Wellcome Open Research
F1000 Research Limited
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Traumatic childhood events of parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC)
Volume: 5
DOI 10.12688/wellcomeopenres.15804.1
Abstract

Background: Early life experiences can have a significant impact on an individual’s later behaviour, the way they view the world, their beliefs and their success at forming strong interpersonal relationships. These factors may subsequently influence the way that the individual may parent their children, which in turn may have an effect on their child’s behaviour, mental health and world view. Research has linked early traumatic life experiences in the parent’s childhood to disorganised attachment to their own child. In this paper we describe the data collected from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) on traumatic events experienced during their childhood, so that it can act as a resource for researchers in the future when considering outcomes on the adult, their children and grandchildren.

Methods: Data were collected via multiple questionnaires completed by parents enrolled into the ALSPAC study. During pregnancy and post-delivery, questionnaires were administered between 1990 and 1992 via post to the study mothers and their partners. Data were collected on life events including bereavement, sexual abuse, physical abuse, abandonment, neglect, memories of childhood and accidents. Other reports of traumatic events in childhood were reported by parents using free text. This can be made available to researchers for coding on request.

Keywords
Ellis, Iles-Caven, Northstone, and Golding: Traumatic childhood events of parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC)

Introduction

In creating the ALSPAC resource, the research team included questions designed to examine childhood experiences of trauma for the study mothers, their partners and the offspring. This paper focuses on the data collected on the childhoods of the mother and her partner.

Psychological trauma is a complex psychological state resulting from life events that are physically or emotionally harmful and have lasting adverse effects on wellbeing. It is believed that these effects can be passed down intergenerationally to the children of trauma sufferers in the form of relational trauma 1.

Traumatic events can include (but are not limited to) events such as war/conflict, childhood physical and sexual abuse, natural disasters, traumatic accidents, illness or witnessing events that result in death, threaten death, serious injury or a threat to the physical integrity of self or others 2. The symptoms resulting long after the trauma has occurred can include depression, anger, anxiety, dissociative disorders and posttraumatic stress disorder (PTSD) 3.

Whilst we were able to find a large amount of research into the effects of trauma during childhood, and into the effects on the children of parents who experience trauma in adulthood, there is much less research on the effects on the children of parents who have suffered trauma in childhood.

The research that has been carried out to date regarding the relationship between childhood trauma and the impact it has on the offspring of those who experience childhood trauma, is predominantly centred around PTSD caused by parental neglect, domestic or sexual abuse 4, 5 and war 6, 7.

However, there appear to be fewer research papers available regarding parental childhood trauma from other sources such as natural disasters 8, illness 9, extreme poverty 10, accidental injury 11, loss of a parent 12 or sibling, or being a witness to a distressing event 13 .

Fisher et al. (2013)14, studied data from ALSPAC and found an association between adverse early life experiences, harsh parenting and bullying, and psychotic symptoms in the study children. The researchers used variables relating to the child’s lifestyle and life events as reported by the study mother, and evaluated the child’s early environment and bullying data, self-reported by the child to test for adversity. They then evaluated the child’s neurocognitive and psychological markers using these measures: Locus of Control gathered using a 12 item version of the Nowicki-Strickland Internal-External scale (NSIE) 15, self-esteem using a shortened form of Harter’s Self Perception Profile for Children 16, affective symptoms using the Development and Wellbeing Assessment (DAWBA) 17 and the Short Moods and Feelings Questionnaire (SMFQ) 18 both completed by the child’s parents, and finally, 12 core questions from the semi-structured psychosis interview (PLIKSi) 19. Fisher et al. concluded that harsh parenting was not a factor for psychotic symptoms in the child but was indicated in depressive symptoms, anxiety, external locus of control and low self-esteem. It would be interesting to see whether the parent exhibiting the harsh behaviour also suffered from these symptoms as a result of similar or other traumatic experiences during their own childhoods and whether there is a link to intergenerational trauma here.

Plant et al. (2018)20 analysed 9,397 ALSPAC mother child dyads with the aim of examining whether children whose mothers had a history of childhood trauma, were at increased risk of exhibiting psychopathology. The researchers tested three main hypotheses, that maternal child maltreatment (defined as whether the mother had been maltreated as a child) would predict child internalising and externalising difficulties, that maternal antenatal depression, maternal postnatal depression, maternal maladaptive parenting and child maltreatment would operate as independent mediators and finally, that there would be an indirect effect of maternal postnatal depression through maladaptive parenting and child maltreatment demonstrating separate cumulative effects. The researchers measured whether the mother had experienced physical abuse, sexual abuse, emotional abuse or neglect during their childhood (defined as <18 years). If the mother answered ‘yes’ to any of these exposures, they were considered to have experienced childhood maltreatment. They also measured whether the mothers showed signs of depression (antenatally and postnatally) using the Edinburgh Postnatal Depression Scale (EPDS) 21; and tested for symptoms of maladaptive parenting such as shouting, slapping and feelings of hostility towards their child. Child maltreatment (physical, sexual or emotional abuse) was elicited through maternal self-report. At 8 years of age the children were asked to self-report whether they had been bullied by their peers. The child was considered to have experienced maltreatment if a positive response had been given to any of these questions. Child depressive symptoms were measured at ages 10 and 13 by asking the mothers to complete the Development and Wellbeing Assessment (DAWBA) 17 and at 11 years, the Strengths and Difficulties (SDQ) 22 questionnaire. The researchers then looked at symptoms of attention-deficit hyperactivity disorder (ADHD), conduct disorder and oppositional defiant disorder (ODD), and found that maternal childhood maltreatment directly predicted the study child being exposed to maltreatment and subsequently developing psychopathology. This effect was greater when tested alongside maternal depression. Children of maltreated mothers had significantly greater emotional and behavioural difficulties at the ages of 10, 11 and 13, as well as greater peer conduct difficulties and hyperactivity problems. Maternal antenatal depression, postnatal depression and child maltreatment had an effect of independent mediation of the association between maternal child maltreatment and both internalising and externalising behaviour difficulties. Maladaptive parenting did not show this result.

In this paper we describe the data collected from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) on traumatic events experienced during their childhood, so that it can act as a resource for researchers in the future when considering outcomes on the adult, their children and grandchildren.

Methods

Participants

14,541 pregnant mothers’ resident in the former Avon county of South West England were recruited into the ALSPAC study. These mothers all had an expected delivery date of 1 st April 1991 to 31 st December 1992. From these pregnancies, there were a total of 14,676 fetuses and 14,062 live births. Of these children, 13,988 were still alive at 1 year of age. Mothers were considered enrolled if they had returned at least one questionnaire or attended a “Children in Focus” clinic by 19 th July 1999. At the age of 7, the study team reached out to mothers who had previously not been included in the study and recruited additional families in order to boost the number of participants. As such, from the age of 7 the total sample number is 15,454 live births, resulting in 15,589 foetuses, of which 14,901 alive at 1 year of age 23, 24. However, these additional parents did not have data collected on their own childhood exposures.

In order to protect the confidentiality of the sample, data from triplet and quad multiple births have been removed as these children were considered to be at risk of identification. This leaves 14,691 eligible participants remaining. ALSPAC is continuing to monitor these families and are recruiting the Children of the Children of the 90’s 25. The ALSPAC team continue to gather data concerning the parents and grandparents of the study children, enabling further intergenerational research.

