We have a lot of chances to use time-to-event (survival) analysis, especially in the biomedical and pharmaceutical fields. SAS^® provides the LIFETEST procedure to calculate Kaplan-Meier estimates for survival function and to delineate a survival plot. The PHREG procedure is used in Cox regression models to estimate the effect of predictors in hazard rates. Programs with ODS tables that are defined by PROC LIFETEST and PROC PHREG can provide more statistical information from the generated data sets. This paper provides a macro that uses PROC LIFETEST and PROC PHREG with ODS. It helps users to have a survival plot with estimates that include the subject at risk, events and total subject number, survival rate with median and 95% confidence interval, and hazard ratio estimates with 95% confidence interval. Some of these estimates are optional in the macro, so users can select what they need to display in the output. (Subject at risk and event and subject number are not optional.) Users can also specify the tick marks in the X-axis and subject at risk table, for example, every 10 or 20 units. The macro dynamic calculates the maximum for the X-axis and uses the interval that the user specified. Finally, the macro uses ODS and can be output in any document files, including JPG, PDF, and RTF formats.

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As you know, real world data (RWD) provides highly valuable and practical insights. But as valuable as RWD is, it still has limitations. It is encounter-based, and we are largely blind to what happens between encounters in the health-care system. The encounters generally occur in a clinical setting that might not reflect actual patient experience. Many of the encounters are subjective interviews, observations, or self-reports rather than objective data. Information flow can be slow (even real time is not fast enough in health care anymore). And some data that could be transformative cannot be captured currently. Select Internet of Things (IoT) data can fill the gaps in our current RWD for certain key conditions and provide missing components that are key to conducting Analytics of Healthcare Things (AoHT), such as direct, objective measurements; data collected in usual patient settings rather than artificial clinical settings; data collected continuously in a patient s setting; insights that carry greater weight in Regulatory and Payer decision-making; and insights that lead to greater commercial value. Teradata has partnered with an IoT company whose technology generates unique data for conditions impacted by mobility or activity. This data can fill important gaps and provide new insights that can help distinguish your value in your marketplace. Join us to hear details of successful pilots that have been conducted as well as ongoing case studies.

There are many good validation tools for Clinical Data Interchange Standards Consortium (CDISC) Study Data Tabulation Model (SDTM) such as Pinnacle 21. However, the power and customizability of SAS^® provide an effective tool for validating SDTM data sets used in clinical trials FDA submissions. This paper presents three distinct methods of using SAS to validate the transformation from Electronic Data Capture (EDC) data into CDISC SDTM format. This includes: duplicate programming, an independent SAS program used to transform EDC data with PROC COMPARE; rules checker, a SAS program to verify a specific SDTM or regulatory rules applied to SDTM SAS data sets; and transformation validation, a SAS macro used to compare EDC data and SDTM using PROC FREQ to identify outliers. The three examples illustrate the diverse approaches to applying SAS programs to catch errors in data standard compliance or identify inconsistencies that would otherwise be missed by other general purpose utilities. The stakes are high when preparing for an FDA submission. Catching errors in SDTM during validation prior to a submission can mean the difference between success or failure for a drug or medical device.

A Bayesian network is a directed acyclic graphical model that represents probability relationships and conditional independence structure between random variables. SAS^® Enterprise Miner implements a Bayesian network primarily as a classification tool; it includes na ve Bayes, tree-augmented na ve Bayes, Bayesian-network-augmented na ve Bayes, parent-child Bayesian network, and Markov blanket Bayesian network classifiers. The HPBNET procedure uses a score-based approach and a constraint-based approach to model network structures. This paper compares the performance of Bayesian network classifiers to other popular classification methods, such as classification tree, neural network, logistic regression, and support vector machines. The paper also shows some real-world applications of the implemented Bayesian network classifiers and a useful visualization of the results.

