Relative distribution analysis in Stata

In this article, I discuss the method of relative distribution analysis and present Stata software implementing various elements of the methodology. The relative distribution is the distribution of the relative ranks that the outcomes from one distribution take on in another distribution. The methodology can be used, for example, to compare the distribution of wages between men and women. The presented software, reldist, estimates the relative cumulative distribution and the relative density, as well as the relative polarization, divergence, and other summary measures of the relative ranks. It also provides functionality such as location and shape decompositions or covariate balancing. Statistical inference is implemented in terms of influence functions and supports estimation for complex samples.

Investigating the Use of Dry Matter Intake and Energy Balance Prepartum as Predictors of Digestive Disorders Postpartum

One objective was to evaluate the association of dry matter intake as a percentage of body weight (DMI%BW) and energy balance (EB) prepartum and postpartum, and energy-corrected milk (ECM) postpatum with digestive disorders postpartum. For this, ANOVA was used, and DMI%BW, EB, and ECM were the outcome variables, and left displaced abomasum (LDA), indigestion, and other digestive disorders (ODDZ) were the explanatory variables. The main objective was to evaluate prepartum DMI%BW and EB as predictors of digestive disorders. For this, logistic regression was used, and LDA, indigestion, and ODDZ were the outcome variables and DMI%BW and EB were the explanatory variables. Data from 689 cows from 11 experiments were compiled. Left displaced abomasum was not associated with prepartum DMI%BW or EB. Postpartum data were normalized to the day of the event (day 0). Cows that developed LDA had lesser postpartum DMI%BW on days −24, −23, −12, −7 to 0 and from days 1 to 8, 10 to 12, and 14 and 16, lesser postpartum EB from days −7 to −5, −3 to 0, and 12, and lesser postpartum energy-corrected milk on days −19, −2, −1, 0, 7, 9, 10, 15, and 17 relative to diagnosis than cows without LDA. Cows that developed indigestion had lesser prepartum DMI%BW and EB than cows without indigestion, and lesser postpartum DMI%BW on days −24, −1, 0, 1, and 2, and greater DMI%BW on day 26, lesser ECM on days −24, −2, −1, 0, 1, and 2 relative to diagnosis. Postpartum EB was not associated with indigestion postpartum. Cows that developed ODDZ had lesser prepartum DMI%BW on day −8 and from days −5 to −2, lesser prepartum EB on day −8 and from days −5 to −2, and lesser postpartum DMI%BW than cows without ODDZ. Each 0.1 percentage point decrease in the average DMI%BW and each Mcal decrease in the average EB in the last 3 days prepartum increased the odds of having indigestion by 9% each. Cutoffs for DMI%BW and EB during the last 3 days prepartum to predict indigestion were established and were ≤1.3%/day and ≤0.68 Mcal/day, respectively. In summary, measures of prepartum DMI%BW and EB were associated with indigestion and ODDZ postpartum and were predictors of indigestion postpartum, although the effect sizes were small.

Intersectional social-economic inequalities in breast cancer screening in India: analysis of the National Family Health Survey