Following the advice of the ALSPAC Ethics and Law Committee, partners were recruited into the study only if the mothers wished them to be included. Questionnaires were sent to the mother who then passed the questionnaire on to the partner with a separate pre-paid return envelope. This method meant that ALSPAC were unable to follow up or communicate directly with the partners 24, 26. Therefore, the numbers of partners’ questionnaires returned were less than those received for the mother’s questionnaires. Around 75% of the partners participated in the study.

Data collection

Since its inception, the ALSPAC study has collated thousands of variables from the study children and their families using questionnaires and clinics to collect the data.

This paper focuses on the variables we identified as being indicative of maternal childhood trauma experiences. There were 186 maternal variables which were collected from the A, B, C and D questionnaires, and 160 variables from the Partner’s collected via the PA, PB and PF questionnaires (Copies of these questionnaires can be viewed on the ALSPAC website). The variable naming convention for these questionnaires usually follows the format of the questionnaire’s assigned alphabetical letter followed by the number of the variable allocated in a sequential pattern in the data set.

The first four questionnaires were sent out at specific time points based on the mother’s gestation at enrolment. Partners were also surveyed at the mother’s discretion. The questionnaires were sent to the mother and the mother decided whether or not to pass that questionnaire to the partner.

Provided the mother enrolled before 14 weeks gestation, questionnaire A “Your Environment” and PA “You and Your Environment” were sent out on enrolment. If the mother enrolled after 14 weeks, the questionnaire was not sent until 22 weeks gestation. This was to prevent the mother feeling overwhelmed with questionnaires and to avoid clashes with the Having a Baby and Your Pregnancy questionnaires which were confined to certain gestation periods. In total, the Your Environment questionnaire was sent to 45% of participants before 15 weeks gestation, 32% between 22–25 weeks gestation and 23% were sent out later than 25 weeks.

Questionnaire B “Having a Baby” was sent out from 18 weeks gestation until 23 weeks gestation. If the mother enrolled before 24 weeks gestation, she also received the PB “Partners Questionnaire” alongside the B questionnaire. If the mother enrolled after 24 weeks, the PB “Partners Questionnaire” was sent out with the mothers “Your Home and Lifestyle” questionnaire. The “Your Home and Lifestyle” questionnaire is a version of the A “Your Environment” questionnaire which has been adapted for use by mothers who enrolled later into the study and therefore this data is coded alongside the A questionnaire data.

Questionnaire C “Your Pregnancy” was sent out from 32 weeks gestation until 40 weeks gestation. For questionnaire D “About Yourself” the timing of when this questionnaire was considered to be less important and therefore the bulk of these were sent out from 14 weeks gestation until 37 weeks gestation. However, in a small number of cases, questionnaire D was sent after the birth of the study child.

The H “Your Health Events and feelings” questionnaire was sent to mothers at 33 months postpartum and was accompanied by the PF “Partners Health Events and Feelings” questionnaire.

Please note that the study website contains details of all the data that is available through a fully searchable data dictionary and variable search tool.

The ALSPAC team have also provided a Questionnaire Topic guide which summarises the topics in each questionnaire.

The majority of the other questions available were drawn up by either the ALSPAC team or the European Longitudinal Study of Pregnancy and Childhood (ELSPAC) team. However, where suitable established measures existed, these measures were used within the questionnaire, occasionally with minor modifications.

Sample demographics

Table 1a and Table 1b show the demographics of the parents who completed the questionnaires that contained the childhood events and circumstances. Most of these questionnaires (B, C, D, PA and PB) were completed during pregnancy, H and PF were administered 33 months after the birth of the child. The tables show the range of ages, education level, and ethnicity of the participating parents.

Table 1a.
Demographic backgrounds of mothers who completed the B, C, D and H questionnaires.
NB
Questionnaire
NC
Questionnaire
ND
Questionnaire
NH
Questionnaire
Age of mother at
birth of child (e695)
<25
25–34
35+


11,503


2,314 (20.12%)
7,978 (69.36%)
1,211 (10.53%)


11,307


2,224 (19.67%)
7,875 (69.65%)
1,208 (10.68%)


11,286


2,222 (19.69%)
7,870 (69.73%)
1,194 (10.58%)


9,287


1,597(17.20%)
6,649 (71.59%)
1,041 (11.21%)
Mother’s highest
education level
(c645)
<O level
O level
>O level


11,447


2,863 (25.01%)
4,241 (37.05%)
4,343 (37.94%)


11,708


2,979 (25.44%)
4,324 (36.93%)
4,405 (37.62%)


11,168


2,750 (24.62%)
4,144 (37.11%)
4,274 (38.27%)


9,029


1,969 (21.81%)
3,347 (37.07%)
3,713 (41.12%)
Partner lives with
mother (a504)
Yes
No


12,976


11,797 (90.91%)
1,179 (9.09%)


12,272


11,231 (91.52%)
1,041 (8.48%)


12,364


11,316 (91.52%)
1,048 (8.48%)


9,579


8,880 (92.70%)
699 (7.30%)
Sex of child (kz021)
Male
Female


13,269


6,853 (51.65%)
6,416 (48.35%)


12,546


6,480 (51.65%)
6,066 (48.35%)


12,535


6,450 (51.46%)
6,085 (48.54%)


9,738


5,008 (51.43%)
4,730 (48.57%)
Mother’s Ethnic
background (c800)
White
Non-white


12,102


11,791 (97.43%)
311 (2.57%)


12,066


12,066 (97.37%)
326 (2.63%)


11,774


11,492 (97.60%)
282 (2.40%)


9,420


9,242 (98.11%)
178 (1.89%)
Table 1b.
Demographic backgrounds of partners who completed the PA, PB and PF questionnaires.
NPA QuestionnaireNPB QuestionnaireNPF Questionnaire
Age of partner at birth
(pc996)
<25
25–34
35+


6,638


623 (9.39%)
4,500 (67.79%)
1,515 (22.82%)


7,138


707 (9.90%)
4,808 (67.36%)
1,623 (22.74%)


4,657


325 (6.98%)
3,171 (68.09%)
1,161 (24.93%)
Partner’s highest education
level (pb325)
<O level
O level
<O level


7,533


1,763 (23.40%)
1,820 (24.16%)
3,950 (52.44%)


9,333


2,357 (25.25%)
2,238 (23.98%)
4,738 (50.77%)


4,953


987 (19.93%)
1,157 (23.36%)
2,809 (56.71%)


Partner lives with Mother
(a504)
Yes
No


8,616


8,219 (95.39%)
397 (4.61%)


9,857


9,355 (94.91%)
502 (5.09%)


5,456


5,267 (96.54%)
189 (3.46%)


Sex of child (kz021)
Boy
Girl


8,706


4,440 (51.00%)
4,266 (49.00%)


10,040


5,161 (51.40%)
4,879 (48.60%)


5,513


2,842 (51.55%)
2,671 (48.45%)


Partner’s Ethnic background
(pb440)
White
Non-white


7,902


7,715 (97.63%)
187 (2.37%)


9,910


9,622 (97.09%)
288 (2.91%)


5,113


5,030 (98.38%)
83 (1.62%)

Scale of life events

The life events questions to the mother ( Table 2a) comprised a set of 31 specific questions based on the previous work of Coddington 27 , regarding events that may or may not have happened to the respondent before the age of 17. These questions were included in the questionnaire C sent to the mother at around 32 weeks gestation. 30 similar questions were also sent to the mother’s partners in their own questionnaire administered during pregnancy, the question to the mothers concerning whether they had acquired a stepsibling was inadvertently omitted from the partner’s questionnaire ( Table 2b). For each specified item the respondent was asked to choose between five possible answers: ‘ yes, affected me a lot’; ‘ yes, moderately affected’; ‘ yes, mildly affected’; ‘ yes, but did not affect me’; ‘ no, did not happen’. For each parent a question concerning anything else that occurred was asked, with a description written as text; these responses are not included here.

