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The Behavioural Status Index: testing a social risk assessment model in a high security forensic setting.

The Behavioural Status Index model suggests that 'social risk' tends to vary inversely with an individual's insight and capacity to perform key communication and social skills. The aim of this study was to describe emergent trends in data related to the risk, insight, and communication and social skills subscales used in the model. Data were collected from 503 patients in two high security mental health hospitals. Although a distinct factorial structure emerged suggesting groupings of behaviours, results provide little support for the overall model proposed.

Dangerous Behavior↗

Cerebral palsy: evaluation of a model of risk.

The purpose of this study was to assess a model of risk for cerebral palsy (CP) in preschool children. The research was structured as a retrospective case-control study in which cases (n = 112) were children with CP while controls (n = 153) were either friend referrals or population-based. Data were collected via structured telephone interviews. While significant associations with CP were found on univariate analyses for a number of variables, only four variables--birth weight/gestational age, 5-min APGAR, medication for miscarriage, and urinary tract infection during pregnancy--were found predictive in multivariate analysis. These variables accounted for 36% of the log-likelihood explained by the model.

Birth Weight↗

Methods to assess performance of models estimating risk of death in intensive care patients: a review.

Models that estimate the probability of death of intensive care unit patients can be used to stratify patients according to the severity of their condition and to control for casemix and severity of illness. These models have been used for risk adjustment in quality monitoring, administration, management and research and as an aid to clinical decision making. Models such as the Mortality Prediction Model family, SAPS II, APACHE II, APACHE III and the organ system failure models provide estimates of the probability of in-hospital death of ICU patients. This review examines methods to assess the performance of these models. The key attributes of a model are discrimination (the accuracy of the ranking in order of probability of death) and calibration (the extent to which the model's prediction of probability of death reflects the true risk of death). These attributes should be assessed in existing models that predict the probability of patient mortality, and in any subsequent model that is developed for the purposes of estimating these probabilities. The literature contains a range of approaches for assessment which are reviewed and a survey of the methodologies used in studies of intensive care mortality models is presented. The systematic approach used by Standards for Reporting Diagnostic Accuracy provides a framework to incorporate these theoretical considerations of model assessment and recommendations are made for evaluation and presentation of the performance of models that estimate the probability of death of intensive care patients.

APACHE↗

Validation of risk adjustment models for in-hospital percutaneous transluminal coronary angioplasty mortality on an independent data set.

OBJECTIVES: We sought to validate recently proposed risk adjustment models for in-hospital percutaneous transluminal coronary angioplasty (PTCA) mortality on an independent data set of high risk patients undergoing PTCA. BACKGROUND: Risk adjustment models for PTCA mortality have recently been reported, but external validation on independent data sets and on high risk patient groups is lacking. METHODS: Between July 1, 1994 and June 1, 1996, 1,476 consecutive procedures were performed on a high risk patient group characterized by a high incidence of cardiogenic shock (3.3%) and acute myocardial infarction (14.3%). Predictors of in-hospital mortality were identified using multivariate logistic regression analysis. Two external models of in-hospital mortality, one developed by the Northern New England Cardiovascular Disease Study Group (model NNE) and the other by the Cleveland Clinic (model CC), were compared using receiver operating characteristic (ROC) curve analysis. RESULTS: In this patient group, an overall in-hospital mortality rate of 3.4% was observed. Multivariate regression analysis identified risk factors for death in the hospital that were similar to the risk factors identified by the two external models. When fitted to the data set, both external models had an area under the ROC curve >0.85, indicating overall excellent model discrimination, and both models were accurate in predicting mortality in different patient subgroups. There was a trend toward a greater ability to predict mortality for model NNE as compared with model CC, but the difference was not significant. CONCLUSIONS: Predictive models for PTCA mortality yield comparable results when applied to patient groups other than the one on which the original model was developed. The accuracy of the two models tested in adjusting for the relatively high mortality rate observed in this patient group supports their application in quality assessment or quality improvement efforts.

