Applying an Alpha Spending Function to an Observational Study for the Purpose of Accelerating the Assessment of a Healthcare Quality Improvement Initiative

Oregon Convention Center 

Alpha spending functions (ASFs) for randomized controlled trials (RCTs) control type I errors of interim analyses aimed to shorten study duration. Propensity score matching (PSM) in observational settings mimic RCTs to limit biases but can remain lengthy. This project's purpose is to assess potential benefits of applying ASF to a PSM study of a healthcare quality improvement initiative.
Blankenship (2022) published a 2-year PSM study assessing incident dialysis patients attending Transitional Care Units (TCU). The clinical outcomes assessed were either not statistically significant or significant with a positive association for TCUs.
This project divided the study into 8 quarters consisting of the patients and outcome information available at each look. PSM and statistical methods were performed as in the published analysis while additionally applying an ASF.
Applying ASF to the TCU study demonstrated key findings would have been determined in as little as 6 months. This, as well as additional previously unknown insights, reveal potential benefits of applying ASF to an observational program evaluation. Further research would inform if and how to apply ASFs to observational studies.

Alpha spending function

Observational study

Real world evidence

Propensity score matching

Longitudinal analysis

Group sequential design 

Health Policy Statistics Section