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The problem of discrimination and classification is central to much of epidemiology. Here we consider the estimation of a logistic regression/discrimination function from training samples, when one of the training samples is subject to misclassification or mislabeling, e.g. diseased individuals are incorrectly classified/labeled as healthy controls. We show that this leads to zero-inflated binomial model with a defective logistic regression or discrimination function, whose parameters can be estimated using standard statistical methods such as maximum likelihood. These parameters can be used to estimate the probability of true group membership among those, possibly erroneously, classified as controls. Two examples are analyzed and discussed. A simulation study explores properties of the maximum likelihood parameter estimates and the estimates of the number of mislabeled observations. [ABSTRACT FROM AUTHOR]

Several statistical methods have been developed for adjusting the Odds Ratio of the relation between two dichotomous variables X and Y for some confounders Z. With the exception of the Mantel-Haenszel method, commonly used methods, notably binary logistic regression, are not symmetrical in X and Y. The classical Mantel-Haenszel method however only works for confounders with a limited number of discrete strata, which limits its utility, and appears to have no basis in statistical models. Here we revisit the Mantel-Haenszel method and propose an extension to continuous and vector valued Z. The idea is to replace the observed cell entries in strata of the Mantel-Haenszel procedure by subject specific classification probabilities for the four possible values of (X,Y) predicted by a suitable statistical model. For situations where X and Y can be treated symmetrically we propose and explore the multinomial logistic model. Under the homogeneity hypothesis, which states that the odds ratio does not depend on Z, the logarithm of the odds ratio estimator can be expressed as a simple linear combination of three parameters of this model. Methods for testing the homogeneity hypothesis are proposed. The relationship between this method and binary logistic regression is explored. A numerical example using survey data is presented. [ABSTRACT FROM AUTHOR]

Aim Long-chain polyunsaturated fatty acid (LCPUFA) supplementation of infant formula may have a beneficial effect on cognitive development. This study aimed to investigate the effect of LCPUFA formula supplementation primarily on cognition and secondarily on behaviour at age 9 years. Special attention was paid to the potentially modifying effect of maternal smoking during pregnancy. Method A double-blind, randomized control study was performed in two groups of healthy infants born at term: one group, constituting the control group, received standard formula ( n=169) and another group received standard formula supplemented with LCPUFAs ( n=146). A breastfed group ( n=159) served as an additional reference. At 9 years of age, 72% of the children (control group: n=123; 71 males, 52 females; LCPUFA group: n=91; 42 males, 49 females; breastfed group: n=127, 64 males, 63 females) underwent extensive cognitive and behavioural testing. Results An interaction between infant nutrition and smoking during pregnancy was found. Among children exposed to smoking during pregnancy, LCPUFA supplementation was associated with higher mean verbal IQ scores ( p=0.007) and learning and memory ( p=0.006). Among children not exposed to smoking during pregnancy, LCPUFA supplementation was associated with lower mean verbal memory scores ( p=0.003). Executive function scores were significantly lower in the LCPUFA-supplemented group than in the control group ( p=0.001). Breastfeeding was associated with better performance on IQ ( p=0.005). Interpretation No consistent beneficial effect of LCPUFA formula supplementation on cognitive development in term-born infants was found. The study confirmed that breastfeeding is associated with better cognition. [ABSTRACT FROM AUTHOR]