Aged↗

Predicting medical and surgical complications of carotid endarterectomy: comparing the risk indexes.

BACKGROUND: Several generic cardiac risk assessment tools predict perioperative cardiac complications, but their ability to predict a broader range of medical, neurologic, and surgical complications is unknown. METHODS: A multicenter retrospective observational cohort study of 1998 patients undergoing carotid endarterectomy (CEA). Complications within 30 days of surgery were assessed by medical record review, including death or nonfatal stroke and cardiac, noncardiac medical, minor neurologic, and wound complications. Logistic regression and receiver operating characteristic curve analyses assessed the predictive abilities of the Goldman, Detsky, Revised Cardiac Risk, and American Society of Anesthesiologists indexes and of 2 CEA-specific risk models (the Halm and Tu scores). RESULTS: Death or stroke occurred in 3.2% of patients, cardiac complications in 4.0%, noncardiac medical complications in 3.2%, minor neurologic complications in 6.9%, and wound complications in 6.0%. All risk models (except the Tu score) significantly predicted cardiac complications equally well (P<.05). All 6 risk models were equivalent in predicting noncardiac medical complications. Only the Revised Cardiac Risk Index and the 2 CEA-specific risk models (Halm and Tu scores) predicted death or stroke and minor neurologic and wound complications. The Halm score was superior in predicting death or stroke compared with the Tu score and the Revised Cardiac Risk Index (area under the receiver operating characteristic curve, 0.72 vs 0.62 and 0.61, respectively; P<.05). Patients with cardiac, noncardiac medical, minor neurologic, or wound complications had 3- to 16-fold increased odds of death or stroke. CONCLUSION: The Halm score CEA-specific risk model and the generic Revised Cardiac Risk Index predicted a broad range of medical, neurologic, and surgical complications following CEA.

Aged↗

The Society of Thoracic Surgeons National Cardiac Surgery Database: current risk assessment.

BACKGROUND: The Society of Thoracic Surgeons National Cardiac Surgery Database has recently completed gathering patient data from 1990 through 1994. Using information from more than 300,000 patients undergoing isolated coronary artery bypass grafting in this period, new risk models of operative mortality were developed. METHODS: Logistic regression analysis was used to develop a risk model for each calendar year. A standard "training set/test set" approach was used for each model. RESULTS: Five validation techniques were used to evaluate the reliability of the risk models. All models were found to predict operative mortality with good accuracy in this population. CONCLUSIONS: The new risk models for isolated coronary artery bypass operations serve as reliable predictors of operative mortality for the most recent harvest of patient data from The Society of Thoracic Surgeons National Cardiac Surgery Database.

Coronary Artery Bypass↗

Carcinogenesis models for risk assessment.

This article provides an overview of different types of carcinogenesis models and discusses their use for risk assessment. One class of model, the multistage model, is especially suited for risk assessment purposes because it uses biological information about the process of carcinogenesis and the quantities of interest, such as time to tumour and number and size distribution of premalignant tumours, can be derived explicitly, allowing for standard statistical techniques to be used. The mathematical methods necessary for the treatment of multistage models are developed and the application of multistage models in risk assessment is discussed.

Carcinogens↗

The development of risk assessment models for carpal tunnel syndrome: a case-referent study.

