Berkson's Paradox

This parody (written by Greg Crowther) is sung to the tune of "Almost Paradise" (written by Eric Carmen and Dean Pitchford and performed by Mike Reno and Ann Wilson).

Context

A musical elaboration of a paradox, first described by Joseph Berkson, in which there seems to be a negative correlation between two desirable traits. It was written for a 2024 Renal Grand Rounds presentation by Leila Zelnick. (In this context, HbA1c refers to glycated hemoglobin, DAG refers to a Directed Acyclic Graph, ESRD refers to End-Stage Renal Disease, BMI refers to Body Mass Index, and RCT refers to a Randomized Clinical Trial.)

Lyrics

RESEARCH BRO:
I think I've made a great new discovery:
That putting on some weight
Helps HbA1c!

STATS QUEEN:
My friend, that relationship may be spurious!
If a patient is obese,

BOTH:
Or shows signs of disease,
The higher risk is the latter one of these!

Whoa, Berkson's Paradox:
Two arrows in a DAG collide!
Berkson's Paradox:
For analyses you've tried,
You'll need to keep selection bias in your thoughts,
(Or it's a) paradox!

RESEARCH BRO:
I found another advantage of obesity:
It helps you stay alive
When you have got ESRD!

STATS QUEEN:
No, not again -- my friend, you can't be serious!
The need to dialyze

BOTH:
Is more than BMIs,
And other things predict best who survives!

Whoa, Berkson's Paradox:
Selection bias sowing doubt!
Berkson's Paradox:
Think of those you're leaving out,
And those who start your RCT and then are lost,
(Or it's a) paradox!
(Collider bias will explain this) paradox!
(Use caution when you entertain this) paradox!

Other Files

• music video (with Leila Zelnick and Monty Harper)