granulocyte-monocyte colony-forming units (CFU-GM) infused, and time to neutrophil engraftment (TNE). Total MNC dose, CD34+ cell dose, and CFU-GM infused were significantly associated with TNE (p = 0.011, p < 0.0001, and p = 0.078, respectively). Patients with chronic lymphocytic leukemia were more likely to have received a low CD34+ cell dose than patients with B-cell non-Hodgkin's lymphoma (p = 0.01). Among the four principal predictors, only TNE showed consistent significant correlation with WBC, absolute neutrophil, and platelet count at 1 year after transplant. Logistic regression model showed that TNE was a more sensitive predictor of LHR than either CD34+ cell dose or CFU-GM infused. TNE is an in vivo functional measure of LHR and is a more sensitive predictor of LHR at 1 year after BMT than either CD34+ cell dose or CFU-GM infused.

Using Neural Nets to Model the Spatial Distribution of Seasonal Homes

Seasonal and second homes are important aspects of recreational tourism. Owning a summer cottage, time-share condominium, hunting cabin, or a part-time residence in a location away from home affects development patterns in significant ways. This paper presents the results of using an artificial neural network and a geographic information systems-based approach to identify and quantify the principal predictors of seasonal home distribution within the Lake States region of Minnesota, Wisconsin, and Michigan. Representative variables, such as proximity and spatial configuration of lakes, proximity to the Great Lakes shore, surrounding forest acreage, and public land access have been quantified using geographic information systems at the minor civil division (MCD) scale for the three states. The GIS data have then been fed into artificial neural networks to enable these pattern recognition tools to identify the principal predictors of seasonal home distribution in the Upper Great Lakes States.

THE PREDICTORS OF CHILDREN'S GEOGRAPHICAL KNOWLEDGE OF OTHER COUNTRIES

This study investigated the predictors of children's geographical knowledge of other countries and, in particular, whether a child's demographic characteristics, travel experience, and affect towards a country predict the child's level of geographical knowledge about that country. 261 English children aged between 6 and 13 years old were interviewed in order to assess their affect for, and knowledge of, five specific countries: France, Germany, Ireland, Italy and Spain. The children's travel experience to these countries was also assessed. The children comprising the sample were differentiated in terms of their age, gender, social class and locality (urban versus rural). It was found that the predictors of the children's geographical knowledge varied across the five target countries. There were demographic differences in children's travel experience, with age and social class being the principal predictors of travel. Travel experience to a particular country did sometimes predict the level of positive affect towards that country, but travel did not usually predict geographical knowledge of that country. Affect towards a country also did not predict geographical knowledge of that country. However, there were demographic differences in knowledge: age was found to be the most important predictor of knowledge, with additional independent contributions also being made by social class and gender in the case of some target countries. It is suggested that previous studies which have concluded that there is either a linear or curvilinear relationship between affect and knowledge in this domain might have ignored the covariance of the predictors of geographical knowledge, and that multivariate statistical procedures are required in order to identify relationships between variables in this domain.

Outcome in consecutive emergency department attenders following a road traffic accident

Little is known about the consequences of road traffic accidents. To determine psychological and social outcome at 3 months and 1 year following a road traffic accident. A cohort study of a 1-year sample of consecutive attenders (n=1148) aged 17-69 years at the accident and emergency department of a teaching district general hospital (excluding major head injury). Data were extracted from medica notes and from self-report at baseline, 3 months and 1 year. Most (61%) injuries were physically minor. At 1 year 45% reported major physical problems and 32% reported psychiatric consequences. Non-injury variables were the principal predictors of outcome. Outcome across a range of variables is considerably worse than would be expected from the nature of the physical injuries. There is a need for changes in clinical care and socio-legal policy to prevent, identify and treat distressing and disabling chronic problems.

