Heritability and genetic correlation: statistical power, population comparisons, and sample size.
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Constitution typology is thought of as a classification that is based on a few fundamental properties of the organism. These properties steadily distinguish individuals and permit the prediction of manifold secondary (external) features of types. At the transition from one constitutional type to another, concordant changes of trait values are determined by the respective changes of general causal factors. Theoretically, external constitution typology should be constructed on the basis of trait concordant "dynamics" under the change of fundamental factors at the individual level. Therefore, it does not depend on statistical relations characterizing population level. Causal factors and their influences on traits are impossible to be correctly and uniquely determined on the basis of population statistics relations. Causal factors do not coincide with the statistical ones of multivariate biometric analysis; equally, trait regression dependencies on statistical factors do not coincide with the causal influences.
The author analyzes the accuracy of the population data published by Sir Thomas Raffles concerning early nineteenth-century Java, Indonesia. Specific topics considered include "a. errors in computation, b. distribution of household size by sub-district, c. distribution of sex-ratio by sub-district, d. variation of age-structure by sub-district, [and] e. problems of Chinese population. Special attention was given to the consistency of the definition of categories and the distribution patterns of the reported figures." (SUMMARY IN ENG)
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This article is an update of a similar article published in Population Trends 104 and complements the article on European-wide issues in population statistics, published in Population Trends 118. The main areas of demography are covered, namely population change, population composition, fertility and mortality. Eurostat are currently working on a new set of population projections which should be available shortly, but were not completed when this article was drafted.
The adolescent years, being a period of unique developmental changes, are of great interest in understanding suicidal behavior. The occurrence of completed suicide by age in 1-year age groups in adolescence and young adulthood was studied via official Finnish mortality statistics and the population statistics. Suicide rates increased sharply by age during adolescence, starting somewhat earlier among boys than among girls. During the periods of rapidly rising and high suicide rates in the 1970s and 1980s among boys, the increase in suicide rates started at a younger age than during a spell of lower rates in the 1960s.
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OBJECTIVE: The purpose of this study was to use population-based information to describe the demographic and tumor characteristics of inflammatory breast cancer (IBC) - the most aggressive form of this disease. METHODS: IBC cases diagnosed during 1994 through 1998 were reported to 26 population-based cancer registries covering approximately 40% of the US population. Rates were expressed per 100,000 female population and age-adjusted to the 2000 US population. Ninety-five percent gamma confidence limits were estimated for the rates. RESULTS: Among the 3626 women diagnosed with IBC during 1994-1998, the majority were 40-59 years old. Most tumors were diagnosed at a regional (68.9%) or distant (25.3%) stage and were poorly differentiated (49.4%). The rate of IBC was 1.3 per 100,000 for all races combined. Black women had the highest risk (1.6) and Asian and Pacific Islander women the lowest (0.7). CONCLUSIONS: IBC is an extremely rare form of breast cancer. More precise diagnostic criteria are needed to distinguish it from less aggressive forms of the disease. Future studies should use a population-based design and collect detailed clinical information, including the presence of erythema, edema or peau d'orange appearance of the skin, and other clinical signs of disease.
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Many biologically important substances are discovered through screening of relevant chemical or biological libraries. The ability to find the active substances ("hits") from any random collection is largely determined by the quality of the assay and screening conditions. When a large population is screened for a specific characteristic, each member of that population is usually tested only once. Errors in the measurements require additional follow-up tests to confirm that each hit from the primary screen is truly active. In this report, we present a statistical model system that predicts the reliability of hits from a primary test as affected by the error in the assay and the choice of the hit threshold (hit limit). The hit confirmation rate, as well as false positive (representing substances that initially fall above the hit limit but whose true activity are below the hit limit) and false negative (representing substances that initially fall below the hit limit but whose true activity are in fact greater than the hit limit) rates have been analyzed with this model by computational simulation. This model can also be used in screen validation and post-screening data analysis. The statistical analysis presented here has broad implications and is applicable to screening of any large population for any specific characteristic. Obvious applications include drug discovery, gene chip analysis, population biology, directed molecular evolution, biological panning, and combinatorial material sciences.