Regarding a human disease network, most studies have estimated the associations of disorders primarily with gene or protein information. Those studies, however, have some difficulties in the data because of the massive volume of data and the huge computational cost. Instead, we constructed a human disease network that can describe the associations between diseases, using the claim data of Korean health insurance. Through several statistical analyses, we show the applicability and suitability of the disease network. Furthermore, we develop a statistical model that can predict a prevalence rate for dementia by using significant associations of the network in a statistical perspective.

For all business analytics projects big or small, the results are used to support business or managerial decision-making processes, and many of them eventually lead to business actions. However, executives or decision makers are often confused and feel uninformed about contents when presented with complicated analytics steps, especially when multi-processes or environments are involved. After many years of research and experiment, a web reporting framework based on SAS^® Stored Processes was developed to smooth the communication between data analysts, researches, and business decision makers. This web reporting framework uses a storytelling style to present essential analytical steps to audiences, with dynamic HTML5 content and drill-down and drill-through functions in text, graph, table, and dashboard formats. No special skills other than SAS^® programming are needed for implementing a new report. The model-view-controller (MVC) structure in this framework significantly reduced the time needed for developing high-end web reports for audiences not familiar with SAS. Additionally, the report contents can be used to feed to tablet or smartphone users. A business analytical example is demonstrated during this session. By using this web reporting framework based on SAS Stored Processes, many existing SAS results can be delivered more effectively and persuasively on a SAS^® Enterprise BI platform.

The Analysis Data Model (ADaM) Basic Data Structure (BDS) can be used for many analysis needs. We all know that the SAS^® DATA step is a very flexible and powerful tool for data processing. In fact, the DATA step is very useful in the creation of a non-trivial BDS data set. This paper walks through a series of examples showing use of the SAS DATA step when deriving rows in BDS. These examples include creating new parameters, new time points, and changes from multiple baselines.

Detection and adjustment of structural breaks are an important step in modeling time series and panel data. In some cases, such as studying the impact of a new policy or an advertising campaign, structural break analysis might even be the main goal of a data analysis project. In other cases, the adjustment of structural breaks is a necessary step to achieve other analysis objectives, such as obtaining accurate forecasts and effective seasonal adjustment. Structural breaks can occur in a variety of ways during the course of a time series. For example, a series can have an abrupt change in its trend, its seasonal pattern, or its response to a regressor. The SSM procedure in SAS/ETS^® software provides a comprehensive set of tools for modeling different types of sequential data, including univariate and multivariate time series data and panel data. These tools include options for easy detection and adjustment of a wide variety of structural breaks. This paper shows how you can use the SSM procedure to detect and adjust structural breaks in many different modeling scenarios. Several real-world data sets are used in the examples. The paper also includes a brief review of the structural break detection facilities of other SAS/ETS procedures, such as the ARIMA, AUTOREG, and UCM procedures.

Creating an environment that enables and empowers self-service and agile analytic capabilities requires a tremendous amount of working together and extensive agreements between IT and the business. Business and IT users are struggling to know what version of the data is valid, where they should get the data from, and how to combine and aggregate all the data sources to apply analytics and deliver results in a timely manner. All the while, IT is struggling to supply the business with more and more data that is becoming available through many different data sources such as the Internet, sensors, the Internet of Things, and others. In addition, once they start trying to join and aggregate all the different types of data, the manual coding can be very complicated and tedious, can demand extraneous resources and processing, and can negatively impact the overhead on the system. If IT enables agile analytics in a data lab, it can alleviate many of these issues, increase productivity, and deliver an effective self-service environment for all users. This self-service environment using SAS^® analytics in Teradata has decreased the time required to prepare the data and develop the statistical data model, and delivered faster results in minutes compared to days or even weeks. This session discusses how you can enable agile analytics in a data lab, leverage SAS analytics in Teradata to increase performance, and learn how hundreds of organizations have adopted this concept to deliver self-service capabilities in a streamlined process.