Background Breast cancer incidence rates are increasing in developing countries including India. With 1.3 million new cases of cancer been diagnosed annually, breast cancer is the most common women’s cancer in India. India’s National Family Health Survey (NFHS-4) data 2015–2016 shows that only 9.8% of women between the ages of 15 and 49 had ever undergone breast examination (BE). Further, access to screening and treatment is unequally distributed, with inequalities by socio-economic status. It is unclear, however, if socio-economic inequalities in breast examination are similar across population subgroups. Methods We compared BE coverage in population sub-groups categorised by place of residence, religion, caste/tribal groups, education levels, age, marital status, and employment status in their intersection with economic status in India. We analysed data for 699,686 women aged 15–49 using the NFHS-4 data set conducted during 2015–2016. Descriptive (mean, standard errors, and confidence intervals) of women undergoing BE disaggregated by dimensions of inequality (education, caste/tribal groups, religion, place of residence) and their intersections with wealth were computed with national weights using STATA 12. Chi-square tests were performed to assess the association between socio-demographic factors and breast screening. Additionally, the World Health Organisation’s Health Equity Assessment Toolkit Plus was used to compute summary measures of inequality: Slope index for inequality (SII) and Relative Concentration Indices (RCI) for each intersecting dimension. Results BE coverage was concentrated among wealthier groups regardless of other intersecting population subgroups. Wealth-related inequalities in BE coverage were most pronounced among Christians (SII; 20.6, 95% CI: 18.5–22.7), married (SII; 14.1, 95% CI: 13.8–14.4), employed (SII: 14.6, 95%CI: 13.9, 15.3), and rural women (SII; 10.8, 95% CI: 10.5–11.1). Overall, relative summary measures (RCI) were consistent with our absolute summary measures (SII). Conclusions Breast examination coverage in India is concentrated among wealthier populations across population groups defined by place of residence, religion, age, employment, and marital status. Apart from this national analysis, subnational analyses may also help identify strategies for programme rollout and ensure equity in women’s cancer screening.

Towards Sustainability : Prioritizing Retrofit Options For Toronto's Single-Family Homes

This study investigates a preliminary retrofit ranking framework for single-family homes on the basis of net environmental effect. Four archetype homes developed to represent Toronto's existing housing stock were modeled using HOT2000 to calculate the operational energy requirements. The embodied effects of selected retrofits were then calculated using the ATHENA Impact estimator and a list of environmental summary measures produced. A method of combining operational and embodied effects based on these eight summary measures was proposed and the functioning and sensitivities of the equation were explored. The method is preliminary and incorporates two factors, a weighting factor and building science factor, that require further research. Analysis of the simultated results allowed generalizations about energy performance and prioritized retrofit recommendations for archetypes. In most retrofit cases operational energy dominates, however, the ranking equation shows the potential for certain conditions in which the embodied effects determine the ranking of a retrofit.

Towards Sustainability : Prioritizing Retrofit Options For Toronto's Single-Family Homes

This study investigates a preliminary retrofit ranking framework for single-family homes on the basis of net environmental effect. Four archetype homes developed to represent Toronto's existing housing stock were modeled using HOT2000 to calculate the operational energy requirements. The embodied effects of selected retrofits were then calculated using the ATHENA Impact estimator and a list of environmental summary measures produced. A method of combining operational and embodied effects based on these eight summary measures was proposed and the functioning and sensitivities of the equation were explored. The method is preliminary and incorporates two factors, a weighting factor and building science factor, that require further research. Analysis of the simultated results allowed generalizations about energy performance and prioritized retrofit recommendations for archetypes. In most retrofit cases operational energy dominates, however, the ranking equation shows the potential for certain conditions in which the embodied effects determine the ranking of a retrofit.

The consumer’s demand functions defined to study contingent consumption plans

Given two probability distributions expressing returns on two single risky assets of a portfolio, we innovatively define two consumer’s demand functions connected with two contingent consumption plans. This thing is possible whenever we coherently summarize every probability distribution being chosen by the consumer. Since prevision choices are consumption choices being made by the consumer inside of a metric space, we show that prevision choices can be studied by means of the standard economic model of consumer behavior. Such a model implies that we consider all coherent previsions of a joint distribution. They are decomposed inside of a metric space. Such a space coincides with the consumer’s consumption space. In this paper, we do not consider a joint distribution only. It follows that we innovatively define a stand-alone and double risky asset. Different summary measures of it characterizing consumption choices being made by the consumer can then be studied inside of a linear space over $${\mathbb {R}}$$ R . We show that it is possible to obtain different summary measures of probability distributions by using two different quadratic metrics. In this paper, our results are based on a particular approach to the origin of the variability of probability distributions. We realize that it is not standardized, but it always depends on the state of information and knowledge of the consumer.