Background: Acute generalized exanthematous pustulosis (AGEP) represents a severe, acute, pustular skin reaction that is most often induced by drugs. AGEP can be difficult to differentiate from generalized pustular psoriasis (GPP) both clinically and histopathologically. We present a systematic description of the histopathological spectrum of AGEP and GPP with a focus on discriminating features. Materials and methods: A retrospective, descriptive, comparative histopathological study was completed utilizing step sections of 43 biopsies of 29 cases with a validated diagnosis of probable or definite AGEP and 24 biopsies of 19 cases with an established diagnosis of GPP. Results: In AGEP, biopsies from erythema and pustules showed minor differences, whereas histopathology of the acute stage of GPP showed major differences compared to the chronic stage. Comparing AGEP and GPP, the presence of eosinophils, necrotic keratinocytes, a mixed interstitial and mid-dermal perivascular infiltrate and absence of tortuous or dilated blood vessels were in favor of AGEP. Moreover, chronic GPP was characterized by prominent epidermal psoriatic changes. The frequency of a psoriatic background of AGEP patients in our study was higher than that of psoriasis in the general population. However, histopathology of a subgroup of AGEP patients with a personal history of psoriasis revealed no significant differences from the other AGEP patients. Conclusions: The spectrum of histopathological features of both AGEP and GPP is presented. Despite considerable overlap, subtle consistent histopathological differences and the grade of severity of specific features can help in differentiation. We could neither substantiate earlier reports that follicular pustules exclude AGEP nor did we see vasculitis as a specific feature in AGEP. Our study also supports the concept that AGEP is a separate entity that is distinct from GPP. Kardaun SH, Kuiper H, Fidler V, Jonkman MF. The histopathological spectrum of acute generalized exanthematous pustulosis (AGEP) and its differentiation from generalized pustular psoriasis. [ABSTRACT FROM AUTHOR]

Aim The Infant Motor Profile (IMP) is a qualitative assessment of motor behaviour of infants aged 3 to 18 months. The aim of this study was to investigate construct validity of the IMP through the relation of IMP scores with prenatal, perinatal, and neonatal variables, including the presence of brain pathology indicated by neonatal ultrasound imaging of the brain. Method A longitudinal prospective study was performed in a group of 30 term infants (12 females, 18 males; median gestational age 40.1wks, range 37.6–42wks) and 59 preterm infants (25 females, 34 males; median gestational age 29.7wks, range 25–34.7wks). IMP assessments were performed at (corrected) ages of 4, 6, 10, 12, and 18 months. Socio-economic and perinatal data were collected, which, in the case of preterm infants, included information on periventricular leukomalacia and intraventricular haemorrhage based on neonatal cranial ultrasound. Data were analysed by fitting mixed-effects models. Results Gestational age, socio-economic status, and 5-minute Apgar scores were significant determinants of IMP scores in the total group of infants ( p<0.001, <0.002, and <0.042 respectively). In the subgroup of preterm infants, IMP scores were significantly affected by brain lesions on neonatal ultrasound ( p<0.001) and by socio-economic status ( p=0.001). Interpretation The findings support the construct validity of the IMP: IMP scores are clearly associated with relevant determinants of neuromotor function. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between blood group and waiting time until transplantation or death on the waiting list. All patients listed for liver transplantation in the Netherlands between 15 December 2006 and 31 December 2012, were included. Study variables were gender, age, year of listing, diagnosis, previous transplantations, blood group, urgency, and MELD score. Using a competing risks analysis, separate cumulative incidence curves were constructed for death on the waiting list and transplantation and used to evaluate outcomes.In 517 listings, the mean death rate per 100 patient-years was 10.4. A total of 375 (72.5% of all listings) were transplanted. Of all transplantations, 352 (93.9%) were ABO-identical and 23 (6.1%) ABO-compatible. The 5-year cumulative incidence of death was 11.2% ( SE 1.4%), and of transplantation 72.5% ( SE 2.0%). Patient blood group had no multivariate significant impact on the hazard of dying on the waiting list nor on transplantation. Age, MELD score, and urgency status were significantly related to the death on the waiting list and transplantation. More recent listing had higher probability of being transplanted. In the MELD era, patient blood group status does not have a significant impact on liver transplant waiting list mortality nor on waiting time for transplantation. [ABSTRACT FROM AUTHOR]

The article presents a study concerning the significance of faecalprotectin in the diagnosis of inflammatory bowel diseases. It states that faecalprotectin test reduces the number of endoscopic procedures in children and adults. It mentions that the test is effective in the diagnosis of inflammatory bowel diseases but the results are delayed in eight percent of the affected patients.