Table 2a.
Mothers Life Events Scale indicating the potentially traumatic events that had occurred to the mother before 17 years of age, using questions based on Coddington 4 with the mother’s indication as to what effect they had had on her.
Variable
Number
QuestionCategorical responsesBinary responses
NYes,
big
effect
Yes,
moderate
effect
Yes,
mild
effect
Yes, no
effect
NoYesNo
Please indicate if any of the
following events happened to
you before you were 17 and how
much it affected you
c400Your parent died.12,291509
(4.14%)
110
(0.89%)
65
(0.53%)
45
(0.37%)
11,562
(94.07%)
c400aYour parent died.12,291729
(5.93%)
11,562
(94.07%)
c401Your brother or sister died.12,291129
(1.05%)
54
(0.44%)
51
(0.41%)
65
(0.53%)
11,992
(97.57%)
c401aYour brother or sister died.12,291299
(2.43%)
11,992
(97.57%)
c402A relative died.12,291878
(7.14%)
1,462
(11.89%)
2,452
(19.95%)
1,694
(13.78%)
5,805
(47.23%)
c402aA relative died.12,2916,486
(52.77%)
5.805
(47.23%)
c403A friend died.12,291269
(2.19%)
476
(3.87%)
744
(6.05%)
244
(1.99%)
10,558
(85.90%)
c403aA friend died.12,2911,733
(14.10%)
10,558
(85.90%)
c404A parent had a serious illness.12,291845
(6.87%)
628
(5.11%)
515
(4.19%)
198
(1.61%)
10,105
(82.21%)
c404aA parent had a serious illness.12,2912,186
(17.79%)
10,105
(82.21%)
c405A parent was in hospital.12,291988
(8.04%)
1,033
(8.40%)
1,406
(11.44%)
1,314
(10.69%)
7,550
(61.43%)
c405aA parent was in hospital.12,2914,741
(38.57%)
7,550
(61.43%)
c406You had a serious physical
illness.
12,291175
(1.42%)
152
(1.24%)
143
(1.16%)
120
(0.98%)
11,701
(95.20%)
c406aYou had a serious physical
illness.
12,291590
(4.80%)
11,701
(95.20%)
c407You were in hospital.12,291376
(3.06%)
621
(5.05%)
1,079
(8.78%)
1,971
(16.04%)
8,244
(67.07%)
c407aYou were in hospital.12,2914,047
(32.93%)
8,244
(67.07%)
c408Brother or sister had a serious
illness.
12,291203
(1.65%)
236
(1.92%)
277
(2.25%)
210
(1.71%)
11,365
(92.47%)
c408aBrother or sister had a serious
illness.
12,291926
(7.53%)
11,365
(92.47%)
c409Brother or sister was in hospital.12,291244
(1.99%)
377
(3.07%)
721
(5.87%)
1,243
(10.11%)
9,706
(78.97%)
c409aBrother or sister was in hospital.12,2912,585
(21.03%)
9,706
(78.97%)
c410A parent had a serious accident.12,291141
(1.15%)
127
(1.03%)
139
(1.13%)
100
(0.81%)
11,784
(95.88%)
c410aA parent had a serious accident.12,291507
(4.12%)
11,784
(95.88%)
c411You had a serious accident.12,29198
(0.80%)
104
(0.85%)
145
(1.18%)
94
(0.76%)
11,850
(96.41%)
c411aYou had a serious accident.12,291441
(3.59%)
11,850
(96.41%)
c412Brother or sister had a serious
accident.
12,291132
(1.07%)
143
(1.16%)
170
(1.38%)
116
(0.94%)
11,730
(95.44%)
c412aBrother or sister had a serious
accident.
12,291561
(4.56%)
11,730
(95.44%)
c413You acquired a physical
deformity.
12,29134
(0.28%)
20
(0.16%)
25
(0.20%)
15
(0.12%)
12,197
(99.24%)
c413aYou acquired a physical deformity.12,29194
(0.76%)
12,197
(99.24)
c414You became pregnant.12,291454
(3.69%)
152
(1.24%)
140
(1.14%)
177
(1.44%)
11,368
(92.49%)
c414aYou became pregnant.12,291923
(7.51%)
11,368
(92.49%)
c415A parent was imprisoned.12,29124
(0.20%)
15
(0.12%)
20
(0.16%)
33
(0.27)
12,199
(99.25)
c415aA parent was imprisoned.12,29192
(0.75%)
12,199
(99.25%)
c416A parent was physically cruel to
you.
12,291183
(1.49%)
120
(0.98%)
84
(0.68%)
34
(0.28%)
11,870
(96.57%)
c416aA parent was physically cruel to
you.
12,291421
(3.43%)
11,870
(96.57%)
c417Your parents separated.12,291829
(6.74%)
570
(4.64%)
398
(3.24%)
300
(2.44%)
10,194
(82.94%)
c417aYour parents separated.12,2912,097
(17.06%)
10,194
(82.94%)
c418Your parents divorced.12,291680
(5.53%)
496
(4.04%)
377
(3.07%)
342
(2.78%)
10,396
(84.58%)
c418aYour parents divorced.12,2911,895
(15.42%)
10,396
(84.58%)
c419A parent remarried.12,291367
(2.99%)
336
(2.73%)
306
(2.49%)
422
(3.43%)
10,860
(88.36%)
c419aA parent remarried.12,2911,431
(11.64%)
10,860
(88.36%)
c420A parent was emotionally cruel to
you.
12,291390
(3.17%)
264
(2.15%)
231
(1.88%)
53
(0.43%)
11,353
(92.37%)
c420aA parent was emotionally cruel to
you.
12,291938
(7.63%)
11,353
(92.37%)
c421Your parents had serious
arguments.
12,291843
(6.86%)
883
(7.18%)
1,060
(8.62%)
506
(4.12%)
8,999
(73.22%)
c421aYour parents had serious
arguments.
12,2913,292
(26.78%)
8,999
(73.22%)
c422You were sexually abused.12,291368
(2.99%)
131
(1.07%)
93
(0.76%)
36
(0.29%)
11,663
(94.89%)
c422aYou were sexually abused.12,291628
(5.11%)
11,663
(94.89%)
c423A parent was mentally ill.12,291167
(1.36%)
145
(1.18%)
142
(1.16%)
63
(0.51%)
11,774
(95.79%)
c423aA parent was mentally ill.12,291517
(4.21%)
11,774
(95.79%)
c424You discovered you were
adopted.
12,29148
(0.39%)
49
(0.40%)
43
(0.35%)
111
(0.90%)
12,040
(97.96%)
c424aYou discovered you were
adopted.
12,291251
(2.04%)
12,040
(97.96%)
c425Your family moved to a new
district.
12,291461
(3.75%)
667
(5.43%)
900
(7.32%)
1,288
(10.48%)
8,975
(73.02%)
c425aYour family moved to a new
district.
12,2913,316
(26.98%)
8,975
(73.02%)
c426You were in trouble with the
police.
12,29161
(0.50%)
83
(0.68%)
172
(1.40%)
177
(1.44%)
11,798
(95.99%)
c426aYou were in trouble with the
police.
12,291493
(4.01%)
11,798
(95.99%)
c427You were expelled or suspended
from school.
12,29138
(0.31%)
55
(0.45%)
134
(1.09%)
226
(1.84%)
11,838
(96.31%)
c427aYou were expelled or suspended
from school.
12,291453
(3.69%)
11,838
(96.31%)
c428You failed an important exam.12,291159
(1.29%)
338
(2.75%)
562
(4.57%)
451
(3.67%)
10,781
(87.71%)
c428aYou failed an important exam.12,2911,510
(12.29%)
10,781
(87.71%)
c429Your family’s financial
circumstances got worse.
12,291172
(1.40%)
330
(2.68%)
565
(4.60%)
479
(3.90%)
10,745
(87.42%)
c429aYour family’s financial
circumstances got worse.
12,2911,546
(12.58%)
10,745
(87.42%)
c430You acquired a stepbrother or
stepsister.
12,291128
(1.04%)
133
(1.08%)
232
(1.89%)
456
(3.71%)
11,342
(92.28%)
c430aYou acquired a stepbrother or
stepsister.
12,291949
(7.72%)
11,342
(92.28%)
c431Other important happening.12,291224
(1.82%)