The present study developed risk assessment models for carpal tunnel syndrome (CTS) which can provide information of the likelihood of developing CTS for an individual having certain personal characteristics and occupational risks. A case-referent study was conducted consisting of two case groups and one referent group: (1) 22 work-related CTS patients (W-CTS), (2) 25 non-work related CTS patients (NW-CTS), and (3) 50 healthy workers (HEALTHY) having had no CTS history. The classification of CTS patients into one of the case groups was determined according to the type of insurance covering their medical costs. Personal characteristics, psychosocial stresses at work, and physical work conditions were surveyed by using a questionnaire tailor-designed to CTS (reliability of each scale > or = 0.7). By contrasting the risk information of each case group to that of the referent group, three logistic regression models were developed: W-CTS/HEALTHY, NW-CTS/HEALTHY, and C-CTS/HEALTHY (C-CTS, the combined group of W-CTS and NW-CTS). ROC analysis indicated that the models have satisfactory discriminability (d' = 1.91 to 2.51) and high classification accuracy (overall accuracy = 83-89%). Both W-CTS/HEALTHY and C-CTS/HEALTHY include personal and physical factors, while NW-CTS/HEALTHY involves only personal factors. This suggests that the injury causation of NW-CTS patients should be attributable mainly to their 'high' personal susceptibility to the disorder rather than exposure to adverse work conditions, while that of W-CTS patients be attributable to improper work conditions and CTS-prone personal characteristics in combination.

Carpal Tunnel Syndrome↗

Risk assessment and early outcome following the Norwood procedure for hypoplastic left heart syndrome.

BACKGROUND: This study was undertaken to identify risk factors for early mortality following the Norwood procedure for hypoplastic left heart syndrome (HLHS) and develop a predictive risk model to monitor clinical performance. METHODS AND RESULTS: Between December 1992 and June 2004, 333 patients with HLHS underwent a Norwood procedure at a single institution. The early mortality was 29% (n=95). Estimated early mortality improved progressively and was 10% at the end of the series. Multivariable analysis identified that body surface area at operation, size of the ascending aorta, preoperative right ventricular function and source of pulmonary blood flow established at operation were risk factors for early mortality (P<0.05). These variables were included in a preoperative risk model. The duration of cardiopulmonary support was an independent risk factor, which was included in a separate operative risk model. The performance of the risk models was evaluated by goodness-of-fit analyses, using the Hosmer-Lemeshow test and receiver operating characteristic (ROC) curve. Both models were well calibrated across all deciles (P=0.64, P=0.77) and discriminated moderately well. The area under the ROC curve was 0.71 for Model 1 and 0.75 for Model 2. Risk adjustment broadly accounted for the variation in early mortality observed during this series. CONCLUSIONS: Patient-related and predetermined operative variables have a major influence on the early outcome following the Norwood procedure for HLHS. The identification of these risk factors allows the risk of early mortality to be calculated. This information could be applied as part of a risk-adjusted performance-monitoring system to enable early identification of meaningful changes in practice.

Aorta↗

[Prediction value for operative mortality of four different coronary artery bypass graft risk stratification models in Chinese patients].

OBJECTIVE: To assess the prognostic accuracy for operative mortality of 4 different risk stratification models in Chinese patients underwent (coronary artery bypass graft) CABG. METHODS: Between 2002 and 2003, all patients undergoing CABG in our institution were prospectively scored for operative mortality using Parsonnet, EuroSCORE, Cleveland and OPR scoring systems and operative mortality was registered. Operative mortality is defined as postoperative death of any cause during hospitalization. Calibration was estimated using the Hosmer-Lemeshow goodness-of-fit test. Discrimination was evaluated using receiver operating characteristic (ROC) curves and area under a ROC curve (AUC). RESULTS: Follow-up was able to be completed in 2251 prospectively scored patients. Registered operative mortality was 1.87% (42/2251). The overall expected mortality calculated by Parsonnet, EuroSCORE, Cleveland and OPR scoring systems were 5.78%, 2.82%, 3.30% and 1.65%, respectively. The actual operative mortality was within the range of 95% confidence interval of OPR model and the other 3 predicted significantly higher operative mortality. Among the four risk scores, Calibration was good in OPR model (chi(2) = 4.842, P = 20.182) and poor in other 3 models (P < 0.001) while discrimination was acceptable in Parsonnet, Cleveland and OPR scoring systems (AUC: 0.711, 0.754, 0.757, respectively) and excellent in EuroSCORE scoring system (0.813). CONCLUSION: For Chinese patients undergoing CABG, OPR scoring system best predicted the operative mortality. All systems could be used to discriminate operative mortality for individual patient.

