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M Martuzzi

Publications and source records attributed to M Martuzzi.

At least 37 records · Page 2Linked to original sources
PubMed1980

[Nosology of contraceptives: hematological and ultrastructural observations after experimental administration of low dosage contraceptives (author's transl)].

A further experimental study on changes produced in rabbits by low dosage contraceptives is presented. The administration has been continued for six months. Serum biochemical and hepatic ultrastructural findings are in agreements with literature data. On the contrary the early changes of cardiac microcirculation and chiefly renal glomerular tuft seem to be rather unusual. The weight to be attached to the knowledges descending from the presented data in assessing allowance of contraceptive treatments in human subjects and aiming preventive medicine purposes is emphasized.

Animals↗
PubMedDate not supplied

Empirical Bayes estimation of small area prevalence of non-rare conditions.

Geographical studies are becoming increasingly common in epidemiology. The problems of small area investigations are well known, and several methods are available for the estimation and mapping of disease risk across small areas, with the emphasis mainly on applications concerning rare disease incidence or mortality. An empirical Bayes method is proposed for small area estimation of the prevalence of non-rare conditions, whose variability is binomial and cannot be approximated by a Poisson model. It is the direct equivalent of a semi-parametric non-iterative moment estimation method proposed in the Poisson case. As an example, the geographical distribution of the prevalence of respiratory symptoms in schoolchildren across 71 small areas in Huddersfield, Northern England is studied. Whereas random variability causes the crude area-specific prevalences to be unstable, the posterior estimates, corrected towards overall or local means, are capable of highlighting genuine extra-binomial variability. The method is very simple and can readily be applied to the study of a number of common conditions.

Air Pollution↗
PubMedDate not supplied

Non-parametric maximum likelihood estimators for disease mapping.

A Non-Parametric Maximum Likelihood approach to the estimation of relative risks in the context of disease mapping is discussed and a NPML approximation to conditional autoregressive models is proposed. NPML estimates have been compared to other proposed solutions (Maximum Likelihood via Monte Carlo Scoring, Hierarchical Bayesian models) using real examples. Overall, the NPML autoregressive estimates (with weighted term) were closer to the Bayesian estimates. The exchangeable NPML model ranked immediately after, even if it implied a greater shrinkage, while the truncated auto-Poisson showed inadequate for disease mapping. The coefficients of the autoregressive term for the different mixtures have clear interpretations: in the breast cancer example, the larger cities in the region showed high rates and very low correlation with the neighbouring areas, while the less populated rural areas with low rates were strongly positively correlated each other. This pattern is expected since breast cancer is strongly correlated with parity and age at first birth, and the female population of the rural areas experienced a decline in fertility much later than those living in the larger cities. The leukemia example highlighted the failure of the Poisson-Gamma model and other general overdispersion tests to detect high risk areas under specific conditions. The NPML approach in Aitkin is very general, simple and flexible. However the user should be warned against the possibility of local maxima and the difficulty in detecting the optimal number of components. Special software (such as CAMAN or DismapWin) had been developed and should be recommended mainly to not experienced users.

Algorithms↗
PubMedDate not supplied

Declining trends of male proportion at birth in Europe.

Declining trends in male proportion at birth observed in several Western countries might reflect widespread exposure to pollutants capable of interfering with human reproduction. In this study, the authors describe male live birth proportion trends in 23 European countries from 1950 to 1996 (total of 305 million live births). Overall, there was a significant linearly decreasing trend of 10 fewer males per 100,000 births each year, resulting in a loss of 73,462 boys during a 47-yr period. The proportion of male births during the first 3 yr of the study period was higher than in the last 3 yr in 18 countries (i.e., 78%). Decreasing trends, which varied in slope and shape, were observed in 11 countries; no significant trend was found in 8 countries, and male birth proportion increased in 4 countries. The results of this study confirmed that the proportion of male births is declining in Europe, and differences exist by region and country. Social and cultural aggregations of countries with decreasing trends suggest that sociodemographic characteristics might be more likely to explain trends than environmental exposures to chemicals. Investigators should evaluate this hypothesis to assess the usefulness of male birth proportion as a sentinel event.

Birth Certificates↗
PubMedDate not supplied

[Deprivation and mortality: a deprivation index suitable for geographical analysis of inequalities].

UNLABELLED: FOREGROUND: A national deprivation index suitable for geographical analysis of inequalities in health is not yet available in Italy, although the link between deprivation and health has been clearly demonstrated in our country in a number of studies. OBJECTIVES: 1) To describe a deprivation index in Italy at municipal level, based on the percentage of selected census variables (simple components) 2) To analyse general mortality according to deprivation categories at municipal level in Italy 3) To measure the size of ecological bias using the Turin Longitudinal Study. SETTING: Italy (1-2), Turin (3). MATERIALS: 1) 1991 census data base at municipal level 2) General mortality in Italy by municipality and age bands in 1990-92. 3) Turin Longitudinal study 1991-1995. METHODS: 1) Percentages of selected indicators of inequalities for all the 8.100 Italian municipalities present at 1991 census were calculated. Factorial analysis were performed in order to help in selecting the most valuable ones. The final choice led to five indicators (low education, unemployment, rented occupier housing, no indoor bathroom, lone parent with childhood). A simple additive index was computed using the method of the sum of normal standard deviates of each component 2) Correlation of indexes with mortality was performed; SMR for each deprivation category were computed; 3) Computation of the index at different levels: individual (one million individuals), census ward (3657 wards), statistic zone (92 statistic zones), two neighborough levels (23 and 10 neighboroughs) was conducted; differential analysis was performed for each level and index category, allowing for comparison among results, adjusting for age. MAIN RESULTS: Increasing deprivation was significantly associated with mortality from all causes: there was up to a 20 percent increase in mortality between the highest and lowest quintile. The relationship was linear with no apparent threshold. The slope of the relationship between deprivation and mortality varied among regions. Differentials in inequalities measured by individual and census tract level resulted to be very small; ecological bias arises when larger areas are taken into account. CONCLUSIONS: An area based measure of deprivation has proved a valuable tool in examining differentials in death and is likely to prove of continuing value to health authorities in planning the delivery of health care.

Adolescent↗