paola berchialla | Università degli Studi di Torino (original) (raw)

Papers by paola berchialla

The oncologist, Jan 1, 2012

Background. Human epidermal growth factor receptor (HER)-2 testing in patients with operable brea... more Background. Human epidermal growth factor receptor (HER)-2 testing in patients with operable breast cancer is aimed at identifying candidates for adjuvant anti-HER-2 treatment. However, commonly defined "HER-2 ؊ " tumors express variable levels of the HER-2 protein, which can influence prognosis. We compared the clinical outcomes of operable breast cancer patients stratified according to a common HER-2 testing algorithm.

European journal of endocrinology / European Federation of Endocrine Societies, Jan 1, 2012

Journal of endocrinological investigation, Jan 1, 2012

In the literature, few studies analyze the effect of GH therapy on height, preferring a more indi... more In the literature, few studies analyze the effect of GH therapy on height, preferring a more indirect approach, where factors influencing the total pubertal and pre-pubertal growth in GH-deficient patients are evaluated and subsequently used to estimate the overall effect at the end of the therapy; unfortunately, this approach does not quantify the real growth gain in treated patients. Using a non-parametric Empirical Bayes approach, our study analyzes the growth response to GH treatment in a homogeneous cohort of 317 patients with pituitary GH deficiency who were enrolled during their pre-pubertal stage in the GH Piedmont Registry (Italy), between January 2000-October 2008, and have at least 2 yr of follow-up. To estimate the growth curve for males and females, a non-parametric regression model was fitted, applying Empirical Bayes techniques. A validation of the model was also performed. Improvement was evident in both genders, since both males and females mean growth curve, which started below the 3rd percentile at the beginning of the therapy, reached the 10th percentile of the Tanner curve at the end of observation (17 yr old for males and 14 yr old for females); the estimation procedure achieved a good precision. The methodological approach allows for fitting a model able to evaluate longitudinally the response to GH treatment, by means of estimating the overall growth curve, even in presence of sparse information about children heights.

Journal of human genetics, Jan 1, 2011

International journal of environmental health research, Jan 1, 2012

Cerano is a municipality of the Province of Novara (North-West Italy). To assess the morbidity as... more Cerano is a municipality of the Province of Novara (North-West Italy). To assess the morbidity associated to its proximity to a petrochemical plant, standardized incidence ratios (SIRs) of oncological pathologies in the period 2003-2009 were calculated based on age-sex specific rates for the district of the Local Health Authority of Novara (ASL13) and the main regional city of Turin. For all cancers combined, men showed a significant higher risk (SIR: 1.21; 95% CI: 1.02-1.40) compared to the ASL13 population; significantly lower risks for both men and women were observed in comparison to the Turin population. Among women, a significant excess of mesothelioma cancers was reported; a significantly higher risk for lympho-haematopoietic pathologies was also observed compared to the Turin population only. Several other cancers have significantly lower rates in Cerano for both men and women. Despite some studies&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; limitations, these findings could suggest potential chemical risk factors and need further investigation.

Journal of Evaluation in …, Jan 1, 2012

Background Identification of key factors associated with the risk of adverse cardiovascular event... more Background Identification of key factors associated with the risk of adverse cardiovascular events and quantification of this risk using multivariable prediction algorithms are among the major advances made in preventive cardiology and cardiovascular epidemiology. Methods In the present paper, we examined clinical predictors of adverse cardiovascular events among 228 individuals with symptoms suggestive of coronary artery disease (CAD) undergoing functional (stress echocardiography) and anatomical (coronary angiography) assessment of CAD. Particularly, we evaluate the possibility to integrate simple measures that have known prognostic value and more recently discovered predictors of risk, such as stress-related ventricular function data and angiographic data, in a unique model implementing a Bayesian network (BN). Moreover, we compared the performance of BN and the covariates hierarchy with those obtained from logistic regression model and from a set of alternative tools becoming popular in various clinical settings, including random forest classification tree analysis, artificial neural networks and support vector machine. Results Network graph and results coming from sensitivity analysis, where variables are ranked according to the gain they provided in variance reduction, seem have an easily intuitive lecture: variables that are measure of ventricular disfunction or of the extent of CAD show a greater impact in predicting event. On the other hand, anamnestic data such as diabetes, dyslipidaemia, hypertension, smoke habits, which are related to the outcome throughout a process of intermediate variables, per se have a small role in outcome prediction. BNs are able to explain a relevant part of variance (70%) and have discrimination ability superior or comparable with those to random forest classification tree analysis, artificial neural networks and support vector machine. Discussion Despite the complexity of interactions, model obtained implementing a BN seems to be able to adequately describe the relationships existing among the analysed variables. BN, being able to predict scenarios in which new variables can be incorporated as health process evolves, can measure individual's risks for adverse cardiovascular events, providing a permanent second opinion to the medical practitioner and assisting diagnostic and therapeutic process.

