Measures

6.2.1 Parental measures

Maternal and paternal psychological distress was measured in T1-T4, using the 36-item General Health Questionnaire (GHQ-36) by Goldberg and Hiller (1979). It is known to give an effective measure of mild psychiatric disorders – also conceptualized as psychological distress (e.g. Penninkilampi-Kerola, Miettunen, & Ebeling, 2006) – in the general population (Ferdinand & Verhulst, 1994). The items cover symptoms of depression (feelings of hopelessness and suicidal ideation), anxiety (feelings of being under constant pressure and panicking), sleeping difficulties (waking up at night and difficulties in falling asleep), and social dysfunction (feelings of inability to perform everyday tasks and social activities). Mothers and fathers estimated how well the descriptions matched their mental state over the past few weeks on a 4-point scale, ranging from 1 (not at all) to 4 (much more than usual). Cronbach’s α values for mean response scores (T1 - T4) ranged between .91 and .95 in both mothers and fathers. In addition, dichotomic variables of clinical significance were calculated, based on the clinical criterion of the cut-off point in Finnish samples (Holi, Marttunen, & Aalberg, 2003). The cut-off point is 9 and above after recoding the original values ranging between 1 and 4 into dichotomous values (the original values 1-2 = 0 and the original values 3-4 = 1).

Maternal and paternal depression was assessed at T1-T3 using a shortened version of Beck’s Depression Inventory (BDI-13) by Beck, Ward, Mendelsohn, Mock and Erlaugh (1961). The Finnish version of the BDI has been found valid and reliable in detecting depressive symptoms (Kaltiala-Heino, Rimpelä, & Laippala, 1999). BDI consists of 13 descriptions of low mood, hopelessness and somatic signs of depression. Mothers and fathers estimated their present state on a 5-point scale, ranging from 0 (symptom not present) to 4 (symptom present most of the time).

Cronbach’s α values for maternal and paternal mean response scores (T1-T3) ranged between .75 and .84. In addition, dichotomic variables of clinical significance were formed based on the clinical criterion of the cut-off point in Finnish samples (Kaltiala-Heino et al., 1999). The cut-off point for mild depression is 5 and above, after recoding the original values (the original values 0 and 1 = 0, the original value 2 = 1, 3 = 2, and 4 = 3).

Early fathering experience was assessed at T2-T3 using the short form of Parenting Stress Index (PSI-36; Abidin, 1995). It consists of three components: The parent

domain (12 items), describing the experience of one’s resources and limitations as a parent (e.g. ‘After having a child, I can hardly ever do the things that I would want to’). The interaction domain (12 items) represents the experience of the dyadic relationship with the child (e.g. ‘I often feel that my child doesn’t like me or wish to be near me’). The child domain (12 items) describes the experience of child’s early characteristics regarding easiness vs. demandingness from the caretaker’s point of view (e.g. ‘My child cries and fusses much more than other children’). Fathers estimated how the descriptions matched their experiences on a 5-point scale, ranging from 1 (completely agree) to 5 (completely disagree), with higher values indicating more positive experience. All three domains correlated at both time points (r’s ranging from .50 to .60, p < .01). Cronbach’s α values for mean response scores (T2-T3) ranged between .82 and .85.

6.2.2 Child measures

Both parents separately reported the child’s mental health and social and cognitive development at the age of 7-8 years, and the means of their assessments were calculated. In families where only one parental report was available (n = 209; 27.4%), the scales include only this report.

Children’s mental health symptoms were measured at T4 using the parent report scales of Behavioral Assessment System for Children (BASC; Reynolds &

Kamphaus, 1992), consisting of total of 12 symptom scales (138 items). Four scales were chosen for this study on the basis of representativeness and reliability for internalizing and externalizing problems: Anxiety (11 items) measures a child’s tendency to be nervous, fearful, or worried about real or imagined problems;

depression (12 items) represents a child’s experiences of sadness and stress with potential difficulty to carry out everyday activities; somatization (13 items) reflects a child’s alertness towards bodily sensations and a tendency to complain about relatively minor physical discomforts; and aggression (13 items) represents a child’s verbal or physical hostility towards others. Parents rated the child’s behavior on a 4-point response scale, ranging from 1 (never) to 4 (almost always). Cronbach’s α values for each mean response score ranged between .70 and .85. Maternal and paternal reports were significantly correlated for all scales, r range: .33 - .53, p < .01.

For the analyzes, we constructed mean score sum variables for internalizing symptoms (anxiety, depression and somatization scales). For externalizing symptoms, we used aggression mean score and also five items of attention problems

from the executive functions -domain of cognitive developmental problems from the Five to Fifteen questionnaire (described below) to represent a wider range of externalizing problems. Attention problems’ α:s were .81 and .78, and maternal and paternal reports correlated significantly, r = .61, p < .01. Cronbach’s α for combined maternal and paternal internalizing scale was .85 and externalizing scale .88.

Children’s social developmental problems were measured at T4 by a scale from Social Skills Rating System (SSRS) (Gresham & Elliot, 1990) and another from Child Behavior Scale (CBS) (Ladd & Profilet, 1996). Assertion-subscale of the SSRS (10 items) describes a child’s initiatives and ability to bond with peers, and peer exclusion -subscale of the CBS (seven items) measures a child’s popularity versus rejection among peers. Parents estimated how well the descriptions fit their child on a 4-point response scale, ranging from 1 (never) to 4 (almost always). Cronbach’s α values for mean response scores ranged between .78 and .80. Maternal and paternal reports were significantly correlated for both dimensions, r = .56 - .57, p < .01. For the analyses, we constructed a mean score of combined maternal and paternal evaluation of social developmental problems, which had a Cronbach’s α of .81.

Children’s cognitive developmental problems were assessed at T4 by the Five to Fifteen (FTF, Kadesjö et al., 2004) questionnaire for childhood neuropsychological symptoms, consisting in total of eight domains (181 items). Four domains were chosen for this study based on developmental considerations: executive functions (subdomain planning and organizing, seven items), perception (subdomains time concepts, body perception and visual perception, 13 items), memory (subdomains semantic and episodic memory and recall, 11 items) and language (subdomains expressive language skills and communication, 16 items). Parents rated the child’s behavior on a 3-point response scale, ranging from 1 (does not describe my child at all) to 3 (describes my child well). Maternal and paternal Cronbach’s α values for mean response scores ranged between .70 and .90. Maternal and paternal reports were significantly correlated for all domains, r range: .52 - .71, p < .01. Cronbach’s α values for combined parental mean scores ranged between .77 and .89.

Children’s psychophysiological-hormonal stress regulation was assessed at T5 by saliva cortisol samples. A research assistant visited families’ homes to train the parents and children to collect the samples. They collected five samples (C1-C5) during a regular school-day: immediately after awakening (C1), 30 minutes after awakening (C2), one hour after awakening (C3), after returning from school in late afternoon (C4), and before going to sleep in the evening (C5). The sampling tube consisted of a plastic sampling vessel with a suspended insert containing sterile neutral cotton wool swab.

The children were instructed to chew the swab for about a minute and then to return

it to the insert. The families made structured notes about the exact time of saliva collection and stored the samples in their refrigerator. At the following day, a research assistant took the samples to Helsinki University Central Hospital laboratory, where cortisol was analyzed by a relatively novel and sensitive method of liquid chromatography-tandem mass spectrometry (LC-MS/MS), operating in the negative mode electrospray ionization (ESI) after separation on a reversed-phase column (Turpeinen, Välimäki, & Hämäläinen, 2009). For the analyzes, we constructed a sum variable of cortisol secretion throughout the day (C1-C5).