Acquired growth hormone resistance in patients with chronic heart failure: implications for therapy with growth hormone

OBJECTIVES We aimed to determine whether growth hormone (GH) resistance is present in patients with chronic heart failure (CHF) and whether it may be linked to the biochemical response to GH treatment. BACKGROUND Acquired GH resistance is a feature of severe illness, in particular, cachexia. In patients with CHF, the response to GH therapy appears to be variable. METHODS Biochemical markers of the GH-insulin-like growth factor-I (IGF-I) axis were compared in 21 cachectic patients with CHF, 51 noncachectic patients and 26 healthy control subjects. In separate studies, the predictive value of baseline biochemical variables for the IGF-I response to GH treatment was analyzed. RESULTS Cachectic patients showed an increase of total GH and immunologically intact GH (p ≤ 0.0002) and a decrease of GH-binding protein (BP) (p = 0.005), IGF-BP3 (p = 0.01) and IGF-I (p = 0.06), compared with noncachectic patients. Similar changes were found when the cachectic group was compared with the control group. No differences were found between noncachectic patients and control subjects. Levels of GH-BP correlated with the IGF-I/GH ratio in all subgroups (all p ≤ 0.002). Baseline GH-BP levels were related to the increase of IGF-I levels in response to GH treatment in patients with CHF after 24 h (r = 0.83, p = 0.005; n = 9; study 2), 44 days (r = 0.52, p = 0.007; n = 25; study 3) and 96 days (r = 0.54, p = 0.006; n = 24; study 3). CONCLUSIONS Most cachectic and some noncachectic patients with CHF show features of acquired GH resistance. The principal predictors of the biochemical features of GH resistance and of the poor biochemical response to short-term and longer-term GH treatment are GH-BP plasma levels. The presence of GH resistance is potentially a major factor determining the response to GH therapy in patients with CHF.

Therapeutic options for acute myelogenous leukemia.

General therapeutic options for patients with acute myelogenous leukemia (AML) are reviewed and specific new therapies are described. Data in this review came from the published literature and the M. D. Anderson Cancer Center's acute leukemia database. Outcome following standard therapy of AML is so variable that is best to speak of a range of outcomes determined by various prognostic factors. Therapy can (and usually does) fail because of treatment-induced mortality or (more usually) resistance to therapy. Performance status and age are the principal predictors of early death, whereas cytogenetics, a history of abnormal blood counts, and MDR1 expression are predictors of resistance. Using this information, physicians can categorize patients into those in whom 1) standard therapy is indicated, 2) either standard or investigational therapy is appropriate, and 3) investigational therapy is indicated. The majority of even newly diagnosed patients belong to Group 3. The availability of allogeneic or autologous transplantation does not alter this conclusion. Investigational therapies have been developed that are directed against the CD33 surface antigen, the multidrug-resistant MDR1 protein, and other targets. Because of the number of new therapies clinical research in AML should emphasize pilot trials rather than traditionally large Phase III studies. Most patients with newly diagnosed AML should be offered investigational regimens.

Principal predictors

Principal predictors are linear combinations of variables from one set that efficiently describe the collective variability of those from a second set. Their defining eigenproblem is similar to that of canonical correlation analysis, and when the two sets are taken to be the same, principal predictors reduce to principal components. Within the context of a forecast model for the circulation in the Gulf of St. Lawrence, they are shown to be capable of providing a low-dimensional characterization of high-resolution model dynamics.

Principal predictors

Principal predictors

Factors associated with condom use in the male population of Mexico City.

Sexually transmitted diseases (STDs) are an important public health problem, due to their medical, social and economic repercussions. Therefore, more knowledge is needed about the sexual behaviour that promotes their spread, in order to improve control and prevention strategies. Our aim was to determine the frequency of male condom use associated with sexual behaviour factors, a history of and knowledge about STDs in a sample of the male population in Mexico City. During 1994 a cross-sectional epidemiological study was carried out, using multi-stage sampling with conglomerates, in 1377 men from 15 to 49 years old. The mean age was 34.5 years (SD 7.5 years). Mean age at first sexual relations was 17.7 years (SD 2.8 years). The global proportion of condom use during the last sexual relation was 24.6%; use according to type of female sex partner in the last year was 18.8% with regular partners and 62.5% with occasional partners. The principal predictors of male condom use, identified through statistical modelling, were: younger age (<25 years), middle and high education level (>9 years), middle and high socioeconomic level and type of sexual partners (occasional and regular). This population has risk factors for acquiring and transmitting some STDs, such as occasional sexual partners and a history of STDs. Characteristics which are important in relation to male condom use were identified, such as age (younger than 35), education (complete junior high school or more) and type of sexual partners (occasional and regular).