Objective: To evaluate the effect of preimplantation genetic screening (PGS) on neurodevelopmental outcomes in children. Design: Prospective, assessor-blinded, follow-up study of children born to women randomly assigned to in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) with or without PGS. Setting: University Medical Center, Groningen, and Academic Medical Center, Amsterdam, the Netherlands. Patient(s): Fifty-four PGS children and 77 controls. Intervention(s): PGS. Main Outcome Measure(s): Mental, psychomotor, neurologic, and behavioral outcomes in 2-year-old children as measured with the Bayley Scales of Infant Development, the Hempel neurologic examination, and the Child Behavior Check List. Result(s): The mental, psychomotor, and behavioral outcomes at 2 years in children born after IVF with and without PGS were similar overall. The PGS children showed lower neurologic optimality scores than the control children. Scores on all tests were within the normal range. Conclusion(s): Conception with PGS does not seem to be associated with impaired mental, psychomotor, or behavioral outcomes by age 2. However, the lower neurologic optimality scores found in the PGS children may signal less favorable long-term neurologic outcomes in PGS children. Our findings stress the need for safety evaluations with new assisted reproductive techniques before large-scale implementation. [ABSTRACT FROM AUTHOR]

It has been shown that transcutaneous electrical neurostimulation (TENS) reduces sympathetic tone. Spinal cord stimulation (SCS) has proven qualities to improve coronary, peripheral, and cerebral blood circulation. Therefore, we postulate that TENS and SCS affect the autonomic nervous system in analogous ways. In this line of thought, cervical application of TENS might be a useful and simple adjunct in the treatment of cerebrovascular disease by improving cerebral blood flow. Experiments were performed in order to assess whether cervical TENS is safe and whether an effect on cerebral blood flow velocity (CBFV) can be shown in healthy subjects. A controlled, non-randomized, phase 1 study was performed with 20 healthy volunteers. Cervical TENS was applied in several frequencies, with and without hyperventilation. Continuous registration of blood pressure, pulse, CBFV (estimated by transcranial Doppler sonography) and end-tidal carbon dioxide concentration was performed. Cervical TENS was well-tolerated by all subjects. Despite small effects on heart rate (HR) and mean arterial blood pressure (MAP), a significant effect on middle cerebral artery (MCA) blood flow velocity was not demonstrated. No effect of age, gender, current or session order on MCA, HR, or MAP was found. TENS did not influence the effect of hyperventilation. In these experiments, application of cervical TENS is proven to be a safe procedure. However, no effects on cerebral blood flow velocity could be detected, perhaps due to the intact cerebral autoregulation in the healthy volunteers. [ABSTRACT FROM AUTHOR]

The article examines whether women who had preeclampsia demonstrate increased intima-media thickness (IMT), as a marker of early atherosclerosis, compared with women with normal pregnancies or nulliparous women. Results reveal that preeclampsia and, to a lesser extent, normal pregnancy, are related to increased IMT. The link between increased IMT and preeclamptic pregnancy leads to the question of which comes first.

Summary: Background: Apoptosis related proteins in early staged NSCLC seem to have prognostic value. We studied the value of a combination of eight of those proteins in advanced NSCLC. Patients and methods: Bronchoscopically procured tumor biopsies of NSCLC patients were stained immunohistochemically and rated for expression of eight different cellular proteins. Patients were treated with 60Gy radiotherapy with or without carboplatin as radiosensitizer. Results: Apoptotic proteins in tumors that showed positive staining were the highest for Bax (99%), Fas (92%), FasL (87%), Rb (87%), p21(WAF1) (73%), and p53 (70%), and the lowest for c-myc (58%) and Bcl-2 (58%). In the Cox regression analysis Bcl-2 positivity (RR=0.61, 95% CI, 0.37–0.98, p =0.04) was predictive for overall survival. Only Bcl-2 staining percentage (RR10 (RR associated with an increase in stained cells of 10%)=0.93, 95% CI, 0.89–0.99), p53 (RR10 =0.94, 95% CI, 0.89–0.99) and FasL (RR10 =0.92, 95% CI, 0.86–0.99) were predictive for a longer progression-free survival. No specific constellation of apoptotic proteins was associated with tumor response. Conclusion: Bcl-2 expression in tumor tissue of patients with unresectable NSCLC predicts a better overall survival, while Bcl-2, p53, and FasL expressions predict for a longer progression-free survival. [Copyright &y& Elsevier]