59
(0.48%)
22
(0.18%)
9
(0.07%)
11,977
(97.45%)
c431aOther important happening.12,293313
(2.57%)
11,880
(97.43%)
Table 2b.
Partner’s Life Events Scale indicating the potentially traumatic events that had occurred to the mother’ before 17 years of age, using questions based on Coddington 4 with the mother’s partner’s indication as to what effect they had had on him.
Variable
Number
QuestionCategorical ResponsesBinary responses
NAffected
a lot
Affected
a bit
Mild
effect
No effectDid not
happen
YesNo
Please indicate if any of the
following events happened to you
before you were 17 and how much
it affected you.
pb450A parent died9,957409
(4.11%)
101
(1.01%)
42
(0.42%)
55
(0.55%)
9,350
(93.90%)
pb450aA parent died9,957607
(6.10%)
9,350
(93.90%)
pb451A brother or sister died9,957112
(1.12%)
46
(0.46%)
51
(0.51%)
134
(1.35%)
9,614
(96.56%)
pb451aA brother or sister died9,957343
(3.44%)
9,614
(96.56%)
pb452A relative died9,957693
(6.96%)
1,038
(10.42%)
2,204
(22.14%)
2,171
(21.80%)
3,851
(38.68%)
pb452aA relative died9,9576,106
(61.32%)
3,851
(38.68%)
pb453A friend died9,957273
(2.74%)
508
(5.10%)
790
(7.93%)
567
(5.69%)
7,819
(78.53%)
pb453aA friend died9,9572,138
(21.47%)
7,819
(78.53%)
pb454A parent had a serious illness9,957739
(7.42%)
614
(6.17%0
556
(5.58%)
374
(3.76%)
7,674
(77.07%)
pb454aA parent had a serious illness9,9572,283
(22.93%)
7,674
(77.07%)
pb455A parent was in hospital9,957748
(7.51%)
808
(8.11%)
1,218
(12.23%)
1,332
(13.38%)
5,851
(58.76%)
pb455aA parent was in hospital9,9574,106
(41.24%)
5,851
(58.76%)
pb456You had a serious physical illness9,957333
(3.34%)
194
(1.95%)
277
(2.78%)
249
(2.50%)
8,904
(89.42%)
pb456aYou had a serious physical illness9,9571,053
(10.58%)
8,904
(89.42%)
pb457You were in hospital9,957409
(4.11%)
475
(4.77%)
938
(9.42%)
2,131
(21.40%)
6,004
(60.30%)
pb457aYou were in hospital9,9573,953
(39.70%)
6,004
(60.30%)
pb458Brother or sister had a serious
illness
9,957174
(1.75%)
197
(1.98%)
321
(3.22%)
371
(3.73%)
8,894
(89.32%)
pb458aBrother or sister had a serious
illness
9,9571,063
(10.68%)
8,894
(89.32%)
pb459Brother or sister was in hospital9,957213
(2.14%)
269
(2.70%)
568
(5.70%)
1,343
(13.49%)
7,564
(75.97%)
Pb459aBrother or sister was in hospital9,9572,393
(24.03%)
7,564
(75.97%)
pb460A parent had a serious accident9,957143
(1.44%)
138
(1.39%)
183
(1.84%)
172
(1.73%)
9,321
(93.61%)
pb460aA parent had a serious accident9,957636
(6.39%)
9,321
(93.61%)
pb461You had a serious accident9,957209
(2.09%)
183
(1.84%)
240
(2.41%)
304
(3.05%)
9,022
(90.61%)
pb461aYou had a serious accident9,957935
(9.39%)
9,022
(90.61%)
pb462Brother or sister had a serious
accident
9,957116
(1.17%)
140
(1.41%)
216
(2.17%)
217
(2.18%)
9,268
(93.08%)
pb462aBrother or sister had a serious
accident
9,957689
(6.92%)
9,268
(93.08%)
pb463You acquired a physical deformity9,95741
(0.41%)
36
(0.36%)
39
(0.39%)
39
(0.39%)
9,802
(98.44%)
pb463aYou acquired a physical deformity9,957155
(1.56%)
9,802
(98.44%)
pb464Your girlfriend became pregnant9,957152
(1.53%)
53
(0.53%)
57
(0.57%)
67
(0.67%)
9,628
(96.70%)
pb464aYour girlfriend became pregnant9,957329
(3.30%)
9,628
(96.70%)
pb465A parent was imprisoned9,95738
(0.38%)
16
(0.16%)
23
(0.23%)
60
(0.60%)
9,820
(98.62%)
pb465aA parent was imprisoned9,957137
(1.38%)
9,820
(98.62%)
pb466A parent was physically cruel to
you
9,957171
(1.72%)
93
(0.93%)
128
(1.29%)
99
(0.99%)
9,466
(95.07%)
pb466aA parent was physically cruel to
you
9,957491
(4.93%)
9,466
(95.07%)
pb467Your parents separated9,957641
(6.44%)
339
(3.40%)
313
(3.14%)
261
(2.62%)
8,403
(84.39%)
pb467aYour parents separated9,9571,554
(15.61%)
8,403
(84.39%)
pb468Your parents divorced9,957461
(4.63%)
268
(2.69%)
256
(2.57%)
277
(2.78%)
8,695
(87.33%)
pb468aYour parents divorced9,9571,262
(12.67%)
8,695
(87.33%)
pb469A parent remarried9,957245
(2.46%)
183
(1.84%)
226
(2.27%)
336
(3.37%)
8,967
(90.06%)
pb469aA parent remarried9,957990
(9.94%)
8,967
(90.06%)
pb470A parent was emotionally cruel
to you
9,957247
(2.48%)
153
(1.54%)
212
(2.13%)
87
(0.87%)
9,258
(92.98%)
pb470aA parent was emotionally cruel
to you
9,957699
(7.02%)
9,258
(92.98%)
pb471Your parents had serious
arguments
9,957665
(6.68%)
664
(6.67%)
942
(9.46%)
815
(8.19%)
6,871
(69.01%)
pb471aYour parents had serious
arguments
9,9573,086
(30.99%)
6,871
(69.01%)
pb472You were sexually abused9,95753
(0.53%)
24
(0.24%)
23
(0.23%)
23
(0.23%)
9,834
(98.76%)
pb472aYou were sexually abused9,957123
(1.24%)
9,834
(98.76%)
pb473A parent was mentally ill9,957123
(1.24%)
85
(0.85%)
67
(0.67%)
76
(0.76%)
9,606
(96.47%)
pb473aA parent was mentally ill9,957351
(3.53%)
9,606
(96.47%)
pb474You discovered you were adopted9,95743
(0.43%)
29
(0.29%)
38
(0.38%)
92
(0.92%)
9,755
(97.97%)
pb474aYou discovered you were adopted9,957202
(2.03%)
9,755
(97.97%)
pb475Your family moved to a new district9,957395
(3.97%)
501
(5.03%)
853
(8.57%)
1,423
(14.29%)
6,785
(68.14%)
pb475aYour family moved to a new district9,9573,172
(31.86%)
6,785
(68.14%)
pb476You were in trouble with the police9,957263
(2.64%)
245
(2.46%)
524
(5.26%)
926
(9.30%)
7,999
(80.34%)
pb476aYou were in trouble with the police9,9571,958
(19.66%)
7,999
(80.34%)
pb477You were expelled or suspended
from school
9,95793
(0.93%)
82
(0.82%0
220
(2.21%)
610
(6.13%0
8,952
(89.91%)
pb477aYou were expelled or suspended
from school
9,9571,005
(10.09%)
8,952
(89.91%)
pb478You failed an important exam9,957210
(2.11%)
316
(3.17%)
646
(6.49%)
978
(9.82%)
7,807
(78.41%)
pb478aYou failed an important exam9,9572,150
(21.59%)
7,807
(78.41%)
pb479Your family’s financial
circumstances got worse
9,957188
(1.89%)
272
(2.73%)
447
(4.49%)
606
(6.09%)
8,444
(87.80%)
pb479aYour family’s financial
circumstances got worse
9,9571,513
(15.20%)
8,444
(84.80%)
pb480Another important happening
(please tick and describe)
9,957186
(1.87%)
46
(0.46%)
31
(0.31%)
16
(0.16%)
9,678
(97.20%)
pb480aAnother important happening
(please tick and describe)
9,957279
(2.80%)
9,678
(97.20%)