Journal of evaluation …, Jan 1, 2011

Aim A relative excess of fat in the upper body region has been proven to be associated with incre... more Aim A relative excess of fat in the upper body region has been proven to be associated with increased coronary artery disease (CAD) risk. Dual-energy X-ray absorptiometry (DXA) is probably the most accurate and precise method available to study fat regional distribution and to directly measure total body fat and lean soft tissue mass. However, while several studies have investigated the abilities of obesity anthropometric measures in predicting CAD, only few studies have evaluated DXA as CAD predictor; particularly, a comparison between a model including information coming from anthropometric measurements and a model in which fat is precisely measured by DXA, is still lacking. In order to verify if CAD severity, as measured by Gensini score, is better predicted when a prognostic model includes DXA measurements rather than anthropometric measures, we compared performance obtained by two Bayesian Networks (BNs) including standard anthropometric measures and DXA, respectively. Methods Data come from 58 consecutive patients, 79% of them having suspected and 21% known CAD. Two BNs were implemented: input variables include anamnestic information, biochemical data and obesity measures. In the first model (BN1) obesity was measured by body mass index and waist-to-hip ratio, while in the second one (BN2) it is quantified by DXA-derived parameters. Results Network graphs and results coming from sensitivity analysis show that in both models lipoproteins and biomarkers of inflammation act as proximal node, while obesity (independently of the chosen measure) appears to be a distal node acting by the intermediation of other variables. Both models show high predictive abilities, the mean percentage classification errors being, respectively, 14.13 and 18.87. Conclusions In our study, the BN predictive ability is slightly superior when obesity is measured using anthropometric data instead of DXA measurements. The reason probably relies on the fact that in the BN the obesity role in predicting CAD is mediated by the action of other factors that appear to be more directly influencing the outcome. Thus, the necessity to dispose of a perfect measure becomes less compulsory and the huge effort to precisely estimate body composition with complex methods as DXA could be avoided when using expert system such as BN as predictive tool.

Journal of evaluation …, Jan 1, 2010

Mortality prediction models using logistic regression analysis play a pivotal role in intensive c... more Mortality prediction models using logistic regression analysis play a pivotal role in intensive care quality evaluation, allowing a hospital's performance to be compared with a standard. However, when a difference between predicted and observed mortality exists, that is, the numerator of the Variable Life Adjusted Display (VLAD) score, the investigation for a possible explanation could be arduous. In this article we tested the ability of Bayesian Network (BN) to identify factors determining the negative discrepancy between expected and actual outcomes recorded in four Italian intensive care units (ICUs). Methods A BN was implemented to predict the extent of the expected-observed distance quantified by the VLAD score. BN performance was compared with those of a set of tools including Linear Model, Random Forest Regression Tree analysis, Artificial Neural Networks and Support Vector Machine. Results BN allows the identification of critical areas responsible for bad performance. Compared with other techniques, BN always explains a higher variance percentage and it shows similar or superior discrimination ability. Conclusions BN, being able to guide interpretation of covariates role by means of a graphic representation of relationships, confirms its utility particularly where many interactions between predictors exist and when a coherent set of theories regarding which variables are related and how is not available.