The standard therapy for patients with fever and chemotherapy-related neutropenia is hospitalization and infusion of broad-spectrum antibiotics. Early discharge of a defined group of patients at low risk for septicaemia would be of great advantage for these patients. In this study plasma interleukin-8 (IL-8) and interleukin-6 (IL-6) levels measured at start of fever (n = 72) could define a low-risk group of febrile patients with neutropenia due to chemotherapy. For this purpose we collected and analysed data on 72 fever episodes from 53 patients with chemotherapy-related neutropenia, aged between 1 and 66 years. Of the 72 episodes, 18 were classified as bacteraemia and/or clinical sepsis (sepsis group). The IL-6 and IL-8 plasma concentration were significantly increased in patients with chemotherapy-related neutropenia and fever due to bacteraemia versus fever of non-bacterial origin (P = 0.043 and P = 0.022 respectively). Logistic regression analysis, with sepsis as the outcome variable, revealed significant effects of age combined with either IL-6 or IL-8. Sepsis occurrence was lowest for patients <16 years and highest in patients between 16 and 50 years, and was higher in patients with increased IL-6 (P = 0.032) or IL-8 (P = 0.049). No significant effect of leucocyte count, C-reactive protein, sex or underlying malignancy at presentation was detected. The plasma IL-6 and IL-8 levels were fairly strongly correlated (Pearson r = 0.62). Using a cut-off value with 100% sensitivity, both IL-8 and IL-6 could define a low-risk group of neutropenic patients of 28% (CI 15–40%) at the start of the febrile period. Intervention studies are warranted to confirm this result and to investigate whether an early discharge based on IL-8 or IL-6 measurement is safe, increases the quality of life, and results in cost savings. [ABSTRACT FROM AUTHOR]

Background: Determining the stage of non–small-cell lung cancer often requires multiple preoperative tests and invasive procedures. Whole-body positron-emission tomography (PET) may simplify and improve the evaluation of patients with this tumor. Methods: We prospectively compared the ability of a standard approach to staging (computed tomography [CT], ultrasonography, bone scanning, and, when indicated, needle biopsies) and one involving PET to detect metastases in mediastinal lymph nodes and at distant sites in 102 patients with resectable non–small-cell lung cancer. The presence of mediastinal metastatic disease was confirmed histopathologically. Distant metastases that were detected by PET were further evaluated by standard imaging tests and biopsies. Patients were followed postoperatively for six months by standard methods to detect occult metastases. Logistic-regression analysis was used to evaluate the ability of PET and CT to identify malignant mediastinal lymph nodes. Results: The sensitivity and specificity of PET for the detection of mediastinal metastases were 91 percent (95 percent confidence interval, 81 to 100 percent) and 86 percent (95 percent confidence interval, 78 to 94 percent), respectively. The corresponding values for CT were 75 percent (95 percent confidence interval, 60 to 90 percent) and 66 percent (95 percent confidence interval, 55 to 77 percent). When the results of PET and CT were adjusted for each other, only PET results were positively correlated with the histopathological findings in mediastinal lymph nodes (P<0.001). PET identified distant metastases that had not been found by standard methods in 11 of 102 patients. The sensitivity and specificity of PET for the detection of both mediastinal and distant metastatic disease were 95 percent (95 percent confidence interval, 88 to 100 percent) and 83 percent (95 percent confidence interval, 74 to 92 percent), respectively. The use of PET for clinical staging resulted in a different stage from the one determined by standard methods in 62 patients: the stage was lowered in 20 and raised in 42. Conclusions: PET improves the rate of detection of local and distant metastases in patients with non–small-cell lung cancer. (N Engl J Med 2000;343:254-61.) [ABSTRACT FROM AUTHOR]