Development of a Food-Based Diet Quality Scale for Brazilian Schoolchildren Using Item Response Theory.

Item response theory (IRT) is a psychometric method that provides probabilistic model-based measurements. Its use is relatively recent in the assessment of food consumption, especially through dietary assessment tools. This study aims (1) to develop a food-based diet quality scale for Brazilian schoolchildren using IRT, and (2) to apply the scale to a representative sample of schoolchildren from a Southern Brazilian city. The scale was developed with daily consumption frequency of foods from 835 students who completed the Food Intake and Physical Activity of Schoolchildren questionnaire. Questionnaire foods were grouped into 10 items according to their nutritional similarities and were evaluated by full-information factor analysis that indicated a dominant factor explaining 28% of the variance. Psychometric item analysis was performed using Samejima's model. The scale covered all levels of diet quality, from "very poor" (scores < 95) to "very good" (scores ≥ 130). Children who had higher diet quality scores consumed beans, meat, fish, eggs, fruits, vegetables, dairy products, and water more frequently, while reducing the consumption of ultraprocessed sugary foods, ultraprocessed savoury snacks and sausages, and sugary drinks. Of 6323 children, an average of less than 10% consumed the highest diet quality scores (good or very good diet quality) and about 60% of children consumed low diet quality scores. The scale can be applied to other schoolchildren with the same measure precision.

A model for psychiatric questionnaires with embarrassing items.

We propose an item response theory model to analyse psychiatric questionnaires that contain embarrassing items. We use Bayesian methods to estimate its parameters and consider a simulation study to evaluate the performance of the proposed estimators. The results are illustrated with the analysis of data collected to evaluate teenager depression, highlighting the gender difference in the probabilities of 'crying crisis', a trait known to embarrass some male populations.

Comparision of the BAX® System with an in-house MSRV method for the detection of Salmonella in chicken carcasses and pork meat

A study was performed to compare the analytical procedure of the BAX® System for Salmonella PCR assay with the Modified Semi-Solid Rappaport-Vassiliadis (MSRV) method, for the detection of Salmonella in naturally contaminated chicken carcass samples (n = 762) and raw pork meat (n = 566). The chicken carcasses samples were collected during slaughtering after defeathering or immediately after evisceration and the raw pork meat collected from the deboned head of recently slaughtered pigs and others deboned raw fresh pork meat. The BAX® System detected 134 Salmonella-positive samples in chicken carcasses and 145 samples in pork meat, while the MSRV method isolated 142 and 144 Salmonella-positive samples, respectively. No significant difference was observed between the two methods for chicken carcasses and pork meat, according to McNemar test at the 5 percent level.

Um estudo foi realizado com o objetivo de comparar o procedimento analítico de detecção de Salmonella com o Sistema BAX® automatizado, baseado na Reação em Cadeia da Polimerase (PCR) com o método de Rappaport-Vassiliadis em Agar Semi-Sólido modificado (MSRV) para detecção de Salmonella em amostras de carcaças de frango naturalmente contaminadas (n=762) e retalhos de carne suía (n=566). O Sistema BAX® detectou 134 amostras positivas para Salmonella em carcaças de frango e 145 amostras positivas para Salmonella em retalhos de carne suína, enquanto o MSRV detectou 142 e 144 amostras positivas respectivamente. Não houve diferença estatisticamente significativa entre os dois métodos, segundo McNemar ao nível de significância de 5 por cento.

In utero malnutrition influences wound healing of newborn rats as measured by tensile strength and collagen deposition.

BACKGROUND: Studies have investigated the consequences of intrauterine malnutrition on birth weight and overall survival but not on wound healing. This study aims to assess the influence of in utero malnutrition on wound healing of newborn rats. METHODS: Pregnant Wistar rats were divided into 2 groups. Study rats were given 50% of the food intake of controls throughout pregnancy in a pair-fed manner. The body weight and length of the newborns were measured. Newborns were breast-fed until day 21, when a laparotomy was performed. The effect of the laparotomy was assessed by measure of the wound strength and collagen deposition at postoperative day (POD) 7 (n = 15) and POD 21 (n = 15). RESULTS: The body weight and length of newborns of malnourished mothers were significantly smaller at birth compared with controls (respectively, 4.5 +/- 0.1 g vs 5.8 +/- 0.1 g, p = .0003 and 4.6 +/- 0.1 cm vs 5.2 +/- 0.1 cm, p = .0003). Maximum, rupture, and tensile strength of malnourished newborns were smaller than controls on POD 7 (0.281 +/- 0.031 vs 0.470 +/- 0.031, p = .0061, 0.112 +/- 0.06 kgf vs 0.173 +/- 0.08 kgf, p = .0495 and 0.019 +/- 0.002 kgf/mm2 vs 0.024 +/- 0.003 kgf/mm2, p = .050, respectively). On POD 21, only tensile strength remained lower (0.044 +/- 0.003 kgf/mm2 vs 0.058 +/- 0.003 kgf/mm2, p = .0477). Type I collagen deposition of malnourished newborns was similar to controls on POD 7 (57.69 +/- 10.06 vs 48.34 +/- 15.65, p = .3187) and on POD 21 (75.6 +/- 7.21 vs 80.0 +/- 9.92, p = .4212). CONCLUSIONS: In utero malnutrition decreases the abdominal wound strength of newborn rats but not the collagen deposition, suggesting that breast-feeding nutrition is effective in recovering the collagen deposition but not overall wound strength.