Unbiased Analysis of Today's Healthcare Issues
If you are evaluating the treatment effect of a policy or medical intervention, does it matter if some of your subjects leave the sample? In many cases, the answer is ‘yes’. The Problem As outlined in Grasdal (2001), the effect of the treatment is simply: Δ = E(Y|X, T=1) − E(Y|X, T=0) However, in some…
On Saturday, UCSD Economics Professor Dr. Hal White passed away after an extended struggle with cancer. This is a sad day as Hal was one of my former professors. Here is an except from obituary written by Dr. Jim Hamilton regarding Dr. White’s work. Hal was one of the world’s leading econometricians. One of his core beliefs…
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…
Suppose you look at health care spending in two different regions and observe a significant difference. You may want to know what the cause of this difference is. Is it because one region has a mix of people who are sicker; or is because the reason treat patients with a given disease more intensively? One…
Many researchers use household data sources to examine a variety of hypothesis. The use of household data has many benefits including allowing for more detailed socioeconomic information (e.g., education, income) beyond what is contained in administrative claims files. One drawback of household data is that extrapolations made from household survey data may not match national…
Many research studies aim to figure out if a physicians did a good job. Many studies use administrative claims data to evaluate performance. Other times, researchers use medical record review. One problem with medical record review is that oftentimes experts will come up with differing opinions from reviewing the same medical record. Thus, researchers often…
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…
Understanding quantiles is fairly intuitive. A physician would rank in the τth quantile of in terms of quality of care if he performs better than the proportion τ of the reference group of physicians and worse than the proportion (1–τ). For physicians at the median, half of physicians will perform worse than this doctor and…
How does one determine if a test is accuracy? What does accuracy mean? One measure of test precision it is the positive predictive value, or the share of positive test results which are actually positive. Alternatively, the negative predictive value determines the share of negative test results which are true (rather than false) negatives. Better positive and…
How do ecologists determine the size of a population? One method is the mark and recapture (a.k.a. capture/recapture method). This method relies on having two separate trials to capture (either physically or in data) members of certain population and determines the population size based on the proportion of specimens who are captured in both…