From the life events scale, two variables were created. The first, the weighted life events scores (c432 and pb481) gives an indication of the perceived degree of effect of each life event the parent experienced. Thus, c432 was created by selecting variables c400-c430, reversing the coding for these variables and setting ‘no’ to 0 (unless all were missing in which case the variable was left as missing). Therefore, greater perceived effects will have a higher score; addition of all life events variables together provides the overall score. [Variable c431 was not included in the score as analysis showed that when another event was noted, it closely matched another variable between c400-c430 and had been coded into that variable]. The same coding system was used for the partners’ variables, pb450 to pb479 ( Figure 1a, Figure1b). The range for mothers and partners were 0-107 and 0-78, with medians of 6 and 7 respectively.

a. Mother’s Weighted Life Events Score.
b. Partner’s Weighted Life Events Score.
Figure 1.
a. Mother’s Weighted Life Events Score. b. Partner’s Weighted Life Events Score.

The second derived variables, the Life Events Scores (c433 and pb482), gives the number of life events experienced by each parent and was created by recoding the variables to make all ‘yes’ responses as 1 and the ‘no’ responses as 0, and then adding these variables together. For the mother’s data, the variables used to create the score were c400-c430. The variables used to create the partners’ score were pb450 to pb479. The ranges were 0-27 and 0-22 and medians 3 and 3.5 for mothers and partners respectively ( Figures 2a, 2b).

a. Mother’s Life Events Score.
b. Partner’s Life Events Score.
Figure 2.
a. Mother’s Life Events Score. b. Partner’s Life Events Score.

Other childhood circumstances

Questions relating to other circumstances during the parents’ childhood can be found in Table 3a and Table 3b. Variables indicating further questions where the respondent was asked to indicate their actual age at which circumstances occurred are shown in Table 4a and Table 4b. Although not listed in this table, ages are also available for when specific accidents and injuries had occurred, thus enabling childhood events to be computed (see variables d080 to d130 for the mothers and pa110 to pa163 for their partners).

