Table 2.

Mean number of steps per day (with 95 % CI) among boys and girls by grade level in Tokyo in 2011

			Total			Boys			Girls			Differences of steps per day between boys and girls
	Grade	Age	n	Mean steps per day	95 % CI	n	Mean steps per day	95 % CI	n	Mean steps per day	95 % CI		p value	d
All grades			15471	10338	10281–10395	7786	11262	11173–11351	7685	9402	9336–9468	1860	<0.001	0.513
Primary school	1	6–7	1564	11659	11504–11813	802	12575	12369–12781	762	10694	10482–10906	1881	<0.001	0.602
	2	7–8	1548	11641	11475–11806	772	12714	12491–12936	776	10573	10352–10795	2141	<0.001	0.644
	3	8–9	1565	11573	11406–11740	768	12736	12512–12961	797	10452	10232–10673	2284	<0.001	0.677
	4	9–10	1615	11336	11169–11503	828	12596	12381–12811	787	10010	9790–10231	2586	<0.001	0.758
	5	10–11	1591	10908	10740–11077	795	12302	12085–12519	796	9517	9300–9734	2785	<0.001	0.815
	6	11–12	1656	10612	10444–10781	853	12021	11807–12234	803	9117	8896–9337	2904	<0.001	0.831
Junior high school	1	12–13	1715	9674	9497–9850	877	10218	9974–10462	838	9104	8855–9353	1114	<0.001	0.299
	2	13–14	1529	9273	9092–9455	783	9830	9580–10080	746	8689	8433–8946	1141	<0.001	0.316
	3	14–15	1632	7887	7743–8031	816	8337	8136–8538	816	7437	7236–7638	900	<0.001	0.304
High school	1	15–16	374	8485	8147–8824	177	8583	8091–9075	197	8398	7932–8864	185	0.592
	2	16–17	374	8152	7828–8477	161	8322	7827–8816	213	8025	7595–8454	297	0.373
	3	17–18	308	8032	7692–8373	154	7935	7452–8417	154	8130	7647–8612	−195	0.574
(subclassification)
Primary school	1–3	6–9	4677	11624	11530–11718	2342	12674	12542–12806	2335	10571	10439–10703	2103	<0.001	0.642
	4–6	9–12	4862	10950	10853–11047	2476	12303	12175–12432	2386	9545	9414–9676	2758	<0.001	0.798
	1–6	6–12	9539	11280	11212–11348	4818	12483	12382–12584	4721	10053	9977–10129	2430	<0.001	0.718
Junior high school	1–3	12–15	4876	8950	8851–9049	2476	9476	9347–9604	2400	8408	8278–8539	1068	<0.001	0.302
High school	1–3	15–18	1056	8235	8042–8428	492	8294	8007–8582	564	8184	7915–8452	110	0.575

Differences between boys and girls tested with independent t-tests and Cohen’s ds were calculated to assess the size of intergroup differences