Predicting the direction of change in aggregate demand growth and its components

In this study, we set up a framework to generate the forecasts of growth in aggregate demand and its components using real-time data. In general, these forecasts (for 1983-2008) accurately predict directional change under symmetric loss and are thus of value to a user who assigns similar cost (loss) to incorrect upward and downward predictions. Our model is simple yet useful, especially to economically-rational agents who tend to balance the predictive benefit of a forecast against the cost of gathering and processing information. We conclude by suggesting that the success of our model may have to do with the stationary behavior of the series as well as monetary policy that aims to achieve sustainable growth with stable prices.Macroeconomy, Monetary policy, Naïve forecast, Directional accuracy, Asymmetric or symmetric loss

A Comparison of U.S. Housing Starts Forecasts

This study examines the Federal Reserve and private forecast accuracy of housing starts. We show that the Federal Reserve (private) forecasts are (generally) unbiased and superior to the random walk benchmark. At the shorter horizon, the Federal Reserve and private forecasts embody distinct predictive information, indicating that one can gain a significant improvement in forecast accuracy by combining the two sets of forecasts. At the longer horizon, our findings support the asymmetric information hypothesis that the Federal Reserve forecasts embody useful predictive information beyond that contained in the private forecasts.Greenbook forecasts; Survey of Professional Forecasters, Unbiasedness, Asymmetric information, Forecast combination

Are Preliminary Data Of Output Growth And Inflation Reliable Predictors?

The hypothesis that the preliminary announcements of output growth and inflation are reliable predictors of the revised data is tested for 1969.1-1991.4 and 1969.1-2000.4. Our test results indicate that these preliminary announcements are unbiased predictors. The output growth revision is orthogonal to the past revisions of both output growth and inflation available at the time of announcement. The inflation revision, however, fails to be orthogonal to such past revisions.  While unbiased, the lack of orthogonality of the inflation announcement suggests room for improvement

Forecasts of growth in US durables spending: assessing the usefulness of disaggregated consumer survey data

This study aims to improve the accuracy of the Federal Reserve forecasts of growth in durables spending using disaggregated consumer survey data. Test results for 1988–2016 indicate that these forecasts do (do not) contain past information in consumer durables-buying (home-buying) attitudes of 35–54-year-old participants, participants with a college degree, male participants, and participants with the top 33% income. Using real-time data on durables spending and information in consumer home-buying attitudes and expectations, we construct a knowledge model (KM) to generate comparable forecasts of growth in durables spending. Our results indicate that the one- and four-quarter-ahead KM forecasts can potentially help improve the accuracy of Federal Reserve forecasts. Further results indicate that the one- and fourquarter- ahead combined Federal Reserve and KM forecasts show significant reductions in forecast errors, meaning that there are accuracy gains from using disaggregated consumer survey data. The practical implication is that forecasters should pay special attention to consumer home-buying attitudes and expectations about future business conditions, and policymakers should make use of such survey measures in monitoring the economy in real time

The Highly Cited Systematic Review and Meta-Analysis Articles of Cardiac And Cardiovascular Systems: A Scientometric Study Based on Web of Science

Introduction: Systematic reviews and meta-analyses have been placed at the summit of the evidence pyramid in the evidence-based medicine paradigm. Scientometric investigation can provide useful insight into the field's scholarly communications. Therefore, this study is an attempt to scientometric study of the highly cited systematic reviews and meta-analysis articles of cardiac and cardiovascular systems category based on Web of Science. Methods: The study focused on those highly cited articles that were retrieved from Web of Science between July 20th and July 27th, 2019. After multiple phases of screening the retrieved articles, 150 articles formed the current research population. A number of articles in systematic review and meta-analysis, the publication trend, the status of authors' countries, authors’ affiliation, and the publication sources of the articles were examined. Results: Meta-analysis articles account for 52% of the research population. The largest share of the highly cited papers were for 2018. The results showed 61.3% of the studies conducted by international cooperation. The largest number of the studies have been conducted by researchers of USA, England, Netherland and Canada. The largest number of the articles published in American College of Cardiology, and European Heart Journal. The majority of the highly cited articles (79.33%) published in Q1 journals. Conclusion: The publication of the highly cited articles has benefited greatly from international collaboration. Researchers from of the United States, the Netherlands, England and Canada significantly contributed to the articles' production. The highly cited papers have been published in the most prestigious journals

Incidence rate of thyroid cancer in Iranian population, trend analysis from 2003 to 2009

Background and aims: Thyroid cancer is the most common endocrine malignant and papillary cancer and three times more prevalent in women than men. The aim of this study was to evaluate the incidence rate and trend of thyroid cancer in Iranian population. Methods: National incidence was rated by Iran National Cancer Registry data derived from Iran’s annual national cancer registration reported from 2003 to 2009. The crude rate and age standardized rate were used to express the incidence of thyroid cancer. Results: The results indicated that, the incidence of thyroid cancer increased from 2003 to 2009. The age standardized rate for women and men increased from 2.02 and 0.82 to 4.2 and 1.36 per 100,000, respectively. Conclusion: This study indicated remarkable increasing trends in thyroid cancer incidence. So, attention to high risk groups and public programs is necessary to reduce the incidence of this cancer in future