Factors Associated with Condom Use in the Male Population of Mexico City

Sexually transmitted diseases (STDs) are an important public health problem, due to their medical, social and economic repercussions. Therefore, more knowledge is needed about the sexual behaviour that promotes their spread, in order to improve control and prevention strategies. Our aim was to determine the frequency of male condom use associated with sexual behaviour factors, a history of and knowledge about STDs in a sample of the male population in Mexico City. During 1994 a cross-sectional epidemiological study was carried out, using multi-stage sampling with conglomerates, in 1377 men from 15 to 49 years old. The mean age was 34.5 years (SD 7.5 years). Mean age at first sexual relations was 17.7 years (SD 2.8 years). The global proportion of condom use during the last sexual relation was 24.6%; use according to type of female sex partner in the last year was 18.8% with regular partners and 62.5% with occasional partners. The principal predictors of male condom use, identified through statistical modelling, were: younger age (&lt;25 years), middle and high education level (&gt;9 years), middle and high socioeconomic level and type of sexual partners (occasional and regular). This population has risk factors for acquiring and transmitting some STDs, such as occasional sexual partners and a history of STDs. Characteristics which are important in relation to male condom use were identified, such as age (younger than 35), education (complete junior high school or more) and type of sexual partners (occasional and regular).

Principal Predictors and Efficiency in Small Second-Order Designs

Linear parametric functions affected by deleting or augmenting sets of design points are identified explicitly using principal components of the predictive dispersion at those points, offering fresh insight and significant computational savings. Leverages from regression diagnostics are seen to determine efficiencies due to augmenting or deleting single points. Eight small second-order designs are studied in detail with supporting numerical displays. Comparisons are drawn to other approaches from the literature.

Investigations into the accuracy of prediction of beef carcass composition using subcutaneous fat thickness and carcass weight II. Improving the accuracy of prediction

Attempts were made to improve the accuracy of prediction of carcass components in 68 steer carcasses using a subcutaneous fat thickness measurement (FTP 8) and hot side weight as the principal or sole predictors. When carcasses were divided into two weight ranges, prediction of the percentages of carcass fat (fat %) and muscle (muscle %) in the lighter group, using FTP 8, were almost as accurate (fat %: RSD, 1.83; R 2, 0.73; muscle %: RSD, 1.70; R 2, 0.47) as those given by multiple regression measurements made by advanced technologies. Prediction in the heavier weight group was unsatisfactory, featuring high RSDs and a low R 2. Because breed differences in prediction did not occur in the lighter group, a single prediction equation could be used for each carcass component. The use of fat thickness groups gave a similar result to that of weight groups. Once weight groups were used, curvilinear analysis did not improve the accuracy of prediction. In the lighter carcasses, the addition of hot side weight, eye muscle area and muscle score, singly or in combination, did not improve the accuracy of percentage predictions. In the heavier carcasses, the addition of hot side weight and eye muscle area was necessary to give prediction of a modest level of accuracy. For the prediction of the weights of carcass components, the addition of hot side weight to FTP 8 gave the most accurate prediction in light carcasses (fat weight: RSD, 1.60; R 2, 0.92; muscle weight: RSD, 2.08; R 2, 0.97). In the heavy carcasses, hot side weight and eye muscle area added to FTP 8 gave the most accurate prediction (fat weight: RSD, 4.40; R 2, 0.69; muscle weight: RSD, 3.73; R 2, 0.88). Because of the high level of variance explained, it is recommended that weights of carcass components be predicted, particularly in heavy carcasses.

