Preregistration: Definition, advantages, disadvantages, and how it can help against questionable research practices

Questionable research practices (QRPs), such as p-hacking (i.e., the inappropriate manipulation of data analysis to find statistical significance) and post hoc hypothesizing, are threats to the replicability of research findings. One key solution to the problem of QRPs is preregistration. This refers to time-stamped documentation that describes the methodology and statistical analyses of a study before the data are collected or inspected. As such, readers of the study’s report can evaluate whether the described research is in line with the planned methods and analyses or whether there are deviations from these (e.g., analyses performed so that the research hypotheses is confirmed). Here, we aim to describe what preregistration entails and why it is useful for psychology research. In this vein, we present the key elements of a sufficient preregistration file, its advantages as well as its disadvantages, and why preregistration is a key, yet partially insufficient, solution against QRPs. By the end of this chapter, we hope that readers are convinced that there is little reason not to preregister their research

Mortalidade por neoplasias no Brasil (1980/1983/1985): agrupamento dos Estados, comportamento e tendências Mortality from neoplasms in Brazil (1980/1983/1985): grouping by State, behaviors and tendencies

Examinou-se a mortalidade por neoplasias no Brasil, utilizando-se dados oficiais do Ministério da Saúde, abrangendo 26 Unidades da Federação e 13 diferentes localizações neoplásicas, para os anos de 1980, 1983 e 1985. As Análises de Agrupamento e de Componentes Principais revelaram comportamento heterogêneo entre regiões do país, com relação às 13 variáveis estudadas, sendo que os principais elementos discriminantes foram as neoplasias malignas da traquéia/brônquio/pulmão, seguidas das do estômago, esôfago, cólon e pâncreas. Análises complementares evidenciaram tendência de crescimento das taxas de mortalidade para as neoplasias malignas da próstata (17,74%), da traquéia/brônquio/pulmão(15,22%), da mama (11,32%), do pâncreas (10,23%), do cólon (8,08%), do colo uterino (6,45%) e da laringe (6,36%). Houve redução da mortalidade por neoplasias benignas/carcinoma "in situ"/ outras (27,37%), por neoplasias malignas no reto sigmóide/ânus (7,67%), do estômago (5,31%), de outro local do útero não especificado (2,56%), por leucemia (0,70%) e por neoplasias malignas do esôfago (0,44%). As neoplasias malignas do estômago foram a principal causa de morte por câncer no Brasil, representando 21,30% do total médio, seguidas das neoplasias malignas da traquéia/brônquio/pulmão(17,49% do total médio). Destacam-se os altos índices de mortalidade por neoplasias malignas do esôfago no Estado do Rio Grande do Sul.<br>Mortality caused by neoplasms in Brazil was examined by means of official Ministry of Health data covering 26 of the Federal Units and 13 different tumoral sites and referring to the years 1980,1983 and 1985. Both cluster analyses and those of principal components have shown heterogenous behaviour as between the different regions of the country in relation to the 13 variants studied. The main discriminatory elements are the trachea/bronchus/lung malign neoplasms followed by those of stomach, pancreas, colon and larynx. Complementary analyses have demonstrated a tendency to an increase in the mortality rate due to prostate malign neoplasms (17.74%), followed by those of trachea/bronchus/lung (15.22%), breast (11.32%), pancreas (10.23%), colon (8.08%), uterine colon (6.45%) and larynx (6.36). There has been a decrease of the mortality due to benign neoplasms/carcinoma "in situ "/others (27.37%), malign rectus neoplasms of the sigmoide/anus (7.67%), stomach (5.31%), of other non-specific locations in the uterus (2.56%), of leukaemia (0.70%) and malign neoplasms of the oesophagus (0.44%). Maling neoplasms of the stomach have been the main cause of cancer mortality in Brazil accounting for 21.27% of the mean total, followed by of the malign neoplasms trachea/bronchus/lung (17.52% of the general average). The mortality rates by esophageal malign neoplasms in Rio Grande do Sul is stressed