The analysis of longitudinal data requires a model that correctly accounts for both the inherent correlation amongst the responses as a result of the repeated measurements, as well as the feedback between the responses and predictors at different time points. Lalonde, Wilson, and Yin (2013) developed an approach based on generalized method of moments (GMM) for identifying and using valid moment conditions to account for time-dependent covariates in longitudinal data with binary outcomes. However, the model developed using this approach does not provide information about the specific relationships that exist across time points. We present a SAS^® macro that extends the work of Lalonde, Wilson, and Yin by using valid moment conditions to estimate and evaluate the relationships between the response and predictors at different time periods. The performance of this method is compared to previously established results.

Would you like to be more confident in producing graphs and figures? Do you understand the differences between the OVERLAY, GRIDDED, LATTICE, DATAPANEL, and DATALATTICE layouts? Finally, would you like to learn the fundamental Graph Template Language methods in a relaxed environment that fosters questions? Great this topic is for you! In this hands-on workshop, you are guided through the fundamental aspects of the GTL procedure, and you can try fun and challenging SAS^® graphics exercises to enable you to more easily retain what you have learned.

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Do you need to add annotations to your graphs? Do you need to specify your own colors on the graph? Would you like to add Unicode characters to your graph, or would you like to create templates that can also be used by non-programmers to produce the required figures? Great, then this topic is for you! In this hands-on workshop, you are guided through the more advanced features of the GTL procedure. There are also fun and challenging SAS^® graphics exercises to enable you to more easily retain what you have learned.

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XML documents are becoming increasingly popular for transporting data from different operating systems. In the pharmaceutical industry, the Food and Drug Administration (FDA) requires pharmaceutical companies to submit certain types of data in XML format. This paper provides insights into XML documents and summarizes different methods of importing and exporting XML documents with SAS^®, including: using the XML LIBNAME engine to translate between the XML markup and the SAS format; creating an XML Map and using the XML92 LIBNAME engine to read in XML documents and create SAS data sets; and using Clinical Data Interchange Standards Consortium (CDISC) procedures to import and export XML documents. An example of importing OpenClinica data into SAS by implementing these methods is provided.

When analyzing data with SAS^®, we often use the SAS DATA step and the SQL procedure to explore and manipulate data. Though they both are useful tools in SAS, many SAS users do not fully understand their differences, advantages, and disadvantages and thus have numerous unnecessary biased debates on them. Therefore, this paper illustrates and discusses these aspects with real work examples, which give SAS users deep insights into using them. Using the right tool for a given circumstance not only provides an easier and more convenient solution, it also saves time and work in programming, thus improving work efficiency. Furthermore, the illustrated methods and advanced programming skills can be used in a wide variety of data analysis and business analytics fields.

Every organization, from the most mature to a day-one start-up, needs to grow organically. A deep understanding of internal customer and operational data is the single biggest catalyst to develop and sustain the data. Advanced analytics and big data directly feed into this, and there are best practices that any organization (across the entire growth curve) can adopt to drive success. Analytics teams can be drivers of growth. But to be truly effective, key best practices need to be implemented. These practices include in-the-weeds details, like the approach to data hygiene, as well as strategic practices, like team structure and model governance. When executed poorly, business leadership and the analytics team are unable to communicate with each other they talk past each other and do not work together toward a common goal. When executed well, the analytics team is part of the business solution, aligned with the needs of business decision-makers, and drives the organization forward. Through our engagements, we have discovered best practices in three key areas. All three are critical to analytics team effectiveness. 1) Data Hygiene 2) Complex Statistical Modeling 3) Team Collaboration

Prince Niccolo Machiavelli said things on the order of, The promise given was a necessity of the past: the word broken is a necessity of the present. His utilitarian philosophy can be summed up by the phrase, The ends justify the means. As a personality trait, Machiavelianism is characterized by the drive to pursue one's own goals at the cost of others. In 1970, Richard Christie and Florence L. Geis created the MACH-IV test to assign a MACH score to an individual, using 20 Likert-scaled questions. The purpose of this study was to build a regression model that can be used to predict the MACH score of an individual using fewer factors. Such a model could be useful in screening processes where personality is considered, such as in job screening, offender profiling, or online dating. The research was conducted on a data set from an online personality test similar to the MACH-IV test. It was hypothesized that a statistically significant model exists that can predict an average MACH score for individuals with similar factors. This hypothesis was accepted.