A scoring system for the prediction of successful delivery in low-risk birthing units

To establish and test the effectiveness of a low-risk scoring system to predict obstetric outcome for the selection of women suitable for confinement in low-intervention units. Retrospective analyses were performed on data from 2900 women enrolled in the Western Australian Pregnancy Cohort Study and 1353 women managed at a midwifery-based birth center. A combination of the principal predictors of obstetric outcome, incorporating a previously published scoring system and various clinical features, was used to exclude high-risk cases at 18 weeks' and 36 weeks' gestation. Stepwise multivariate logistic regression analyses of the remaining pregnancies then produced a low-risk scoring system. This system predicted a 55% chance of an uncomplicated delivery in a midwifery-based setting after allocating 54% of women to the low-risk category. It predicted an 82% chance of an uncomplicated delivery in a primary medical care setting with the allocation of 84% of women as low risk. The results of this study suggest that adding induction and augmentation of labor, together with low pelvic instrumental delivery, to the treatment options in a low-intervention unit would raise the rate of successful confinement within the unit from 55% to 82%. Our scoring system now requires prospective evaluation to further assess its clinical value.

Deletion, augmentation and principal predictors

Effects of augmenting or deleting sets of design points are studied using principal components of the predictive dispersion at those points. The affected linear parameters are then given explicitly in terms of design points and coefficients defining the principal predictors. In addition to structural links, this approach offers computational advantages as well. The methods are illustrated numerically for second-order models using central composite designs.

Response of Femoral Arteries of Cholesterol-Fed Rabbits to Balloon Angioplasty with or without Laser: Emphasis on the Distribution of Foam Cells

Very little is known about the structural composition of the restenotic plaque in evolution. The responses of atherosclerotic femoral arteries of rabbits to balloon angioplasty (BA), thallium/holmium/chromium: YAG infrared laser angioplasty (LA), combined LA and BA, or no angioplasty were compared by blinded quantitative histomorphometry and angiography. The endothelium was injured by nitrogen/air desiccation, and the animals were fed a 2% cholesterol diet for 1 month prior to the angioplasty procedure. Animals were sacrificed 2 hr or 28 days after angioplasty by pressure perfusion with 10% formaldehyde (100 mm Hg), and arterial segments (4-5 cm) were excised bilaterally. The frequency of thrombus was greatest in arteries with LA. Arteries with combined LA and BA had the greatest initial gain in luminal diameter by angiography, but they also had the greatest reduction in luminal diameter from 2 hr to 28 days and the greatest cross-sectional area narrowing by plaque at 28 days. The principal component of the intimal plaques in all groups was fibrous tissue (approximately 90%), with the remainder consisting primarily of "foam cells." By multiple regression analysis, the strongest predictors of cross-sectional area narrowing were contiguity of foam cells between the intima and media, depth of the tear, percentage of foam cells in the plaque, and the intervention of LA followed by BA. The principal predictors of foam cells in the plaque, irrespective of treatment, were also cross-sectional area narrowing, contiguity of foam cells between plaque and media, and the depth of tear. It is suggested that a large proportion of the foam cells of the intima may be derived from foam cells of the media and adventitia rather than from the lumen. These observations may be of particular importance regarding angioplasty in young people where foam cells occupy a significantly greater proportion of the atherosclerotic plaque.

Cardiac Pathology in Patients with End-Stage Renal Disease Maintained on Hemodialysis

We report the spectrum of cardiovascular pathology found on autopsy examination in 106 consecutive patients with end-stage renal disease. Cardiovascular pathology was present in nearly all patients, and was the most frequent cause of death (36%), with acute myocardial infarction accounting for 15%. Particularly frequent pathologic findings were left ventricular hypertrophy, coronary and aortic atherosclerosis, pericarditis with effusion, myocardial fibrosis, and valvular dilatation. Cardiovascular death rate was higher during the first year than after the fifth year of dialysis. Nearly all patients had a history of hypertension. The nature of the underlying cause of renal failure and pre-existing cardiovascular disease, specifically diabetes mellitus and hypertension, were the principal predictors of cardiovascular mortality rather than maintenance hemodialysis therapy per se.

Influence of low-flow infusion and magnesium on tissue necrosis during regional ischemia in the canine myocardium.

