. 2015 Sep 2;10(9):e0137238. doi: 10.1371/journal.pone.0137238

Table 1. Relative age distribution of junior playersin English Lower-League soccer clubs.

Age Category	Q1	Q2	Q3	Q4	N	Q1 v Q4 OR (CI)	Q2 v Q4 OR (CI)	Q3 v Q4 OR (CI)	1st v 2nd Half OR (CI)
All Players	48.6	24.6	17.7	9.2	1212	5.28 (4.08–6.83)^*	2.67 (2.04–3.50)^*	1.92 (1.46–2.54)^*	2.72 (2.22–3.34)
U9	42.74	29.91	19.66	7.69	117	5.56 (2.31–13.33)^*	3.89 (1.59–9.51)^*	2.56 (1.01–6.45)^*	2.66 (1.38–5.11)^*
U10	51.64	18.85	18.85	10.66	122	4.85 (2.22–10.57)^*	1.77 (0.76–4.12)	1.77 (0.76–4.12)	2.39 (1.27–4.51)^*
U11	46.09	22.61	19.13	12.17	115	3.79 (1.73–8.29)^*	1.86 (0.81–4.26)	1.57 (0.67–3.66)	2.19 (1.15–4.20)^*
U12	36.07	32.79	18.85	12.30	122	2.93 (1.36–6.35)^*	2.67 (1.23–5.80)^*	1.53 (0.67–3.49)	2.21 (1.18–4.16)^*
U13	46.15	22.31	23.08	8.46	130	5.45 (2.44–12.21)^*	2.64 (1.13–6.15)^*	2.73 (1.17–6.35)^*	2.17 (1.18–4.00)^*
U14	46.27	29.10	16.42	8.21	134	5.64 (2.53–12.55)^*	3.55 (1.56–8.07)^*	2.00 (0.84–4.76)	3.06 (1.65–5.69)^*
U15	56.25	21.88	11.72	10.16	128	5.54 (2.57–11.93)^*	2.15 (0.95–4.89)	1.15 (0.47–2.81)	3.57 (1.87–6.81)^*
U16	53.85	21.98	15.38	8.79	91	6.13 (2.38–15.79)^*	2.50 (0.92–6.83)	1.75 (0.62–4.98)	3.14 (1.48–6.66)^*
U17	39.55	31.34	13.43	15.67	134	2.52 (1.26–5.06)^*	2.00 (0.98–4.07)	0.86 (0.39–1.89)	2.44 (1.33–4.47)^*
U18	47.06	22.69	14.29	15.97	119	2.95 (1.42–6.10)^*	1.42 (0.65–3.09)	0.89 (0.39–2.05)	2.31 (1.21–4.38)^*

Table Notes: Q1 = % of N (total players in category) born between Sept-Nov of annual age cut-off dates, Q2 = Dec-Feb, Q3 = March-May, Q4 = June-August; 1^st Half = % of N born between Sept-Feb; 2^nd Half = Mar-August; OR = Odds Ratio calculation, (CI) = 95% Confidence Interval.

* = Significant finding ≤ 0.05.