Knowledge and Data Management White Papers
%QLS SAS Macro: A SAS Macro for Analysis of Longitudinal Data Using Quasi-Least Squares
Overview Quasi-Least Squares (QLS) is an alternative computational approach for estimation of the correlation parameter in the framework of Generalized Estimating Equations (GEE). QLS allows for easier implementation of some correlation structures that are not available for GEE. The paper describe a user-written SAS macro called %QLS, and demonstrate application of the macro using a clinical trial example for the comparison of two treatments for a common toenail infection. %QLS also computes the lower and upper boundaries of the correlation parameter for analysis of longitudinal binary data that were described by Prentice (Biometrics 44 (1988), 1033 - 1048). Furthermore, it displays a warning message if the Prentice constraints are violated.
| Publisher | SAS Institute | File Format | |
|---|---|---|---|
| Date Published | February 2009 | ||
| Format | White Papers | ||
| Topics | |||
-
Did you find this white paper useful?
White Paper RSSAccelerating Enterprise Data Governance Part 1
DownloadIn the first of this series of three white papers, Mike Ferguson of Intelligent Business Strategies defines what data governance is and then looks at the requirements that need to...
Data Governance for Master Data Management and Beyond
There is growing interest on behalf of both data management professionals and senior business managers to understand the motivations, mechanics, and benefits of instituting data governance within an organization. This...
Getting Started with Master Data Management
Master data management forms part of an overall enterprise governance program that aims to establish trusted data throughout the enterprise. This white paper from Mike Ferguson of Intelligent Business Strategies...
Five Steps to More Valuable Enterprise Data
Companies worldwide struggle with inconsistent, inaccurate or unreliable data - and often don't know how to build more useful corporate information. This white paper examines a five-step method for...
3 Strategies for Reducing IT Support Costs
As companies brace for more bumps in the economic downturn, many organisations are indiscriminately cutting costs. To ensure a seamless transition into the post-recession market, however, slashing and burning is...