American Journal of Industrial Medicine, Jan 1, 2009

Background There are very few published studies evaluating the impact of safety and health traini... more Background There are very few published studies evaluating the impact of safety and health training on injury outcomes in the construction industry. The aim of this study was to assess the impact of the training program on injury rates at a major railway construction project. Methods The population consisted of 2,795 workers involved in a safety training program at the construction sites of the high-speed railway line Torino-Novara. Two types of analyses were carried out in order to assess the effectiveness of the training program in reducing the number of injuries: (i) a pre-post analysis, which took into account the fact that workers were enrolled at different times and the training intervention did not occur at the same time for all subjects; (ii) an interrupted time-series model, which corrected for the time trend and considered the autocorrelation between individual observations. Results Twenty-nine percent of workers who spent at least 1 day at the construction sites attended at least one training module. Pre-post analysis: At the end of the training program, the incidence of occupational injuries had fallen by 16% after the basic training module and by 25% following the specific modules. Time-series model: Training led to a 6% reduction in injury rates, which was not statistically significant. Conclusions The training program that was implemented had a moderately positive impact on the health of workers. Further studies are being conducted to obtain a more complete assessment of the actual effectiveness of the program in reducing the incidence of injuries. Am. J. Ind. Med. 52:965-972,

Statistics in …, Jan 1, 2009

Many outcome variables in oral research are characterized by positive values and heavy skewness i... more Many outcome variables in oral research are characterized by positive values and heavy skewness in the right tail. Examples are provided by many distributions of dental variables such as DMF (decayed, missing, filled teeth) scores, oral health impact profile score, gingival index scores, and microbiologic counts. Moreover, heterogeneity in data arises when more than one tooth is studied for each patient, due to the clusterization.Over the past decade, linear mixed models (LMEs) have become a common statistical tool to account for within-subject correlation in data with repeated measures. When a normal error is reasonably assumed, estimates of LMEs are supported by many statistical packages. Such is not the case for skewed data, where generalized linear mixed models (GLMMs) are required. However, the current software available supports only special cases of GLMMs or relies on crude Laplace-type approximation of integrals. In this study, a Bayesian approach is taken to estimate GLMMs for clustered skewed dental data. A Gamma GLMM and a log-normal model are employed to allow for heterogeneity across clusters, deriving from the patient-operator-tooth susceptibility typical of this clinical context. A comparison to the frequentist framework is also provided. In our case, Gamma GLMM fits data better than the log-normal distribution, while providing more precise estimates compared with the likelihood approach. A key advantage of the Bayesian framework is its ability to readily provide a flexible approach for implementation while simultaneously providing a formal procedure for solving inference problems.

Journal of Biomedical Informatics, Jan 1, 2008

Web-based surveillance systems enhance the ability for identifying, estimating and assessing publ... more Web-based surveillance systems enhance the ability for identifying, estimating and assessing public health hazards.In this paper we describe the development of a Web-based surveillance registry called Susy Safe for inorganic foreign body injuries in children aged 0–14. The Susy Safe system, which collected 2103 cases during 2000–2002 in 19 European countries, allows for notifying from physicians over the internet thus taking advantage of Web reporting capabilities. Functions include automated risk analysis engine and results visualization. Risk analysis engine has been implemented in a Bayesian framework and provides an update estimate of the risk profile of the products causing injuries, effectively as new data become available.The system contributes to simplify the physician reporting and improve public health information dissemination within consumers and consumers’ association. Also it gives physician and researcher the access of a large amount of data otherwise scattered all around in different hospitals. Finally, supplying a quantitative risk assessment for the identification of hazardous characteristics of objects, such as dimensions or shape, it works toward an improvement of consumer products’ safety design.

The aim of the present study is to understand how different definitions of snacking influence the... more The aim of the present study is to understand how different definitions of snacking influence the estimated probability of obesity in the presence of concurrent risk factors. Factors influencing obesity were evaluated by reviewing the relevant literature through a PUBMED search. Six different modalities to define snack consumption were identified. A Bayesian network model in which nodes represent the variables that the retrieved studies indicate as affecting the probability of obesity was implemented and used to estimate the individual risk of developing obesity taking into account the concurrent effect of the considered risk factors. For a subject with a given profile of factors, the probability of obesity varies according to the chosen definition of snacking, up to maximum of 70%. The variability of the probability of obesity attributable to the chosen definition of snacking is very high and may threaten any conclusion about the effect of snacking, which may be related to the specific definitions adopted in the study.

