Coexistence and prevalence of obstetric interventions: an analysis based on the grade of membership

Background Obstetric interventions performed during delivery do not reflect improvements in obstetric care. Several practices routinely performed during childbirth, without any scientific evidence or basis - such as Kristeller maneuver, routine episiotomy, and movement or feeding restriction - reflect a disrespectful assistance reality that, unfortunately, remains in place in Brazil. The aims of the current study are to assess the coexistence and prevalence of obstetric interventions in maternity hospitals in Belo Horizonte City, based on the Grade of Membership (GoM) method, as well as to investigate sociodemographic and obstetric factors associated with coexistence profiles generated by it. Methods Observational study, based on a cross-sectional design, carried out with data deriving from the study “Nascer em Belo Horizonte: Inquérito sobre o Parto e Nascimento” (Born in Belo Horizonte: Survey on Childbirth and Birth). The herein investigated interventions comprised practices that are clearly useful and should be encouraged; practices that are clearly harmful or ineffective and should be eliminated; and practices that are inappropriately used, in contrast to the ones recommended by the World Health Organization. The analyzed interventions comprised: providing food to parturient women, allowing them to have freedom to move, use of partogram, adopting non-pharmacological methods for pain relief, enema, perineal shaving, lying patients down for delivery, Kristeller maneuver, amniotomy, oxytocin infusion, analgesia and episiotomy. The current study has used GoM to identify the coexistence of the adopted obstetric interventions. Variables such as age, schooling, skin color, primigravida, place-of–delivery financing, number of prenatal consultations, gestational age at delivery, presence of obstetric nurse at delivery time, paid work and presence of companion during delivery were taken into consideration at the time to build patients’ profile. Results Results have highlighted two antagonistic obstetric profiles, namely: profile 1 comprised parturient women who were offered diet, freedom to move, use of partogram, using non-pharmacological methods for pain relief, giving birth in lying position, patients who were not subjected to Kristeller maneuver, episiotomy or amniotomy, women did not receive oxytocin infusion, and analgesia using. Profile 2, in its turn, comprised parturient women who were not offered diet, who were not allowed to have freedom to move, as well as who did not use the partograph or who were subjected to non-pharmacological methods for pain relief. They were subjected to enema, perineal shaving, Kristeller maneuver, amniotomy and oxytocin infusion. In addition, they underwent analgesia and episiotomy. This outcome emphasizes the persistence of an obstetric care model that is not based on scientific evidence. Based on the analysis of factors that influenced the coexistence of obstetric interventions, the presence of obstetric nurses in the healthcare practice has reduced the likelihood of parturient women to belong to profile 2. In addition, childbirth events that took place in public institutions have reduced the likelihood of parturient women to belong to profile 2. Conclusion(s) Based on the analysis of factors that influenced the coexistence of obstetric interventions, financing the hospital for childbirth has increased the likelihood of parturient women to belong to profile 2. However, the likelihood of parturient women to belong to profile 2 has decreased when hospitals had an active obstetric nurse at the delivery room. The current study has contributed to discussions about obstetric interventions, as well as to improve childbirth assistance models. In addition, it has emphasized the need of developing strategies focused on adherence to, and implementation of, assistance models based on scientific evidence.

Why not both? Rethinking categorical and continuous approaches to bilingualism

Aims and Objectives: Bilingualism is a complex construct, and it can be difficult to define and model. This paper proposes that the field of bilingualism can draw from other fields of psychology, by integrating advanced psychometric models that incorporate both categorical and continuous properties. These models can unify the widespread use of bilingual and monolingual groups that exist in the literature with recent proposals that bilingualism should be viewed as a continuous variable. Approach: In the paper, we highlight two models of potential interest: the factor mixture model and the grade-of-membership model. These models simultaneously allow for the formation of different categories of speakers and for continuous variation to exist within these categories. We discuss how these models could be implemented in bilingualism research, including how to develop these models. When using either of the two models, researchers can conduct their analyses on either the categorical or continuous information, or a combination of the two, depending on which is most appropriate to address their research question. Conclusions: The field of bilingualism research could benefit from incorporating more complex models into definitions of bilingualism. To help various subfields of bilingualism research converge on appropriate models, we encourage researchers to pre-register their model selection and planned analyses, as well as to share their data and analysis scripts. Originality: The paper uniquely proposes the incorporation of advanced statistical psychometric methods for defining and modeling bilingualism. Significance: Conceptualizing bilingualism within the context of these more flexible models will allow a wide variety of research questions to be addressed. Ultimately, this will help to advance theory and lead to a fuller and deeper understanding of bilingualism.

