Pediatric screening urinalysis: a difference-in-differences analysis of how a 2007 change in guidelines impacted use

Table 2 Adjusted proportion of child visits including urinalysis before and after 2007, compared to young adult visits

Visit sample	Total unweighted visits (N)^a	Total weighted visits (N)^b	Before, 2005-2006 proportion of visits, % (95% CI^c)^d	After, 2008-2009 proportion of visits, % (95% CI)^d	Before-after difference,% (95% CI)	Difference-in-differences, % (95% CI)	P-value
Overall
Females and males
Children	2,151	80,088,667	20.4 (18.4, 22.5)	22.5 (21.9, 23.2)	2.1 (-0.3, 4.5)	-4.8 (-9.0, -0.5)	0.03
Young adults	868	23,244,921	20.1 (14.7, 25.5)	27.0 (23.7, 30.3)	6.9 (0.6, 13.2)	-4.8 (-9.0, -0.5)	0.03
Private practices
Females
Children	773	36,124,192	23.3 (14.6, 31.9)	22.5 (20.3, 24.7)	-0.7 (-9.8, 8.4)	-7.6 (-13.7, -1.5)	0.02
Young adults	379	15,179,624	20.4 (14.9, 25.9)	27.3 (24.9, 29.6)	6.9 (1.1, 12.7)	-7.6 (-13.7, -1.5)	0.02
Males
Children	875	40,420,271	18.3 (15.4, 21.2)	23.6 (21.4, 25.9)	5.4 (2.2, 8.5)	-0.5 (-10.6, 9.6)	0.93
Young adults	149	6,024,527	18.2 (11.8, 24.7)	24.1 (16.5, 31.6)	5.8 (-3.8, 15.5)	-0.5 (-10.6, 9.6)	0.93
Community health centers
Females
Children	271	1,823,073	29.2 (27.4, 30.9)	6.2 (3.3, 9.1)	-23.0 (-27.5, -18.4)	-17.4 (-27.9, -6.8)	0.001
Young adults	302	1,827,843	34.9 (31.8, 38.0)	29.3 (24.1, 34.5)	-5.6 (-12.8, 1.6)	-17.4 (-27.9, -6.8)	0.001
Males
Children	232	1,721,131	13.7 (4.6, 22.9)	5.6 (2.0, 9.1)	-8.2 (-18.1, 1.8)	-33.5 (-47.4, -19.7)	<0.001
Young adults	47	212,927	10.6 (10.2, 11.0)	36.0 (18.0, 54.0)	25.3 (7.7, 43.0)	-33.5 (-47.4, -19.7)	<0.001

^aUnweighted visits reflect the absolute number of visits in the study sample.
^bWeighted visits are sample visits weighted using NAMCS patient visit frequencies to develop national estimates.
^cCI = Confidence Interval.
^dEstimates are adjusted for continuous patient age, patient race/ethnicity (white, black, and other), and physician specialty (pediatrician or family practitioner).

ISSN: 1471-2431