The EXPAND procedure is very useful when handling time series data and is commonly used in fields such as finance or economics, but it can also be applied to medical encounter data within a health research setting. Medical encounter data consists of detailed information about healthcare services provided to a patient by a managed care entity and is a rich resource for epidemiologic research. Specific data items include, but are not limited to, dates of service, procedures performed, diagnoses, and costs associated with services provided. Drug prescription information is also available. Because epidemiologic studies generally focus on a particular health condition, a researcher using encounter data might wish to distinguish individuals with the health condition of interest by identifying encounters with a defining diagnosis and/or procedure. In this presentation, I provide two examples of how cases can be identified from a medical encounter database. The first uses a relatively simple case definition, and then I EXPAND the example to a more complex case definition.

Multicollinearity can be briefly described as the phenomenon in which two or more identified predictor variables in a multiple regression model are highly correlated. The presence of this phenomenon can have a negative impact on the analysis as a whole and can severely limit the conclusions of the research study. This paper reviews and provides examples of the different ways in which multicollinearity can affect a research project, and tells how to detect multicollinearity and how to reduce it once it is found. In order to demonstrate the effects of multicollinearity and how to combat it, this paper explores the proposed techniques by using the Behavioral Risk Factor Surveillance System data set. This paper is intended for any level of SAS^® user. This paper is also written to an audience with a background in behavioral science or statistics.

Graphics are an excellent way to display results from multiple statistical analyses and get a visual message across to the correct audience. Scientific journals often have very precise requirements for graphs that are submitted with manuscripts. While authors often find themselves using tools other than SAS^® to create these graphs, the combination of the SGPLOT procedure and the Output Delivery System enables authors to create what they need in the same place as they conducted their analysis. This presentation focuses on two methods for creating a publication quality graphic in SAS^® 9.4 and provides solutions for some issues encountered when doing so.

This paper compiles information from documents produced by the U.S. Food and Drug Administration (FDA), the Clinical Data Interchange Standards Consortium (CDISC), and Computational Sciences Symposium (CSS) workgroups to identify what analysis data and other documentation is to be included in submissions and where it all needs to go. It not only describes requirements, but also includes recommendations for things that aren't so cut-and-dried. It focuses on the New Drug Application (NDA) submissions and a subset of Biologic License Application (BLA) submissions that are covered by the FDA binding guidance documents. Where applicable, SAS^® tools are described and examples given.

Bayesian inference has become ubiquitous in applied science because of its flexibility in modeling data and advances in computation that allow special methods of simulation to obtain sound estimates when more mathematical approaches are intractable. However, when the sample size is small, the choice of a prior distribution becomes difficult. Computationally convenient choices for prior distributions can overstate prior beliefs and bias the estimates. We propose a simple form of prior distribution, a mixture of two uniform distributions, that is weakly informative, in that the prior distribution has a relatively large standard deviation. This choice leads to closed-form expressions for the posterior distribution if the observed data follow a normal, binomial, or Poisson distribution. The explicit formulas are easily encoded in SAS^®. For a small sample size of 10, we illustrate how to elicit the mixture prior and indicate that the resulting posterior distribution is insensitive to minor misspecification of input values. Weakly informative prior distributions suitable for small sample sizes are easy to specify and appear to provide robust inference.

A recurring problem with large research databases containing sensitive information about an individual's health, financial, and personal information is how to make meaningful extracts available to qualified researchers without compromising the privacy of the individuals whose data is in the database. This problem is exacerbated when a large number of extracts need to be made from the database. In addition to using statistical disclosure control methods, this paper recommends limiting the variables included in each extract to the minimum needed and implementing a method of assigning request-specific randomized IDs to each extract that is both secure and self-documenting.