This study compares the actual first year's workload of a new radiation oncology department with that predicted, and assesses the impact of the differences, and their implications for future similar developments. The treatment records and diaries for the Geelong Hospital Radiation Oncology Department were reviewed after the first 12 months of operation (opened in June 1992). Statistics relating to the number of patients seen, number treated, diagnosis, etc., were evaluated and compared to the original estimates based upon population statistics and likely referral rates. Nine hundred and seven new patients were seen in this period, and from them 718 courses of treatment were initiated. One hundred and eighty-nine cases (20% of referrals) were seen but not treated. A further 102 treatment courses (14% of total) were initiated upon patients who had previously been irradiated. Forty-six per cent of patients were managed by 10 fractions or fewer, and a further 23% by 25 or more fractions. Eighty per cent of patients were managed by one or two fields. Electrons were used in only 14% of cases. Further calculations suggested a further possible 441 cases of referral could be expected, based upon current population statistics. Referral rates for radiation oncology are highly dependent on a number of factors. As a result, estimates of referrals and hence the size of a department required for a given population vary widely. Our data support these concepts, and the concept that referral is also strongly dependent upon the distance patients need to travel. In considering the development of units outside of major cities it is suggested that referrals are likely to be on the high side of estimates and a minimum two-machine unit is essential to cover the given workload.
As follows from the population statistical investigation performed within the management information system, defects of the anatomic structure of the feet occur in the pig population of all breeds and cross combinations kept in the Czech Socialist Republic: the frequency of this occurrence is relatively higher than 4.4% (1984) and 3.8% (1985) of all litters affected by some of the genetic defects. In some populations different degrees of claw asymmetry occur in more than 40% of the individuals. Environmental conditions contribute to the severity of the defect (technology, particularly the type of floor), but the disposition is genetically conditioned. Prevention should mainly be based on the negative selection of the carriers of the undesired disposition. Working on this study, we used the results of the population statistical processing of the reports on the hereditary defects of pigs and the results of our own observations. In the former case the data concerned 29,778 pig litters, in the latter case 7343 pigs of the Large White, Landrace, Duroc and Prestice Black-Pied breeds.
"In this paper I shall deal with the...official collection of demographic data in Liberal Italy, [with a focus on the]...political and theoretical aspects of the Italian statistics of the period." The study covers the nineteenth and early twentieth centuries.
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BACKGROUND: Available evidence suggests a peak in the incidence of cardiovascular events on Mondays compared to other days of the week. The exact magnitude of the excess risk and the role of age and gender, however, remain unclear. OBJECTIVE: To quantify the excess risk associated with the Monday peak in cardiovascular mortality and to explore the role of age and gender. METHODS: A meta-analysis of available published studies reporting on weekly patterns in incidence of myocardial infarction and sudden cardiac death was performed. RESULTS: Reports based on routinely collected data from population statistics (n = 5) generally reported a lower odds ratio (OR) of an event on Monday than studies with a confirmed diagnosis (n = 16). The pooled OR estimate based on population statistics was 1.04 (95%CI: 1.03; 1.05), whereas the pooled OR estimate based on confirmed diagnoses was 1.19 (95%CI: 1.17; 1.21). Subgroup analysis yielded an OR of 1.19 (95%CI: 1.07; 1.31) for men and 1.15 (95%CI: 0.99; 1.32) for women. Odds ratios for patients younger than 65 years of age and 65 or older were 1.22 (95%CI: 1.09; 1.36) and 1.16 (95%CI: 1.07; 1.27), respectively. The differences between subgroup odds ratios were not statistically significant. CONCLUSION: The incidence of sudden cardiac death is markedly increased on Monday, similar for men and women, and for subjects below and above 65 years of age.