Table 2.

Relation between abdominal pain and childhood personality and behaviour and school absences

Risk factor (assessor)	No exposed	No (%) affected	Odds ratio (95% CI)*	lr χ2 for trend; P value
Neuroticism on Pintner personality inventory
Non-neurotic	1183	21 (1.8)	1.00	0.99; 0.32
Mid-neurotic	1042	19 (1.8)	1.07 (0.50 to 2.25)
Neurotic	1026	23 (2.2)	1.34 (0.67 to 2.68)
Introversion on Pinter personality inventory
Introvert	975	24 (2.5)	1.00	0.57; 0.45
Ambivert	1104	17 (1.5)	0.83 (0.40 to 1.68)
Extravert	1172	22 (1.9)	0.79 (0.39 to 1.60)
Energy level at age 13 (teacher)
Never tired	233	1 (0.4)	1.00	1.82; 0.18
Normally energetic	3026	62 (2.1)	2.48 (0.34 to 18.12)
Always tired	187	5 (2.7)	3.33 (0.37 to 30.08)
Day dreaming in class at age 13 (teacher)
Seldom or never	1664	25 (1.5)	1.00	4.77; 0.03
Sometimes	1602	36 (2.3)	1.55 (0.84 to 2.87)
Frequently	212	8 (3.8)	2.37 (0.88 to 6.33)
Disobedience in class at age 13 (teacher)
Seldom or never	3145	64 (2.0)	1.00	0.74; 0.4
Sometimes	321	321 (0.9)	0.45 (0.19 to 1.02)
Frequently	26	2 (7.7)	2.90 (0.77 to 10.93)
Lying in class at age 13 (teacher)
Seldom or never	2926	55 (1.9)	1.00	0.04; 0.83
Sometimes	483	13 (2.7)	1.36 (0.61 to 2.60)
Frequently	49	1 (2.0)	0.36 (0.05 to 2.71)
Periods of absence (weeks) at ages 6-10 (school doctor)
0-2	855	14 (1.6)	1.00	5.3; 0.02
3-4	717	9 (1.3)	0.61 (0.22 to 1.69)
5-8	851	22 (2.6)	1.66 (0.76 to 3.66)
⩾9	622	19 (3.1)	1.75 (0.77 to 4.01)
School absence at age 13 (teacher)
Seldom or never	824	12 (1.5)	1.00	2.24; 0.13
Sometimes	888	13 (1.5)	1.07 (0.41 to 2.79)
Frequently	851	24 (2.8)	1.71 (0.70 to 4.14)

lr = likelihood ratio test.  

^*Odds ratios corrected for sex and father’s social class, weighted for sampling.