Table 3a.
Mother’s childhood circumstances that might indicate stress during childhood as self-reported in the D questionnaire.
Variable NumberQuestionCategorical responsesBinary responses
NYesNoUnsure
d380 *Were you legally adopted?12,293354
(2.88%)
11,939
(97.12%)
d385Were you ever “in care” of either a
local authority or voluntary agency
e.g. Barnardo’s?
11,911264
(2.22%)
11,564
(97.09%)
83
(0.70%)
d387Did your parents’ divorce or
separate before your 18 th birthday?
12,2352,372
(19.39%)
9,863
(80.61%)
NMotherFatherSome-times Mum, Some-times DadSomeone else
d389Who did you mainly live with after parents
divorced or separated?
2,3281,757
(75.47%)
315
(13.53%)
88
(3.78%)
168
(7.22%)
YesNo
Did you ever live away from home
with any of the following (other than
holidays or short visits) before
you were 18 years old?
NYesNoDon’t Know
d392Grandparents12,294654
(5.32%)
11,640
(94.68%)
d393Other relatives12,294493
(4.01%)
11,801
(95.99%)
d394Friends12,294469
(3.81%)
11,825
(96.19%)
d395Foster parents12,294161
(1.31%)
12,132
(98.68%)
<5
(0.01%)
d396Other home12,294641
(5.21%)
11,653
(94.79%)
NYes <1 weekYes 1 week to 1monthYes 1 to 6 monthsYes >6 monthsYes, Not known how longNoYesNo
Did you ever stay away from home
in any of the following places before
you were 18 years old?
d400Hospital12,2503,085
(25.18%)
1,654
(13.50%)
203
(1.66%)
34
(0.28%)
7,274
(59.38%)
d400aHospital12,2504,976
(40.62%)
7,274
(59.38%)
d401Boarding school12,19815
(0.12%)
24
(0.20%)
65
(0.53%)
359
(2.94%)
11,735
(96.20%)
d401aBoarding school12,198463
(3.80%)
11,735
(96.20%)
d402Children’s home12,1906
(0.05%)
21
(0.17%)
45
(0.37%)
121
(0.99%)
11,997
(98.42%)
d402aChildren’s home12,190193
(1.58%)
11,997
(98.42%)
d403Hostel12,14874
(0.61%)
69
(0.57%)
20
(0.16%)
37
(0.30%)
11,948
(98.35%)
d403aHostel12,148200
(1.65%)
11,948
(98.35%)
d404Stayed in custody12,136<5
(0.03%)
7
(0.06%)
10
(0.08%)
<5
(0.03%)
12,111
(99.79%)
d404aStayed in custody12,13625
(0.21%)
12,111
(99.79%)
d405Stayed in another place12,36084
(0.68%)
275
(2.22%)
111
(0.90%)
211
(1.71%)
16
(0.13%)
11,663
(94.36%)
d405sStayed in another place12,360697
(5.64%)
11,663
(94.36%)
d410Did you leave home before your
18 th birthday?
12,2992,451
(19.93%)
9,848
(80.07%)
NCollege accommodationHostelBedsitShared accommodationOtherYesNo
d411Where Mother lived when she first
left home before 18 years
2,336232
(9.93%)
47
(2.01%)
413
(17.68%)
864
(36.99%)
780
(33.39%)
Before you were 17 did a parent or
person who cared for you die?
YesNo
d620Mother12,448218
(1.75%)
12,230
(98.25%)
d621Father12,448491
(3.94%)
11,957
(96.06%)
d622Mother figure12,44833
(0.27%)
12,415
(99.73%)
d623Father figure12,44837
(0.30%)
12,411
(99.70%)
d624Other (please describe)12,448591
(4.75%)
11,857
(95.25%)
d625Carer died before Mum was 1712,4481,289
(10.36%)
11,159
(89.64%)
NAlwaysMostlyRarelyNever
Was your parent’s behaviour stable
and predictable to you as a child?
d750Mother12,0276,833
(56.81%)
4,543
(37.77%)
470
(3.91%)
181
(1.50%)
d751Father11,4656,281
(54.78%)
4,168
(36.35%)
711
(6.20%)
305
(2.66%)
d752Mother figure436202
(46.33%)
157
(36.01%)
38
(8.72%)
39
(8.94%)
d753Father figure697288
(41.32%)
274
(39.31%)
73
(10.47%)
62
(8.90%)
NVery stableFairly stableUnstableVery unstable
d755Stability of home in childhood12,2305,561
(45.47%)
5,139
(42.02%)
1,054
(8.62%)
476
(3.89%)
* d380 spans ages beyond 17 so only cases where the event happened before 18 years of age have been coded at “yes”. The full age ranges available can be found in Table 4a
Table 3b.
Partner’s childhood circumstances that might indicate stress during childhood as self-reported in the PA questionnaire
Variable
Number
QuestionCategorical responsesBinary responses
NYesNoUnsureYesNo
pa380*Were you legally adopted?8,405199
(2.37%)
8,206
(97.63%)
pa385Were you ever in care of either
a local authority or voluntary agency
Barnardo’s?
8,162176
(2.16%)
7,926
(97.11%)
60
(0.74%)
pa387Did your parents’ divorce or
separate before your 18 th birthday?
8,3301,312
(15.75%)
7,018
(84.25%)
NMotherFatherShared
Mother
and Father
Someone elseYesNo
pa389Who did you live with after parents
divorced?
8,317891
(69.12%)
214
(16.60%)
59
(4.58%)
125
(9.70%)
Did you ever live away from home
with any of the following (other than
for holidays/ or short visits) before
you were 18 years old?
pa392Grandparents8,345481
(5.76%)
7,864
(94.24%)
pa393Other relatives8,345342
(4.10%)
8,003
(95.90%)
pa394Friends8,345303
(3.63%)
8,042
(96.37%)
pa395Foster parents8,34571
(0.85%)
8,274
(99.15%)
pa396Other8,345517
(6.20%)
7,828
(93.80%)
NYes, <1 weekYes, 1
week to
1 month
Yes, 1 to 6
months
Yes, > 6 monthsYes,
duration
not known
No, did not
happen
YesNo
Did you ever stay away from home
in any of the following places before
you were 18 years old?
pa400Hospital8,2682,106
(25.47%)
1,399
(16.92%)
273
(3.30%)
66
(0.80%)
4,424
(53.51%)
pa400aHospital8,2683,844
(46.49%)
4,424
(46.49%)
pa401Boarding school8,2385
(0.06%)
23
(0.28%)
65
(0.79%)
436
(5.29%)
7,709
(93.58%)
pa401aBoarding school8,238529
(6.42%)
7,709
(93.58%)
pa402Children’s home8,212<5
(0.02%)
21
(0.26%)
19
(0.23%)
90
(1.10%)
8,080
(98.39%)
pa402aChildren’s home8,212132
(1.61%)
8,080
(98.39%)
pa403Hostel8,18696
(1.17%)
122
(1.49%)
11
(0.13%)
30
(0.37%)
7,927
(96.84%)
pa403aHostel8,186259
(3.16%)
7,927
(96.84%)
pa404Stayed in custody8,18545
(0.55%)
31
(0.38%)
58
(0.71%)
67
(0.82%)
7984
(97.54%)
pa404aStayed in custody8,185201
(2.46%)
7,984
(97.54%)
pa405Other8,41065
(0.77%)
263
(3.13%)
82
(0.98%)
244
(2.90%)
41
(0.49%)
7,715
(91.74%)
pa405aOther8,410695
(8.26%)
7,715
(91.74%)
pa410Did you leave home before your
18 th birthday?
8,3001,561
(18.81%)
6,739
(81.19%)
NCollege AccommodationHostelBedsitShared AccommodationOther
pa411Where partner lived when they left
home <18 years
1,498261
(17.42%)
37
(2.47%)
233
(15.55%)
405
(27.04%)
562
(37.52%)
Yes, bothYes, motherYes, fatherNo, neitherYesNo
Before you were 17 did a parent or
person who cared for you die?
pa619Either parent died1,191<5
(0.08%)
16
(1.34%)
58
(4.87%)
1,116
(93.70%)
pa620Mother8,621116
(1.35%)
8,505
(98.65%)
pa621Father8,621283
(3.28%)
8,338
(96.72%)
pa622Mother figure8,62111
(0.13%)
8,610
(99.87%)
pa623Father figure8,62124
(0.28%)
8,597
(99.72%)
pa624Other8,621390
(4.52%)
8,231
(95.48%)
pa625One of above
carers died
8,621789
(9.15%)
7,832
(90.85%)
Yes,
hospitalised
Yes, saw
a doctor
Yes, home
treatment
No, neverYesNo
Have any of the following ever happened?
pa131*You were sexually
assaulted
8,371N/A13
(0.16%)
66
(0.79%)
8,292
(99.06%)
pa132*You were sexually
assaulted
8,37179
(0.69%)
8,313
(99.31%)
NAlwaysMostlyRarelyNever
Was your parent’s behaviour stable
and predictable as a child?
pa750Mother8,1614,715
(57.77%)
3,113
(38.14%)
232
(2.84%)
101
(1.24%)
pa751Father7,8094,288
(54.91%)
2,953
(37.82%)
399
(5.11%)
169
(2.16%)
pa752Mother figure303147
(48.51%)
118
(38.94%)
17
(5.61%)
21
(6.93%)
pa753Father figure453209
(46.14%)
173
(38.19%)
38
(8.39%)
33
(7.28%)
NVery stableFairly stableUnstableVery unstable
pa755Home stability in childhood8,2963,892
(46.91%)
3,607
(43.48%)
563
(6.79%)
234
(2.82%)
* pa131, pa132and pa380 span ages beyond 17 so cases where the event happened after 18 years of age have been coded as “no”. The full age ranges available for these events can be found in Table 4b in variables pa133 and pa381
Table 4a.
Questions asked concerning the mother’s notable events together with for her age at which the event occurred, thus enabling the women who had experienced the event at particular stages of childhood to be identified.
Variable NumberQuestionNRange
b023Age when pregnant for the very first time?13,17910 – 44
d103Age Mother was sexually assaulted4182 – 34
d381Age Mother was adopted3180 – 27
d388Age when her parents divorced or
separated before 18 th birthday
2,2110 – 17
d630Age when her mother died4080 – 17+
d631Age her father died7890 – 17+
d632Age when her Mother figure died550 – 17+
d633Age when Father figure died590 – 17+
d634Age when another carer died5760 – 17+
h136dAge when first physically abused4580 – 16
Table 4b.
Questions asked concerning the notable events occurring to the mother’s partner during childhood, together with his age at which the event occurred, thus enabling the partner who had experienced the event at particular stages of childhood to be identified.
Variable numberQuestionNRange
pa133Age when he was sexually assaulted711–33
pa381Age he was legally adopted2070–40
pa388Age when his parents divorced or separated1,2130–18+
pa630Age when his mother died3390–17+
pa631Age when his father died6750–17+
pa632Age when his mother figure died710–17+
pa633Age when his father figure died880–17+
pa634Age when another carer died3990–17+