Journal of medical …, Jan 1, 2011

The American journal of …, Jan 1, 2012

Purposes: Bedside lung ultrasound (LUS) is useful in detecting radio-occult pleural-pulmonary les... more Purposes: Bedside lung ultrasound (LUS) is useful in detecting radio-occult pleural-pulmonary lesions. The aim of our study is to compare the value of LUS with other conventional routine diagnostic tools in the emergency department (ED) evaluation of patients with pleuritic pain and silent chest radiography (CXR). Methods: Ninety patients consecutively admitted to the ED with pleuritic pain and normal CXR were retrospectively (n = 49) and prospectively (n = 41) studied. All patients were blindly examined by LUS and submitted to clinical examination and blood samples. The ability of blood tests and symptoms to predict any radio-occult pleural-pulmonary condition confirmed by conclusive image techniques and follow-up was evaluated and compared with LUS. Results: In 57 cases, the final diagnosis was chest wall pain. The other 33 patients were diagnosed with a pleural-pulmonary condition (22 pneumonia, 2 pleuritis, 7 pulmonary embolism, 1 lung cancer, 1 pneumothorax). Lung ultrasound showed a sensitivity of 96.97% (95% confidence interval [CI], 84.68%-99.46%) and a specificity of 96.49% (95% CI, 88.08%-99.03%) in predicting radio-occult pleural-pulmonary lesions and significantly higher area under the curve (AUC) of receiver operating characteristic analysis (AUC, 0.967; 95% CI, 0.929-1.00) than D-dimer (AUC, 0.815; 95% CI, 0.720-0.911) and white blood cell count (AUC, 0.778; 95% CI,. None of the other routine tests considered or a combination between them better predicted the final diagnosis. Conclusions: Chest radiography and blood tests may be inadequate in the diagnostic process of pleuritic pain. In case of silent CXR, LUS is critical for identifying patients with pleural-pulmonary radio-occult conditions at bedside and cannot be safely replaced by other conventional methods.

International journal of …, Jan 1, 2007

Reproductive Biology …, Jan 1, 2009

Background: this study aims to evaluate the effectiveness and safety of laparoscopic conservative... more Background: this study aims to evaluate the effectiveness and safety of laparoscopic conservative management of ureteral endometriosis.

… methods & research, Jan 1, 2009

The scale-up estimator is a network-based estimator for the size of hidden or hard to count subpo... more The scale-up estimator is a network-based estimator for the size of hidden or hard to count subpopulations. Several issues arise in the public health context when the aim is the estimation of injuries occurring in a certain population, where two common problems are present: (a) Small injuries are usually difficult to observe and rarely reported in the official data and (b) people are not always compliant in giving information about some specific injuries, in particular when children are involved. This study checked the methodological issues arising from using a computer-assisted telephone interview (CATI) survey using the scale-up methodology for detecting the number of injuries due to choking in children ages 0 to 14 in Italy. For this purpose, 1,000 CATI interviews were conducted during a week using a questionnaire based on 33 questions about populations of known size according to census data. Then, each respondent was asked about other questions related to the main target population (e.g., number of children Downloaded from known to suffer from a choking accident). A sensitivity analysis was conducted for estimating the effect of varying subpopulations, order of the questions, and interviewer effects on the resulting estimates. For the interviewer effect, no particular differences were observed in the overall estimates of injuries. The conclusion is the scale-up estimator in association with CATI methodology shows a high potential in the field of injury prevention, being accurate and robust, but particular attention should be given to the training of the interviewers to improve stability of the estimates.