China↗

A Bayesian approach to measurement error problems in epidemiology using conditional independence models.

Risk factors used in epidemiology are often measured with error which can seriously affect the assessment of the relation between risk factors and disease outcome. In this paper, a Bayesian perspective on measurement error problems in epidemiology is taken and it is shown how the information available in this setting can be structured in terms of conditional independence models. The modeling of common designs used in the presence of measurement error (validation group, repeated measures, ancillary data) is described. The authors indicate how Bayesian estimation can be carried out in these settings using Gibbs sampling, a sampling technique which is being increasingly referred to in statistical and biomedical applications. The method is illustrated by analyzing a design with two measuring instruments and no validation group.

Bayes Theorem↗

Short-term and 5-year outcome after primary isolated coronary artery bypass graft surgery: results of risk stratification in a bilocation center.

OBJECTIVE: We retrospectively investigated the short and mid-term outcome of non-emergent primary isolated coronary artery bypass graft (CABG) surgery in relation to risk stratification in the fully equipped university location (FE) and the low volume, limited facility location (LVLF) of our department. METHODS: Between September 1995 and December 1996, 832 patients were referred to our department to undergo a primary isolated CABG operation. The surgical team selected 482 patients (58%) as being at low-risk. These were treated in the LVLF hospital. The other 350 patients with mixed-risk were treated in the FE hospital. The selection consisted primarily of exclusion of patients with moderate or poor left ventricular function, severe COPD or renal impairment, from surgery in the LVLF location. Finally, the prognostic value of the EuroSCORE and the Parsonnet score was tested on our patient population. RESULTS: Overall in-hospital mortality was 1.6% (13 patients). One patient died in the LVLF group (0.2%) and 12 patients (3.4%) in the FE group. LVLF patients experienced less complications during the hospital period compared to the FE patients (5 versus 21%; P=0.0001). The Parsonnet risk model and the EuroSCORE risk model showed both a good relation with in-hospital mortality. After discharge, an increased risk of late mortality was observed up to 1 year postoperative in the FE group compared to the LVLF group (2.7 versus 0.5%; P=0.01). Risk factors for 5-year mortality were pre-operative renal impairment (blood creatinine >150 micromol/l) (hazard ratio (HR): 2.8; 95% confidence interval (CI): 1.4-5.5), diabetes (HR: 2.1; 95% CI: 1.3-3.5), impaired LVEF (HR: 1.9; 95% CI: 1.2-3.0), COPD (HR: 1.9; 95% CI: 1.1-3.5) and older age (HR: 1.07 per year; 95% CI: 1.01-1.10). Lipid-lowering therapy was a predictor of lower mortality at 5-years (HR: 0.5; 95% CI: 0.4-0.9). CONCLUSION: By careful decision making, selection of low-risk patients for a low volume and limited facility location resulted in excellent in-hospital survival with very low complication rates.

Adult↗

Postoperative nausea and vomiting: a review of current literature.

INTRODUCTION: Postoperative nausea and vomiting (PONV) is one of the commonest complaints following anaesthesia, and can result in morbidity like wound dehiscence, bleeding, pulmonary aspiration of gastric contents, fluid and electrolyte disturbances, delayed hospital discharge, unexpected hospital admission, and decreased patient satisfaction. METHOD: A literature search was done on the Medline and relevant articles chosen. RESULTS: Despite the vast amount of research done in this field and the variety of antiemetic drugs available, PONV still has a high incidence. Many factors are associated with PONV. Quantifying the relative impact of risk factors on PONV has resulted in the development of risk models, which can stratify risk categories and hence allow the anaesthetist to identify those patients at higher risk for PONV. The management of PONV requires a multi-modal approach which can include the use of less emetogenic anaesthetic techniques, balanced analgesia, appropriate intravenous hydration, the use of pharmacotherapy and possibly non-pharmacologic methods. CONCLUSIONS: The use of risk models facilitates the judicious use of pharmacotherapy to ameliorate PONV especially in the high-risk patient and may lead to a more cost effective and efficient means of managing PONV.