Passive intracoronary perfusion of therapeutic agents has been used in the clinical setting to attenuate the effects of brief episodes of myocardial ischemia. The objective of this study was to assess the effects of low-flow coronary infusion with or without Mg2+ on tissue necrosis and cardiac hemodynamics after prolonged regional ischemia. In 33 anesthetized dogs (5 excluded during study), the left anterior descending coronary artery was occluded for 6 h. Dogs were assigned to three groups: the first group (n = 8) was subjected to 6 h coronary occlusion without low-flow perfusion (controls), the second group (n = 10) received a low-flow coronary infusion of Ringer's lactate (Mg(2+)-free), and the third group (n = 10) received a low-flow coronary infusion of Ringer's lactate plus Mg2+ sulfate (15 mM). Tissue necrosis was evaluated using tetrazolium staining and was normalized to the principal baseline predictors of infarct size including anatomic risk zone (microsphere autoradiography) and coronary collateral flow. In control hearts, infarct size comprised 51.1 +/- 4.1% of the risk zone (40.8 +/- 5.1% left ventricular cross-sectional area (LV)). In the Mg(2+)-free and Mg2+ groups, risk zone size was 17.3 +/- 2.2 and 16.8 +/- 1.8% LV (p < 0.05 vs. controls), while infarct size was 23.1 +/- 3.1 and 24.9 +/- 8.1% (p < 0.05 vs. controls), respectively. Coronary collateral flow in the endocardium was similar for all of the experimental groups; however, hearts subjected to ischemia with low-flow perfusion of Ringer's lactate demonstrated significantly higher epicardial coronary collateral flow levels compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Midfacial fractures and the eye: the development of a system for detecting patients at risk of eye injury

Maxillofacial trauma is often complicated by injury to the eye. Such injuries may be difficult to detect and may therefore be missed. Detailed ophthalmic examinations were carried out prospectively on 363 patients who had sustained midfacial fractures. Fifty four parameters comprising maxillofacial, radiological and ophthalmic data were recorded and coded for each patient. All encoded data were divided into predictors (the data potentially available to the maxillofacial surgeon) and outcome (the data potentially available to the ophthalmologist). Statistical methods of regression, and the analysis of contingency tables, led to the identification of the principal predictors indicative of underlying ophthalmic injury and thence to a scoring system which predicts the severity of such injuries. Impaired visual acuity is the principal predictor and when employed alone gives a sensitivity value of 811%. Pure blow-out fracture or comminuted facial fracture, double vision and amnesia emerged as additional factors which yielded an efficient scoring system with a sensitivity of 89% and specificity of 90% for the population upon which it was based. A score sheet is provided in the paper. These predictors can be remembered from the acronym Blow-out fracture, Acuity, Diplopia, Amnesia, Comminuted Trauma. As many such injuries result from a BAD ACT, it is easily remembered. This scoring system requires to be tested upon a new population of individuals in order to determine its efficacy.

Predisposing and causative factors in childhood epilepsy.

We review information from large studies of defined populations, examining the role of known factors and especially of prenatal and perinatal factors in contributing to nonfebrile seizure disorders of early childhood. We depend especially, but not exclusively, on the recently completed analyses from the Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the NCPP. About 4% of children in the NCPP who had at least one nonfebrile nonsymptomatic seizure by the age of 7 years had a previous seizure during acute neurologic illness, such as meningitis or during the acute illness after trauma. Many such seizures should potentially be preventable. Of children with seizures, 10% had had a neonatal seizure and 13% had had a febrile seizure. Among the hundreds of prenatal and perinatal factors explored as predictors of childhood seizure disorders, the principal predictors identified were congenital malformations of the fetus, cerebral and noncerebral; family history of certain neurologic disorders; and neonatal seizures. In agreement with the British National Child Development Study, labor and delivery factors in the NCPP appeared to contribute very little to childhood seizure disorders. Maldevelopment, rather than damage at birth to an initially intact nervous system, appeared to be the more common mechanism. Most seizure disorders of early childhood remained unexplained by the large set of prenatal and perinatal characteristics examined.