Subsequent to pregnancy, at 33 months after delivery, further questions were asked about abuse during childhood as well as of violent events in the home. The reason for the delay in asking these questions concerned the realisation that they should have been asked earlier but would still be valid to ask at this stage in the parents’ life course ( Table 5a and Table 5b).

Table 5a.
Mothers recall of childhood abuse and domestic violence asked at 33 months postpartum.
Variable NumberQuestionCategorical responsesBinary responses
NYes, SeverelyYes, somewhatNo, not at all
h134Did you feel emotionally neglected
during your childhood?
9,574251
(2.62%)
1,844
(19.26%)
7,479
(78.12%)
h135Were you physically neglected
as a child (e.g.
not fed or clothed properly)?
9,58525
(0.26%)
165
(1.72%)
9,395
(98.02%)
h136Were you physically abused (e.g. beaten) as a child?9,55371
(0.74%)
525
(5.50%)
8,957
(93.76%)
Who abused you?YesNo
h136aMother 9,361248
(2.65%)
9,113
(97.35%)
h136bFather9,393326
(3.47%)
9,067
(96.53%)
h136cAnother person9,133176
(1.93%)
8,957
(98.07%)
NYes, alwaysYes, frequentlyYes, some-whatNo, Not at all
How would you describe the
relationship between your mother
and father when you were growing up?
h137aViolent8,81959
(0.67%)
185
(2.10%)
949
(10.76%)
7,626
(86.47%)
h137bAffectionate8,9341,367
(15.30%)
2,273
(25.44%)
4,178
(46.77%)
1,116
(12.49%)
h137cQuarrelsome8,993330
(3.67%)
1,524
(16.95%)
5,139
(57.11%)
2,003
(22.27%)
h137dHappy9,0022,107
(23.41%)
3,716
(41.28%)
2,718
(30.19%)
461
(5.12%)
h137eFrightening8,88077
(0.87%)
274
(3.09%)
1,355
(15.26%)
7,174
(80.79%)
h137fFriendly8,9383,293
(36.84%)
3,163
(35.39%)
2,151
(24.07%)
331
(3.70%)
h137gRespectful8,9053,260
(36.61%)
2,617
(29.39%)
2,236
(25.11%)
792
(8.89%)
h137hRemote8,863246
(2.78%)
696
(7.85%)
2,797
(31.56%)
5,124
(57.81%)
Table 5b.
Mothers’ partners’ recall of childhood abuse and domestic violence asked at 33 months postpartum.
Variable
Number
QuestionCategorical ResponsesBinary responses
NYes,
Severely
Neglected
Yes,
Somewhat
Neglected
No, not at
all
pf2060Did you feel neglected
emotionally during your
childhood?
5,412106
(1.96%)
976
(18.03%)
4,330
(80.01%)
pf2061Were you physically neglected
as a child (e.g. not fed or
clothed properly)?
5,42522
(0.41%)
117
(2.16%)
5,286
(97.44%)
NYes,
Severely
Abused
Yes,
Somewhat
Abused
No, not at
all
YesNo
pf2062Were you physically abused
(e.g. beaten) as a child?
5,42240
(0.74%)
274
(5.05%)
5,108
(94.21%)
Who abused you?
pf2063Mother290104
(35.86%)
186
(64.14%)
pf2064Father328220
(67.07%)
108
(32.93%)
pf2065Someone else7979
( *%)
- *
NYes,
always
Yes,
frequently
Yes,
Sometimes
No, Not
at all
Single
parent
family
How would you describe the
relationship between your
mother and father when you
were growing up?
pf2070Violent4,77114
(0.29%)
100
(2.10%)
475
(9.96%)
4,182
(87.65%)
pf2071Affectionate4,921630
(12.80%)
1,295
(26.32%)
2,414
(49.06%)
457
(9.29%)
125
(2.54%)
pf2072Quarrelsome4,83193
(1.93%)
681
(14.10%)
2,826
(58.50%)
1,231
(25.48%)
pf2073Happy4,8521,030
(21.23%)
2,212
(45.59%)
1,435
(29.58%)
175
(3.61%)
pf2074Frightening4,78727
(0.56%)
101
(2.11%)
673
(14.06%)
3,986
(83.27%)
pf2075Friendly4,8211,751
(36.32%)
1,794
(37.21%)
1,137
(23.58%)
139
(2.88%)
pf2076Respectful of one another5,2032,207
(42.42%)
1,629
(31.31%)
1,133
(21.78%)
234
(4.50%)
pf2077Remote or distant from one another5,109110
(2.15%)
425
(8.32%)
1,739
(34.04%)
2,835
(55.49%)
* For question pf2065, no was coded as missing and therefore we do not have a figure for the number of people

Childhood happiness and unhappiness

Each parent was asked to rate their memories of happiness/unhappiness at each of three ages: under 6, 6-11 and 12-15 years. As a validation exercise, the mother was asked to do this on two separate occasions, and the data are found in the C files and the D files. Table 6a shows these data, and Table 6b lists the partners’ memories of happiness in their own childhoods as self-reported on one occasion during pregnancy.