At the end of a project, many institutional review boards (IRBs) require project directors to certify that no personally identifiable information (PII) is retained by a project. This paper briefly reviews what information is considered PII and explores how to identify variables containing PII in a given project. It then shows a comprehensive way to ensure that all SAS^® variables containing PII have their values set to NULL and how to use SAS to document that this has been done.

Mediation analysis is a statistical technique for investigating the extent to which a mediating variable transmits the relation of an independent variable to a dependent variable. Because it is useful in many fields, there have been rapid developments in statistical mediation methods. The most cutting-edge statistical mediation analysis focuses on the causal interpretation of mediated effect estimates. Cause-and-effect inferences are particularly challenging in mediation analysis because of the difficulty of randomizing subjects to levels of the mediator (MacKinnon, 2008). The focus of this paper is how incorporating longitudinal measures of the mediating and outcome variables aides in the causal interpretation of mediated effects. This paper provides useful SAS^® tools for designing adequately powered studies to detect the mediated effect. Three SAS macros were developed using the powerful but easy-to-use REG, CALIS, and SURVEYSELECT procedures to do the following: (1) implement popular statistical models for estimating the mediated effect in the pretest-posttest control group design; (2) conduct a prospective power analysis for determining the required sample size for detecting the mediated effect; and (3) conduct a retrospective power analysis for studies that have already been conducted and a required sample to detect an observed effect is desired. We demonstrate the use of these three macros with an example.

Every visualization tells a story. The effectiveness of showing data through visualization becomes clear as these visualizations will tell stories about differences in US mortality using the National Longitudinal Mortality Study (NLMS) data, using the Public-Use Microdata Samples (PUMS) of 1.2 million cases and 122 thousand records of mortality. SAS^® Visual Analytics is a versatile and flexible tool that easily displays the simple effects of differences in mortality rates between age groups, genders, races, places of birth (native or foreign), education and income levels, and so on. Sophisticated analyses including logistical regression (with interactions), decision trees, and neural networks that are displayed in a clear, concise manner help describe more interesting relationships among variables that influence mortality. Some of the most compelling examples are: Males who live alone have a higher mortality rate than females. White men have higher rates of suicide than black men.

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Public water supplies contain disease-causing microorganisms in the water or distribution ducts. To kill off these pathogens, a disinfectant, such as chlorine, is added to the water. Chlorine is the most widely used disinfectant in all US water treatment facilities. Chlorine is known to be one of the most powerful disinfectants to restrict harmful pathogens from reaching the consumer. In the interest of obtaining a better understanding of what variables affect the levels of chlorine in the water, this presentation analyzed a particular set of water samples randomly collected from locations in Orange County, Florida. Thirty water samples were collected and their chlorine level, temperature, and pH were recorded. A linear regression analysis was performed on the data collected with several qualitative and quantitative variables. Water storage time, temperature, time of day, location, pH, and dissolved oxygen level were the independent variables collected from each water sample. All data collected was analyzed using various SAS^® procedures. Partial residual plots were used to determine possible relationships between the chlorine level and the independent variables. A stepwise selection was used to eliminate possible insignificant predictors. From there, several possible models for the data were selected. F-tests were conducted to determine which of the models appeared to be the most useful.

Bivariate Cox proportional models are used when we test the association between a single covariate and the outcome. The test repeats for each covariate of interest. SAS^® uses the last category as the default reference. This raises problems when we want to keep using 0 as our reference for each covariate. The reference group can be changed in the CLASS statement. But, if a format is associated with a covariate, we have to use the corresponding format instead of raw numeric data. This problem becomes even worse when we have to repeat the test and manually enter the reference every single time. This presentation demonstrates one way of fixing the problem using the MACRO function and SYMPUT function.

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