Table 2

Stepwise negative binomial regression model for the association between baseline variables and consultations during the following year for men and women.

Variable	Incidence rate ratio (95% CI)	Z	P-value
Females
IAS illness behaviour	1.71 (1.37 to 2.11)	4.816	<0.001
Physical chronic illness^a	1.72 (1.44 to 2.05)	5.999	<0.001
GHQ-12	1.21 (1.05 to 1.38)	2.583	<0.01
Psychiatric chronic illness^a	1.45 (1.12 to 1.87)	2.849	0.004
Somatic symptom score	1.45 (1.09 to 4.04)	2.229	0.026
Males
IAS illness behaviour	2.32 (1.74 to 3.11)	5.725	<0.001
Somatic symptom score	2.88 (1.57 to 5.28)	3.415	0.001
Physical chronic illness^a	1.39 (1.06 to 1.81)	2.389	0.017
IAS health anxiety	1.23 (1.02 to 1.49)	2.199	0.028

↵a no chronic illness as reference group. GHQ-12 = 12 item version of the General Health Questionnaire. IAS = Illness Attitude Scale. Associations are expressed as incidence rate ratios. For categorical variables the relative increase in consultation is expressed in relation to a reference group. For continuous variables the incidence rate ratio has been expressed as the relative increase in consultation per 10-unit change of the continuous variable (5-unit change for the Somatic Symptom Scale). The potential scoring range for continuous variables: GHQ-12 0–36, IAS health anxiety 0–44, IAS illness behaviour, somatic symptom score 0-7, age 23–71 year).