Table 2.

Correlation between the renal uptake rate at 1-2 min and that at 2-3 min after injecting the radiotracer.

Obstruction	Uptake rate	Uncorrected by bladder radioactivity			Corrected by bladder radioactivity			Correlation improvement after correction
		n 1	r	P	n 2	r	P
No obstruction	Total kidney	40	0.911	<0.001	35	0.974	<0.001	Improved
	Left kidney	40	0.865	<0.001	35	0.952	<0.001	Improved
	Right kidney	40	0.936	<0.001	35	0.967	<0.001	Improved
Right ureteral obstruction	Total kidney	171	0.907	<0.001	123	0.975	<0.001	Improved
	Left kidney	171	0.859	<0.001	123	0.979	<0.001	Improved
	Right kidney	171	0.967	<0.001	123	0.968	<0.001	No improvement

Notes: n₁—number of dynamic renal scintigraphy scans presenting the partial or entire bladder in the field of view; n₂—number of dynamic renal scintigraphy scans presenting the partial or entire bladder in the field of view and having no bladder radiotracer uptake at 1-2 min or 2-3 min plus those presenting the entire bladder in the field of view and having bladder-tracer uptake at 1-2 min or 2-3 min.