Early prediction of gestational diabetes mellitus using maternal demographic and clinical risk factors

OBJECTIVE

To build and validate an early risk prediction model for gestational diabetes mellitus (GDM) based on first-trimester electronic medical records including maternal demographic and clinical risk factors.

METHODS

To develop and validate a GDM prediction model, two datasets were used in this retrospective study. One included data of 14,015 pregnant women from Máxima Medical Center (MMC) in the Netherlands. The other was from an open-source database nuMoM2b including data of 10,038 nulliparous pregnant women, collected in the USA. Widely used maternal demographic and clinical risk factors were considered for modeling. A GDM prediction model based on elastic net logistic regression was trained from a subset of the MMC data. Internal validation was performed on the remaining MMC data to evaluate the model performance. For external validation, the prediction model was tested on an external test set from the nuMoM2b dataset.

RESULTS

An area under the receiver-operating-characteristic curve (AUC) of 0.81 was achieved for early prediction of GDM on the MMC test data, comparable to the performance reported in previous studies. While the performance markedly decreased to an AUC of 0.69 when testing the MMC-based model on the external nuMoM2b test data, close to the performance trained and tested on the nuMoM2b dataset only (AUC = 0.70).

Feature selection for unbiased imputation of missing values: A case study in healthcare

Datasets in healthcare are plagued with incomplete information. Imputation is a common method to deal with missing data where the basic idea is to substitute some reasonable guess for each missing value and then continue with the analysis as if there were no missing data. However unbiased predictions based on imputed datasets can only be guaranteed when the missing mechanism is completely independent of the observed or missing data. Often, this promise is broken in healthcare dataset acquisition due to unintentional errors or response bias of the interviewees. We highlight this issue by studying extensively on an annual health survey dataset on infant mortality prediction and provide a systematic testing for such assumption. We identify such biased features using an empirical approach and show the impact of wrongful inclusion of these features on the predictive performance.Clinical relevance- We show that blind analysis along with plug and play imputation of healthcare data is a potential pitfall that clinicians and researchers want to avoid in finding important markers of disease.

The influence of humidity on the viscoelastic behaviour of human hair

The possibility of curling hair is attributed to the fact that the mechanical properties of hair fibres depend on time, temperature and humidity. In this study the dependence of the viscoelastic behaviour of human hair fibres on humidity is characterised in a bending deformation. An experimental set-up was used to perform bending relaxation measurements at different humidities. The relaxation data were fitted using a so-called "stretched exponential equation". The humidity dependence was incorporated by applying time-humidity superposition. Also, the influence of humidity on the initial E-modulus was found. The influence of humidity on the behaviour of human hair fibres could be modelled by using a general characterisation of the behaviour of human hair fibres. The general characterisation is used to predict the recovery in a human hair fibre after curling. The predicted recovery appeared to agree reasonably well with experimentally determined values.

Childhood lymphoma in southern Iran

A study of 81 childhood lymphomas diagnosed in the Department of Pathology of Pahlavi University Medical Center, Shiraz, Iran, encompassing all histologically diagnosed childhood lymphomas from the Fars Province, Southern Iran over a 14-year period (1963--1976) revealed a 3:1 male predominance and a 1:4 frequency compared to adult lymphomas. Peripheral lymphadenopathy at the initial physical examination was almost twice as common as deep node involvement. Comparison of cumulative and age-standardized (to world population) incidence rates with those of selected Tumor Registries in various continents revealed a higher rate in our region of both non-Hodgkin's and Hodgkin's lymphoma relative to some of the Western countries. Our incidence rates were in general intermediate between Western populations on one hand and some South America, African and Asian populations on the other. Hodgkin's disease accounted for 64% (males) and 88% (females) of lymphomas and mixed cellularity was the commonest histologic subtype. Histologically almost all non-Hodgkin's lymphomas were diffuse at the time of diagnosis.

Asymptomatic gonococcal urethritis in a male transsexual female

Images

Acute lung injury induced by cadmium aerosol. II. Free airway cell response during injury and repair

This paper presents a study of the effects of cadmium chloride aerosol on free airway cell populations. Rats were given a single exposure to aerosolized 0.005 M CdCl2 dissolved in physiologic saline. CdCl2 exposure induced a fivefold increase to 43.2 X 10(6) total cells at 4 days as compared with 11.1 X 10(6) in saline-exposed controls and 8.4 X 10(6) in unexposed rats (P less than 0.001). Differential counts showed a peak of polymorphonuclear leukocytes (PMN) at 3 days after CdCl2 exposure, whereas values for saline-exposed animals showed no change from values for unexposed animals (P less than 0.001). Four days after CdCl2 exposure thepredominant cell was the alveolar macrophage (AM), which showed a highly significant increase in number and size over saline-exposed and unexposed animals. A significant increase in lymphocytes also occurred, with a peak at 4 days. At 10 days after exposure, AM were still more numerous after CdCl2 exposure (P less than 0.001), but all other cell types had returned to control levels. Correlation with previous ultrastructural studies on CdCl2 exposure suggested the peak of PMN coincided with Type I cell necrosis. In contrast, AM predominated durion and phagocytosis occur.