Antiemetics↗

The prognostic significance of ubiquitination-related genes in multiple myeloma by bioinformatics analysis.

BACKGROUND: Immunoregulatory drugs regulate the ubiquitin-proteasome system, which is the main treatment for multiple myeloma (MM) at present. In this study, bioinformatics analysis was used to construct the risk model and evaluate the prognostic value of ubiquitination-related genes in MM. METHODS AND RESULTS: The data on ubiquitination-related genes and MM samples were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The consistent cluster analysis and ESTIMATE algorithm were used to create distinct clusters. The MM prognostic risk model was constructed through single-factor and multiple-factor analysis. The ROC curve was plotted to compare the survival difference between high- and low-risk groups. The nomogram was used to validate the predictive capability of the risk model. A total of 87 ubiquitination-related genes were obtained, with 47 genes showing high expression in the MM group. According to the consistent cluster analysis, 4 clusters were determined. The immune infiltration, survival, and prognosis differed significantly among the 4 clusters. The tumor purity was higher in clusters 1 and 3 than in clusters 2 and 4, while the immune score and stromal score were lower in clusters 1 and 3. The proportion of B cells memory, plasma cells, and T cells CD4 na&#xef;ve was the lowest in cluster 4. The model genes KLHL24, HERC6, USP3, TNIP1, and CISH were highly expressed in the high-risk group. AICAr and BMS.754,807 exhibited higher drug sensitivity in the low-risk group, whereas Bleomycin showed higher drug sensitivity in the high-risk group. The nomogram of the risk model demonstrated good efficacy in predicting the survival of MM patients using TCGA and GEO datasets. CONCLUSIONS: The risk model constructed by ubiquitination-related genes can be effectively used to predict the prognosis of MM patients. KLHL24, HERC6, USP3, TNIP1, and CISH genes in MM warrant further investigation as therapeutic targets and to combat drug resistance.

Humans↗

Cariogram--a multifactorial risk assessment model for a multifactorial disease.

This paper reviews some common methods for the assessment of caries risk. It also describes a new way of illustrating the caries risk profile of an individual, the Cariogram. Past caries experience and socioeconomic factors are often used for prediction of caries. As prediction models, the methods are simple, inexpensive and fast. However, they are not risk models, as they do not specify which particular risk factors are operating. Various biological factors can be used for risk assessment. Common ones are bacteria, diet and host factors. Taken separately, these biological factors often have limited predictive values. Socioeconomic factors often have a heavy impact on the biological factors as they can explain why an individual, for example, has a cariogenic diet or neglects oral hygiene. The biological factors are the immediate cause of the cavities. Caries experience is an illustration of how the host copes up with the biological activity. To facilitate the interpretation of biological data, the Cariogram was developed. It is a computer program showing a graphical picture that illustrates a possible overall caries risk scenario. The program contains an algorithm that presents a 'weighted' analysis of the input data, mainly biological factors. It expresses as to what extent different etiological factors of caries affect caries risk. The Cariogram identifies the caries risk factors for the individual and provides examples of preventive and treatment strategies to the clinician.

Aged↗

A biopsychobehavioral model of risk of severe hypoglycemia.

