Table 1.

Mean [95% CI] unadjusted scores of offspring behaviour scales according to whether or not the mother ate fish prenatally (subjects with prenatal mercury measures).

Age of child and behaviour score	Ate no fish		Did eat fish		All
	N	Mean [95% CI]	N	Mean [95% CI]	N	Mean [95% CI]
Total difficulties
Age 47ma (M)	356	9.23 [8.73, 9.72]	2285	8.39 [8.21, 8.57]	2776	8.55 [8.38, 8.72]
Age 81ma (M)	299	8.47 [7.88, 9.06]	2036	7.12 [6.92, 7.32]	2436	7.32 [7.13, 7.51]
Age 7–8ya (T)	223	6.55 [5.74, 7.36]	1287	5.25 [5.00, 5.55]	1692	5.64 [5.36, 5.91]
Age 10–11ya (T)	261	6.63 [5.90, 7.36]	1478	5.39 [5.10, 5.69]	1959	5.72 [5.46, 5.98]
Age 11–12ya (M)	244	7.46 [6.76, 8.16]	1730	6.12 [5.89, 6.34]	2062	6.36 [6.15, 6.57]
Age 13ya (M)	222	7.49 [6.81, 8.17]	1635	6.36 [6.13, 6.59]	1942	6.49 [6.28, 6.71]
Age 16–17y (M)	173	6.24 [5.50, 6.98]	1369	5.95 [5.70, 6.21]	1599	6.01 [5.78, 6.25]
Prosocial
Age 47m (M)	356	7.09 [6.88, 7.30]	2285	7.07 [6.99, 7.15]	2776	7.08 [7.01, 7.16]
Age 81m (M)	300	8.10 [7.90, 8.29]	2043	8.23 [8.16, 8.31]	2445	8.21 [8.14, 8.28]
Age 7–8ya (T)	223	7.54 [7.19, 7.88]	1286	7.91 [7.78, 8.04]	1690	7.81 [7.69, 7.93]
Age 10–11y (T)	261	7.67 [7.37, 7.96]	1478	7.87 [7.75, 8.00]	1959	7.80 [7.69, 7.91]
Age 11–12y (M)	244	8.14 [7.92, 8.37]	1730	8.37 [8.29, 8.45]	2062	8.33 [8.26, 8.40]
Age 13y (M)	225	8.01 [7.75, 8.26]	1642	8.23 [8.15, 8.31]	1952	8.21 [8.13, 8.28]
Age 16–17y (M)	223	7.85 [7.55, 8.14]	1375	8.02 [7.92, 8.12]	1608	8.01 [7.92, 8.10]
Hyperactive
Age 47ma (M)	356	4.02 [3.78, 4.25]	2285	3.74 [3.64, 3.83]	2776	3.79 [3.70, 3.87]
Age 81ma (M)	299	3.71 [3.41, 4.02]	2036	3.20 [3.10, 3.30]	2436	3.27 [3.18, 3.37]
Age 7–8ya (T)	223	2.78 [2.40, 3.15]	1288	2.29 [2.15, 2.43]	1693	2.45 [2.32, 2.58]
Age 10–11ya (T)	261	2.67 [2.32, 3.02]	1478	2.14 [2.01, 2.28]	1959	2.31 [2.19, 2.43]
Age 11–12ya (M)	244	2.95 [2.66, 3.25]	1729	2.63 [2.52, 2.73]	2061	2.70 [2.60, 2.79]
Age 13ya (M)	223	3.23 [2.93, 3.53]	1641	2.74 [2.64, 2.85]	1949	2.81 [2.71, 2.90]
Age 16–17y (M)	176	2.56 [2.23, 2.89]	1378	2.50 [2.39, 2.62]	1611	2.52 [2.42, 2.62]
Conduct
Age 47ma (M)	356	2.00 [1.86, 2.15]	2285	1.83 [1.77, 1.88]	2776	1.86 [1.81, 1.91]
Age 81ma (M)	300	1.80 [1.62, 1.98]	2044	1.55 [1.49, 1.61]	2446	1.59 [1.53, 1.65]
Age 7–8ya (T)	223	0.96 [0.73, 1.19]	1286	0.59 [0.52, 0.65]	1692	0.68 [0.62, 0.75]
Age 10–11ya (T)	261	1.12 [0.89, 1.35]	1478	0.79 [0.71, 0.87]	1959	0.89 [0.81, 0.96]
Age 11–12ya (M)	244	1.42 [1.23, 1.61]	1731	1.11 [1.05, 1.17]	2063	1.17 [1.11, 1.23]
Age 13ya (M)	225	1.40 [1.21, 1.58]	1640	1.14 [1.08, 1.21]	1950	1.18 [1.12, 1.23]
Age 16–17 (M)	178	0.97 [0.78, 1.15]	1376	0.94 [0.87, 1.01]	1611	0.95 [0.89, 1.01]
Emotional
Age 47 m (M)	356	1.43 [1.28, 1.58]	2285	1.37 [1.31, 1.43]	2776	1.40 [1.34, 1.45]
Age 81 m (M)	300	1.65 [1.46, 1.84]	2042	1.47 [1.40, 1.54]	2444	1.50 [1.44, 1.56]
Age 7–8ya (T)	223	1.56 [1.28, 1.84]	1288	1.26 [1.16, 1.36]	1693	1.33 [1.24, 1.42]
Age 10–11ya (T)	261	1.48 [1.24, 1.72]	1477	0.79 [0.71, 0.87]	1958	1.29 [1.20, 1.37]
Age 11–12y (M)	242	1.59 [1.35, 1.82]	1727	1.39 [1.31, 1.46]	2057	1.42 [1.35, 1.50]
Age 13y (M)	227	1.36 [1.13, 1.59]	1640	1.37 [1.28, 1.45]	1952	1.37 [1.29, 1.45]
Age 16–17y (M)	176	1.58 [1.29, 1.87]	1375	1.47 [1.37, 1.57]	1608	1.49 [1.39, 1.58]
Peer problems
Age 47ma (M)	356	1.78 [1.61, 1.95]	2285	1.45 [1.39, 1.51]	2776	1.51 [1.46, 1.57]
Age 81ma (M)	299	1.42 [1.24, 1.60]	2043	0.98 [0.92, 1.04]	2444	1.05 [0.99, 1.11]
Age 7–8y (T)	223	1.28 [1.05, 1.51]	1288	1.13 [1.04, 1.23]	1693	1.19 [1.10, 1.27]
Age 10–11y (T)	261	1.37 [1.16, 1.59]	1478	1.21 [1.12, 1.31]	1959	1.24 [1.16, 1.32]
Age 11–12ya (M)	244	1.51 [1.27, 1.75]	1733	1.02 [0.95, 1.09]	2065	1.09 [1.03, 1.16]
Age 13ya (M)	226	1.60 [1.35, 1.85]	1641	1.14 [1.06, 1.21]	1952	1.18 [1.11, 1.25]
Age 16–17y (M)	176	1.32 [1.04, 1.59]	1375	1.09 [1.01, 1.17]	1608	1.11 [1.04, 1.19]

M = Mother; T = Teacher assessment.

For all scales except the prosocial behaviour, the higher the score, the worse the behaviour.

^aDifferences between columns 1 and 2: P < 0.05.