Unbiased Analysis of Today's Healthcare Issues

Statisitics and the Sports Illustrated Jinx

Daniel Kahneman explains the false inference many people make between causation and regression to the mean. A well-known example is the “Sports Illustrated jinx,” the claim that an athlete whose picture appears on the cover of the magazine is doomed to perform poorly the following season.  Overconfidence and the pressure of meeting high expectations are […]

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Test for equality of categorical varibles

In the standard statistics case, when you compare two continuous variables, you can use a t-test to determine equality of means.  For instance, you may want to know if LeBron James scores more points on average than Kevin Durant. However, what if you want to instead compare two categorical variables.  For instance, assume you are […]

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Mahalanobis Distance

What is Mahalanobis distance? Most people know what Euclidean distance is…it is the shortest distance between any two points.  In other words, its what we typically think of when we think of distance – the distance we would measure with a ruler, and the one given by the Pythagorean formula. Unlike Euclidean distance, Mahalanobis distance […]

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How Missing Data affects Physicians’ P4P Bonuses

Pay-for-performance programs often offer bonuses (or penalties) for physicians, hospitals and other providers based on the quality of care patients receive.  Measuring quality of care, however, is often difficult.  For chronic conditions, for instance, many patients eligible for outcome measures may be lost to follow-up.  This issue can potentially affect provider evaluations and bonus payments. […]

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CMS Chronic Conditions Dashboard

CMS has just released a new interactive tool that allows users to examine chronic conditions among Medicare beneficiaries. The CMS Chronic Conditions Dashboard presents statistical views of information on the prevalence, utilization and Medicare spending for Medicare beneficiaries with chronic conditions. The Dashboard displays information on a set of predefined chronic conditions available in the […]

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2011 National Health Expenditures

According to research from the CMS Office of the Actuary, healthcare spending growth is decelerating.  As published in Health Affairs:  In 2011 US health care spending grew 3.9 percent to reach $2.7 trillion, marking the third consecutive year of relatively slow growth. Growth in national health spending closely tracked growth in nominal gross domestic product (GDP) in 2010 […]

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Add to Your Skills Toolkit: Bootstrapping Confidence Intervals

In previous posts, I have explained how to create bootstrap estimates for a variety of statistics.  Doing so is fairly simple and involves a 3 step procedure: Step 1: Using the observe data, create m boostrap data sets by using  random resampling with replacement. Step 2: Calculate the statistic of interest for each bootstrap data […]

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Statistics from the Medicare Trustees Report

Basic Statistics In 2010, 47.5 million people were covered by Medicare: 39.6 million aged 65 and older, and 7.9 million disabled. About 25 percent of beneficiaries have chosen to enroll in Part C private health plans that contract with Medicare to provide Part A and Part B health services. Total benefits paid in 2010 were […]

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Biases

All economists are familiar with the problem of selection bias.  In non-randomized samples, patients may choose to be in either the treatment or control group based on factors which are also related to the outcome of interest.  Even if researchers can design a study that fully controls for selection bias, robust studies must also account […]

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Medicare Dashboards

For which drugs does Medicare spend the most money?  For which inpatient hospital treatments does Medicare have the highest expenses.  CMS’s new Dashboards provide an easy to use source to access these high level summary statistics.  You can find this information here: Medicare Inpatient Hospital Dashboard (website, description) Medicare Prescription Drug Benefit Dashboard (website, description) […]

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