A Signal Detection Model for Multiple-Choice Exams

A model for multiple-choice exams is developed from a signal-detection perspective. A correct alternative in a multiple-choice exam can be viewed as being a signal embedded in noise (incorrect alternatives). Examinees are assumed to have perceptions of the plausibility of each alternative, and the decision process is to choose the most plausible alternative. It is also assumed that each examinee either knows or does not know each item. These assumptions together lead to a signal detection choice model for multiple-choice exams. The model can be viewed, statistically, as a mixture extension, with random mixing, of the traditional choice model, or similarly, as a grade-of-membership extension. A version of the model with extreme value distributions is developed, in which case the model simplifies to a mixture multinomial logit model with random mixing. The approach is shown to offer measures of item discrimination and difficulty, along with information about the relative plausibility of each of the alternatives. The model, parameters, and measures derived from the parameters are compared to those obtained with several commonly used item response theory models. An application of the model to an educational data set is presented.

Climate Profiles in Brazilian Microregions

Brazil’s territory is considerably large and characterized by a variety of climate patterns, which allows the identification of regional climate specificities. The objective of this study was to identify a typology of climatic characteristics for the microregions of Brazil using the grade of membership (GoM) method, which is a multivariate technique based on the fuzzy sets theory. The meteorological variables used were: precipitation (mm), relative humidity (%), maximum and minimum temperature (°C) and wind speed (m/s), obtained from the interpolated database elaborated by Xavier comprising the period from January 1981 to December 2013. Three predominant homoclimatic profiles were found. The GoM method also allowed the identification of five mixed profiles, which is unprecedent in studies in Brazil and corroborates the regional climate diversity in the country. Furthermore, the heterogeneities of Brazilian climates could be better outlined. The extreme profiles—“predominant 1—P1”, “predominant 2—P2” and “predominant 3—P3”—accounted for 42.9% (236) of the total microregions. Additionally, approximately half (53.9%) of the microregions were classified as featuring characteristics of at least two profiles—that is, they presented mixed profiles with hybrid characteristics. These hybrid microregions were located mostly at transition zones between climates.

Performance of the Grade of Membership Model Under a Variety of Sample Sizes, Group Size Ratios, and Differential Group Response Probabilities for Dichotomous Indicators

Social scientists are frequently interested in identifying latent subgroups within the population, based on a set of observed variables. One of the more common tools for this purpose is latent class analysis (LCA), which models a scenario involving k finite and mutually exclusive classes within the population. An alternative approach to this problem is presented by the grade of membership (GoM) model, in which individuals are assumed to have partial membership in multiple population subgroups. In this respect, it differs from the hard groupings associated with LCA. The current Monte Carlo simulation study extended on prior work on the GoM by investigating its ability to recover underlying subgroups in the population for a variety of sample sizes, latent group size ratios, and differing group response profiles. In addition, this study compared the performance of GoM with that of LCA. Results demonstrated that when the underlying process conforms to the GoM model form, the GoM approach yielded more accurate classification results than did LCA. In addition, it was found that the GoM modeling paradigm yielded accurate results for samples as small as 200, even when latent subgroups were very unequal in size. Implications for practice were discussed.

Perfis de integração social entre idosos institucionalizados não frágeis no município de Natal, Rio Grande do Norte, Brasil

Resumo O objetivo do estudo foi caracterizar idosos não frágeis em Instituições de Longa Permanência para Idosos (ILPI) em Natal, enfatizando a integração social em instituições filantrópicas e privadas. Os dados foram de pesquisa realizada em 2012. O instrumento utilizado foi o Brazil Old Age Schedule (BOAS). Realizou-se análise descritiva e, posteriormente, foram estimados perfis sociodemográficos e de saúde dos idosos a partir do método Grade of Membership (GoM) que permitiu identificar tipologias de integração social. Os achados indicaram que dos 68 idosos elegíveis, 63,2% eram do sexo feminino e 51,5% tinham 80 anos ou mais; 43% reportaram saúde ruim ou péssima. O método GoM caracterizou 3 perfis: um com maior presença de homens sociáveis/integrados, residentes em ILPI filantrópicas (22% dos idosos); outro, de mulheres isoladas em ILPI filantrópicas com condições vulneráveis de saúde e depressão (34,9%); um terceiro, de idosos sociáveis/integrados em ILPI particulares com boas condições de saúde, mas com fragilidade funcional e mais velhos (34,9%). O tema do estudo é relevante pois a institucionalização deveria manter ou até mesmo estimular a integridade e a independência do idoso em todos os aspectos da vida social dentro e fora da instituição.