Severe hypoglycemia (SH) is a significant problem for many patients with type I diabetes and presents a major barrier to optimal diabetes control. A critical task facing diabetes research is to understand, predict, and reduce the risk of SH in insulin-treated patients. The purpose of this article is to propose a biopsychobehavioral model of SH risk that integrates and extends previously proposed models. Current biological and psychological models of SH risk, which focus on hormonal counterregulation and symptom awareness, are reviewed. The limitations of these models are also discussed, including their failure to recognize important psychological and behavioral processes that contribute to SH risk. Specifically, the biopsychobehavioral model includes patients' decision-making, judgment, and behavioral responses as significant predictors of SH risk. The proposed model is comprised of seven steps: 1) physiological and behavioral precursors to low blood glucose (BG), 2) low BG occurrence, 3) hormonal and neurological responses to low BG, 4) awareness of symptoms caused by hormonal and neurological changes, 5) detection of low BG, 6) decision-making and judgment, and 7) behavioral response. The model has several advantages, including the ability to mathematically calculate the transitional probabilities from each step to the next as well as the ability to describe SH risk in both hypoglycemia-aware and hypoglycemia-unaware patients. Research findings supporting the biopsychobehavioral model are presented, and its empirical and clinical implications are discussed.

Behavior↗

Determinants of maternity length of stay: a Gamma mixture risk-adjusted model.

With obstetrical delivery being the most frequent cause for hospital admissions, it is important to determine health- and patient-related characteristics affecting maternity length of stay (LOS). Although the average inpatient LOS has decreased steadily over the years, the issue of the appropriate LOS after delivery is complex and hotly debated, especially since the introduction of the mandatory minimum-stay legislation in the USA. The purpose of this paper is to identity factors associated with maternity LOS and to model variations in LOS. A Gamma mixture risk-adjusted model is proposed in order to analyze heterogeneity of maternity LOS within obstetrical Diagnosis Related Groups (DRGs). The determination of pertinent factors would benefit hospital administrators and clinicians to manage LOS and expenditures efficiently.

Diagnosis-Related Groups↗

Risk factors for post-ERCP pancreatitis: a prospective multicenter study.

OBJECTIVES: Pancreatitis is the most common and serious complication of diagnostic and therapeutic ERCP. The aim of this study is to examine the potential patient- and procedure-related risk factors for post-ERCP pancreatitis in a prospective multicenter study. METHODS: A 160-variable database was prospectively collected by a defined protocol on patients undergoing diagnostic or therapeutic ERCP at 15 centers in the Midwest Pancreaticobiliary Group and participating in a randomized controlled study evaluating whether prophylactic corticosteroids will reduce the incidence of post-ERCP pancreatitis. Data were collected prior to the procedure, at the time of procedure, and 24-72 h after discharge. Post-ERCP pancreatitis was diagnosed and its severity graded according to consensus criteria. RESULTS: Of the 1,115 patients enrolled, diagnostic ERCP with or without sphincter of Oddi manometry (SOM) was performed in 536 (48.1%) and therapeutic ERCP in 579 (51.9%). Suspected sphincter of Oddi dysfunction (SOD) was the indication for the ERCP in 378 patients (33.9%). Pancreatitis developed in 168 patients (15.1%) and was graded mild in 112 (10%), moderate in 45 (4%), and severe in 11(1%). There was no difference in the incidence of pancreatitis or the frequency of investigated potential pancreatitis risk factors between the corticosteroid and placebo groups. By univariate analysis, the incidence of post-ERCP pancreatitis was significantly higher in 19 of 30 investigated variables. In the multivariate risk model, significant risk factors with adjusted odds ratios (OR) were: minor papilla sphincterotomy (OR: 3.8), suspected SOD (OR: 2.6), history of post-ERCP pancreatitis (OR: 2.0), age <60 yr (OR: 1.6), > or =2 contrast injections into the pancreatic duct (OR: 1.5), and trainee involvement (OR: 1.5). Female gender, history of recurrent idiopathic pancreatitis, pancreas divisum, SOM, difficult cannulation, and major papilla sphincterotomy (either biliary or pancreatic) were not multivariate risk factors for post-ERCP pancreatitis. CONCLUSION: This study emphasizes the role of patient factors (age, SOD, prior history of post-ERCP pancreatitis) and technical factors (number of PD injections, minor papilla sphincterotomy, and operator experience) as the determining high-risk predictors for post-ERCP pancreatitis.

Adult↗