Considering time-interaction terms using parametric survival models for interval-censoring data

Background: Many of the variables which are investigated in survival research are time-invariant, i.e. their values do not change over time. But their effects, may yet vary over time. Thus, the change in behavior that occurs over time needs to be included in the analysis. This can be done by adding time-interaction terms to the model. Method: In this research, a parametric survival model, which is capable of evaluating the effects of time-dependent variables, was applied for interval-censored data such that the time to invariant variables interaction terms were considered as time-dependent variables. Results: Using a practical example, the results of the study show that this model can alter the interpretations regarding the effects of exploratory variables. Conclusion: when dealing with fixed variables whose effects change over time, the researcher can incorporate their interaction effect with time, and treat them as time-dependent variables and obtain appropriate inferences

Comparison of the effects of eicosapentaenoic acid with docosahexaenoic acid on the level of serum lipoproteins in helicobacter pylori: A randomized clinical trial

Background: Helicobacter pylori infection is the most common chronic bacterial infection around the world and an important cause of gastrointestinal disorders, which might be involved in the pathogenesis of some extragastrointestinal disturbances as well as changes in serum lipid profile. Hypolipemic properties of omega-3 fatty acids have been studied in several studies. Objectives: The present study aimed to compare the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation on the level of serum lipoproteins in H. pylori. Patients and Methods: In a randomized, double-blinded, placebo-controlled clinical trial in Iran, 105 Helicobacter pylori were randomly allocated to receive 2 g of daily EPA (35 patients), DHA (35 patients), or medium-chain triglyceride (MCT) oil as placebo (33 patients) along with conventional tetra-drug H. pylori eradication regimen for 12 weeks. Results: From 105 included patients, 97 (31 in EPA, 33 in DHA, and 33 in control groups) completed the study and were included in final analysis. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and the ratios of TG/HDL-C, TC/HDL-C, and LDL-C/HDL-C were not significantly different among the three groups, while the level of triglyceride (TG) was statistically different. DHA (-16.6 ± 30.34) and control (+ 15.32 ± 56.47) groups were statistically different with regard to changes in TG levels (P = 0.000). Conclusions: There was no difference between the effects of 2 g of EPA or DHA supplementation for 12 weeks on the levels of total cholesterol, LDL-C, HDL-C, TC/HDL-C, TG/HDL-C, and LDL-C/HDL-C; however, it had a desirable effect on the level of TG in a way that the effect of DHA was clearer. © 2015, Iranian Red Crescent Medical Journal

A Cure Rate Model with Discrete Frailty on Hodgkin Lymphoma Patients after Diagnosis

Introduction: Hodgkin lymphoma (HL) is an uncommon cancer of lymphocytes, characterized by cancerous Reed-Sternberg cells in an inflammatory background. HL is an exceptionally curable disease with combination chemotherapy, radiotherapy, or combined modality treatment. This analysis aimed to identify significant prognostic factors on the cure rate. Materials and Methods: The medical records of 110 patients hospitalized from 2007 up to 2014 with 18 months follow-up was retrospectively reviewed in Taleghani hospital of Tehran, Iran. The survival time was set as the time interval between diagnosis and a patient's death from HL. Also, if the cure rate was present in survival, data encompasses zero frailty. Thus, using hyper-Poisson (hP) distribution as discrete frailty, the unobserved heterogeneity and random effects were accounted for. Results: The estimated cure fraction was 81.2%, which was obtained after 2717 days (7.4 years). In noncured cases, the mean survival time was 1535 days (4.2 years). Also, the five and ten-year survival rates were 0.91 and 0.80, respectively. After diagnosis, results revealed that patients with age  45, hemoglobin  12, WBC  15000, and BMI  30 were associated with poor outcome by using simple analysis. More importantly, there is no significant difference between males and females in the cure of HL patients. Conclusion: As expected, the study indicated that a high proportion of HL patients got cured. A cure rate model with discrete frailty utilization provided a suitable way to account for heterogeneity among HL patients. &nbsp

A Comparison Between the Skills-Based Education with a Lecture-Based Education on Female Adolescents’ Knowledge, Attitude and Practice about Health in Puberty: A Randomized Trail Study

Abstract Introduction: Skills-based health education is useful in the promotion of health behaviors. Preparing for puberty is essential for adolescents. This study aimed to assess the effects of a skills-based education on girls' knowledge, attitudes, and practice about health in puberty. Methods: This was an experimental study on 80 female school students in Tehran, Iran. Two groups of forty participants were randomly designated as the experimental and control in two different high schools in Tehran. A skills-based education program trained the experimental group, and a routine lecture-based education taught the control group about health in puberty. Data was collected using a questionnaire that assessed the participants' knowledge, attitudes, and practice about health in puberty; before, immediately after, and two months after the education. Results: Knowledge and attitude were significantly improved in the skills-based education group comparing to the Lecture-based group, immediately after (P = 0.002 and P = 0.045, respectively) and two months after the interventions (P < 0.001 and P = 0.034, respectively). Both methods were not effective in improving practice. Conclusions: Skills-based health education is more effective than the routine lecture-based education on improving knowledge and attitudes about puberty in health