A Rapid Motor Task-Based Screening Tool for Parkinsonism in Community-Based Studies

Background: The prevalence of parkinsonism in developing countries is largely unknown due to difficulty in ascertainment because access to neurologists is often limited.Objective: Develop and validate a parkinsonism screening tool using objective motor task-based tests that can be administered by non-clinicians.Methods: In a cross-sectional population-based sample from South Africa, we evaluated 315 adults, age >40, from an Mn-exposed (smelter) community, using the Unified Parkinson Disease Rating Scale motor subsection 3 (UPDRS3), Purdue grooved pegboard, and kinematic-UPDRS3-based motor tasks. In 275 participants (training dataset), we constructed a linear regression model to predict UPDRS3. We selected motor task summary measures independently associated with UPDRS3 (p < 0.05). We validated the model internally in the remaining 40 participants from the manganese-exposed community (test dataset) using the area under the receiver operating characteristic curve (AUC), and externally in another population-based sample of 90 participants from another South African community with only background levels of environmental Mn exposure.Results: The mean UPDRS3 score in participants from the Mn-exposed community was 9.1 in both the training and test datasets (standard deviation = 6.4 and 6.1, respectively). Together, 57 (18.1%) participants in this community had a UPDRS3 ≥ 15, including three with Parkinson's disease. In the non-exposed community, the mean UPDRS3 was 3.9 (standard deviation = 4.3). Three (3.3%) had a UPDRS3 ≥ 15. Grooved pegboard time and mean velocity for hand rotation and finger tapping tasks were strongly associated with UPDRS3. Using these motor task summary measures and age, the UPDRS3 predictive model performed very well. In the test dataset, AUCs were 0.81 (95% CI 0.68, 0.94) and 0.91 (95% CI 0.81, 1.00) for cut points for neurologist-assessed UPDRS3 ≥ 10 and UPDRS3 ≥ 15, respectively. In the external validation dataset, the AUC was 0.85 (95% CI 0.73, 0.97) for UPDRS3 ≥ 10. AUCs were 0.76–0.82 when excluding age.Conclusion: A predictive model based on a series of objective motor tasks performs very well in assessing severity of parkinsonism in both Mn-exposed and non-exposed population-based cohorts.

Summary measures of socioeconomic and area-based inequalities in fertility rates among adolescents: evidence from Ethiopian demographic and health surveys 2000–2016

Background One of the highest rates of adolescent pregnancies in the world is in sub-Saharan Africa. Most adolescent pregnancies in the region are unintended or unwanted, due to poor access to information and services on sexual and reproductive health for adolescents. Ethiopia has high adolescent fertility rates (AFR) with disparities across socioeconomic subgroups and regions. This study assessed the magnitude and trends of socioeconomic and area-based AFR inequalities in Ethiopia. Methods The 2000 and 2016 Ethiopia Demographic and Health surveys (EDHS) was analyzed using the World Health Organization’s (WHO) Health Equity Assessment Toolkit (HEAT) software. Adolescent fertility rates were disaggregated using three equity stratifiers (economic status, education and residence) and analyzed through four summary measures (Difference (D), Population Attributable Risk (PAR), Ratio (R) and Population Attributable Fraction (PAF)) to assess inequality. To measure statistical significance, point estimates were constructed using a 95% Uncertainty Interval (UI). Results Large socio-economic and urban-rural inequalities were observed within the 16-year period. Adolescents in less well-off socio-economic groups (PAF: -62.9 [95% UI; − 64.3, − 61.4], D: 96.4 [95% UI; 47.7, 145.1]), uneducated (R: 8.5 [95% UI; 4.8, 12.2], PAR: -76.4 [95% UI;-77.7, − 75.0]) and those from rural areas (D: 81.2 [95% UI; 67.9, 94.6], PAF: -74.2 [95% UI, − 75.7, − 72.7]) had a higher chance of pregnancy and more births than their counterparts. Conclusions Socioeconomic (education and economic status) and place of residence determine adolescents’ pregnancy and childbearing. Policies and programs should be directed at preventing child marriage and early fertility so that adolescents continue to access education, sexual and reproductive health care as well as access employment opportunities. More emphasis should be placed on subpopulations with disproportionately higher adolescent pregnancy and childbirth.