Risk …, Jan 1, 2007

The entry of a small item into the upper airways is one of the leading causes of injuries in chil... more The entry of a small item into the upper airways is one of the leading causes of injuries in children up to 14 years old. The aim of this study is to characterize types of objects causing choking along with the features of the children involved in the accident and compare results with current standards. The European Survey on Foreign Bodies Injuries Study (ESFBI) collected data on foreign body injuries from 19 European countries. The data from ESFBI were selected according to the ICD-9-CM codes 933 (foreign body in the pharynx and larynx) and 934 (foreign body in the trachea, bronchi, and lungs). Both a classification tree and a linear discriminant analysis (LDA) have been set up to predict the probability that an injured child experiences a hospitalization. The classification tree provides flowchart-type decision rules and allows for analyzing the impact of the item features, the children characteristics, and the circumstances of the accidents on the severity of the foreign body injuries. Results showed that children younger than 3.5 who are involved in an accident have a high probability to experience a hospitalization.

Journal of Minimally …, Jan 1, 2010

To compare feasibility and surgical outcome of laparoscopic gynecologic surgery between obese, ov... more To compare feasibility and surgical outcome of laparoscopic gynecologic surgery between obese, overweight, normal-weight, and underweight women. Retrospective case control study (Canadian Task Force classification II-3). Surgery Unit of Minimally Invasive Gynaecology. A total of 503 women who underwent laparoscopic procedures for both benign disease and malignancies. Four main categories of gynecologic disease were identified: uterine fibroids, benign adnexal masses, endometriosis, and endometrial cancer (stage I). For each category patients were divided into 4 groups: underweight (BMI &amp;amp;amp;amp;amp;lt;18.5 kg/m(2)), normal-weight (BMI 18.5-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)), and obese (BMI ≥30 kg/m(2)). Selected outcomes were duration of surgery, rate of laparotomy conversion, intraoperative and postoperative complications, and duration of hospital stay. No statistical difference regarding demographic data, surgical and medical history, and intraoperative findings was present between groups. No laparotomy conversion occurred. Regarding duration of surgery, we found no statistical difference among the BMI groups with regard to benign diseases, whereas pelvic lymphadenectomy in obese patients with endometrial cancer had a statistically significant longer duration than in the control group (122 +/- 47 min vs 65 +/- 21 min, p &amp;amp;amp;amp;amp;lt;.001). The postoperative complication rate was 0.01%: 3 cases of blood transfusion and 1 case of hemoperitoneum among myomectomies; 1 ureteral fistula in surgery for pelvic endometriosis; and 1 case of postoperative lymphocele in endometrial cancer group. No statistically significant difference was found in duration of hospital stay among the BMI groups in any of the categories of disease. For each category we conducted an analysis to identify any possible risk factors other than BMI in the surgical outcomes. Laparoscopic approach in the various applications of gynecologic surgery does not appear to be significantly influenced by BMI in terms of surgical outcomes, laparotomy conversion rate, intraoperative and postoperative complications rate, and duration of hospital stay. The technical difficulties can be solved if skilled surgeons and anesthetists are available.

Pediatrics …, Jan 1, 2010

OBJECTIVE: In the young children, particularly those aged from 1 to 3 years, aerodigestive tract ... more OBJECTIVE: In the young children, particularly those aged from 1 to 3 years, aerodigestive tract foreign bodies (FB) are a common pediatric problem. The aim of this work is to characterize the risk of complications and prolonged hospitalization due to foreign bodies (FB) in the upper digestive tract in terms of the characteristics of the injured patients (age, gender), typology and features of the FBs, the circumstances of the accident and the hospitalization's details. METHODS: A retrospective study in 19 Hospitals of corresponding 19 European countries was realized on 2103 children aged 0-14. In 186 cases, it was reported an injury due to the presence of a FB in the mouth, esophagus and stomach (ICD935). RESULTS: Complications arose in 14 cases and hospitalization was required in 164 cases. No deaths were observed. A higher incidence of hospitalization in males (61%) was observed. Median age for children who experienced complications was 2 years old. The most common FB removal technique was esophagoscopy. In the majority of the cases, children were treated by ENT Department. The most common FBs were nuts, seeds, berries, corn and beas: in general, small, round crunchy foods pose a risk of choking. CONCLUSION: Coins, batteries and fish bones among food were the most common type of FB. Since recent development of technology has accelerated broad use of disk-type batteries, parents should be aware of this hazard, and an educational campaign for public education for this serious problem might be advisable.