MIMIC_IV creatinine_baseline MDRD est (units)

[aoifeboyle3004]

I am trying to group a patient cohort based on their eGFR on admission (group by mild/mod/severe renal imp)
Have reviewed the extremely useful creatinine_baseline table. All of the MDRD output in this does not reflect true eGFR values? Lot are in the 0.7 range - have tried to convert to umol/L but that is not correct either (have 0 patients with an eGFR score of <66ml/min)?

Any idea what the unit is for the MDRD_est - it is not in true eGFR?

[alistairewj]

Hmm odd, perhaps a mistake in the code? The MDRD_est column is meant to use the simple formula: eGFR = 186 × Scr^(-1.154) × Age^(-0.203) × 0.742(Female)

calculated here: https://github.com/MIT-LCP/mimic-code/blob/main/mimic-iv/concepts/measurement/creatinine_baseline.sql

mimic-code/mimic-iv/concepts/measurement/creatinine_baseline.sql

Lines 17 to 22 in 8cb6028

	, CASE WHEN p.gender = 'F' THEN
	POWER(75.0 / 186.0 / POWER(ag.age, -0.203) / 0.742, -1 / 1.154)
	ELSE
	POWER(75.0 / 186.0 / POWER(ag.age, -0.203), -1 / 1.154)
	END
	AS mdrd_est

[alistairewj]

Oh, right, this is an estimate of the baseline creatining using the MDRD formula in reverse. So.. this is just a poorly named column!

[aoifeboyle3004]

That makes far more sense!! Thank you - now to figure this one out :)