Table 6a.
Mother’s memories of happiness and unhappiness in childhood:
Variable NumberQuestionNVery happyModerately happyNot really happyQuite unhappyVery unhappyCan’t remember
Looking back would you call
your childhood happy?
c4410–5 years12,3057,984
(64.88%)
2,068
(16.81%)
175
(1.42%)
47
(0.38%)
55
(0.45%)
1,976
(16.06%)
c4426–11 years12,2917,355
(59.84%)
3,686
(29.99%)
619
(5.04%)
204
(1.66%)
194
(1.58%)
233
(1.89%)
c44312–15 years12,2935,231
(42.55%)
4,796
(39.01%)
1,251
(10.18%)
474
(3.86%)
484
(3.94%)
57
(0.46%)
d7600–5 years12,4888,849
(71.09%)
1,605
(12.89%)
206
(1.65%)
46
(0.37%)
53
(0.43%)
1,689 *
(13.57%)
d7616–11 years12,4487,886
(63.35%)
3,224
(25.90%)
668
(5.37%)
194
(1.56%)
185
(1.49%)
291 *
(2.34%)
d76212–15 years12,4485,436
(43.67%)
4,529
(36.38%)
1,329
(10.68%)
467
(3.75%)
508
(4.08%)
179 *
(1.44%)
* For the C questionnaire, ‘Can’t Remember’ was coded as a separate category to those who had responded to the questionnaire but had not answered this particular question. Those who had not answered the question were coded as missing data. For the D questionnaire, instances of ‘Can’t Remember’ have been coded as missing data alongside those who did not answer the question. Therefore, for the D questionnaire, we cannot be certain that every response for ‘Can’t Remember’ is a genuine response and not a missing case.
Table 6b.
Mother’s partner’s memories of happiness and unhappiness in childhood.
Variable
Number
QuestionNVery
Happy
Moderately
Happy
Not Really
Happy
Quite
happy
Very
Unhappy
Looking back would you
call your childhood happy?
pa7600–5 years7,1835,634
(78.44%)
1,381
(19.23%)
111
(1.55%)
20
(0.28%)
37
(0.52%)
pa7616–11 years8,2185,148
(62.64%)
2,515
(30.60%)
367
(4.47%)
101
(1.23%)
87
(1.06%)
pa76212–15 years8,3094,061
(48.87%)
3,119
(37.54%)
724
(8.71%)
237
(2.85%)
168
(2.02%)
pa763*Overall childhood
happiness
8,3293,685
(44.24%)
3,272
(39.28%)
881
(10.58%)
271
(3.25%)
220
(2.64%)
The pa763 Overall childhood happiness score is a derived variable computed by adding together the three variables (pa760–pa762) in section F Question 18 of the PA Partners Questionnaire. These questions asked the partner to rate their childhood happiness at 0–5 years (pa760), 6–11 years (pa761) and 12–15 years (pa762)

Maternal care score

The Parental Bonding Instrument 28 is a scale that seeks to define the principal dimensions of child/parent bonding and to examine the importance of these factors in determining the strength of a child’s relationship with their parent. In 1987, Gamsa 29 re-wrote several of the questions in the Parental Bonding Instrument as in the original test, five of the questions contained double negatives which were considered to be confusing to participants.

The ALSPAC team also changed the responses for the questions as piloting revealed that the participants did not like the original options given in the test. Participants were asked to look at statements and rate how like their relationship with their mother the statements were. The answers in the original scale are “Very like”, “Moderately like”, “Moderately unlike” and “Very unlike”. These answers were changed to “Never”, “Sometimes” and “Usually”. In addition, three questions were removed from the test due to their similarity and the perceived repetition causing annoyance to the participants. The responses to each question used are shown in Table 7a and Table 7b for each parent.

Table 7a.
All variables relate to the period up until the mother was 16 years of age.
Variables that make up the Gamsa 29 (1987) adapted version of the Parental Bonding Instrument (Parker, Tupling and Brown (1979) 28).
Variable
Number
QuestionNNeverSometimesUsuallyDon’t
Know
YesNo
d700My mother spoke to me with a warm and
friendly voice
12,173202
(1.66%)
2,368
(19.45%)
9,603
(78.89%)
d701My mother helped me as much as I needed12,210325
(2.66%)
2,087
(17.09%)
9,798
(80.25%)
d702My mother let me do those things I liked
doing
12,236228
(1.86%)
4,930
(40.29%)
7,078
(57.85%)
d703My mother seemed emotionally cold to me12,1859,294
(76.27%)
2,296
(18,84%)
595
(4.88%)
d704My mother appeared to understand my
problems and worries
12,211978
(8.00%)
5,074
(41.53%)
6,165
(50.46%)
<5
(0.01%)
d705My mother was affectionate to me12,212558
(4.57%)
3,097
(25.36%)
8,557
(70.07%)
d706My mother tried to control what I did12,2051,614
(13.22%)
7,494
(61.40%)
3,097
(25.37%)
d707My mother invaded my privacy12,1896,418
(52.65%)
4,780
(39.22%)
991
(8.13%)
d708My mother let me decide things for myself12,217563
(4.61%)
6,122
(50.11%)
5,532
(45.28%)
d709My mother made me feel I wasn’t wanted12,21910,200
(83.48%)
1,541
(12.61%)
478
(3.91%)
d710My mother talked things over with me12,2231,216
(9.95%)
5,584
(45.68%)
5,423
(44.37%)
d711My mother gave me the freedom I wanted12,213899
(7.36%)
6,940
(56.82%)
4,373
(35.81%)
<5
(0.01%)
d712My mother praised me12,792832
(6.82%)
5,012
(41.11%)
6,348
(52.07%)
YesNo
d713My mother enjoyed talking things over with
me
11,9989,648
(80.41%)
2,350
(19.59%)
d714My mother frequently smiled at me12,10410,828
(89.46%)
1,276
(10.54%)
d715My mother tended to baby me12,1412,360
(19.44%)
9,781
(80.56%)
d716My mother seemed to understand what I
needed or wanted
11,9819,323
(77.81%)
2,658
(22.19%)
d717My mother could make me feel better when I
was upset
12,04410,390
(86.27%)
1,654
(13.73%)
d718My mother felt I could not look after myself
unless she was around.
12,0971,890
(15.62%)
10,207
84.38%)
d719My mother let me go out as often as I
wanted
12,0045,484
(45.68%)
6,520
(54.32%)
d720My mother was overprotective of me12,0622,537
(21.03%)
9,525
(78.97%)
d721My mother let me dress in any way I pleased12,0416,935
(57.59%)
5,106
(42.41%)
Table 7b.
All variables relate to the period up until the mother’s partner was 16 years of age.
Variables that make up the Gamsa 29 (1987) adapted version of the Parental Bonding Instrument (Parker, Tupling and Brown (1979) 28).
Variable
Number
QuestionNNeverSometimesUsuallyDon’t
Know
YesNo
pa700My mother spoke to me with a warm and
friendly voice
7,057105
(1.49%)
1,387
(19.65%)
5,565
(78.86%)
pa701My mother helped me as much as I needed7,075149
(2.11%)
1,208
(17.07%)
5,718
(80.82%)
pa702My mother let me do those things I liked doing7,11268
(0.96%)
2,879
(40.48%)
4,165
(58.56%)
pa703My mother seemed emotionally cold to me7,0865,777
(81.53%)
1,049
(14.80%)
260
(3.67%)
pa704My mother appeared to understand my
problems and worries
7,092451
(6.36%)
2,994
(42.22%)
3,647
(51.42%)
pa705My mother was affectionate to me7,104226
(3.18%)
1,828
(25.73%)
5,050
(71.09%)
pa706My mother tried to control what I did7,096847
(11.94%)
4,219
(59.46%)
2,030
(28.61%)
pa707My mother invaded my privacy7,0953,825
(53.91%)
2,798
(39.44%)
472
(6.65%)
pa708My mother let me decide things for myself7,098223
(3.14%)
3,395
(47.83%)
3,480
(49.03%)
pa709My mother made me feel I wasn’t wanted7,0986,240
(87.91%)
654
(9.21%)
204
(2.87%)
pa710My mother talked things over with me7,091774
(10.92%)
3,909
(55.13%)
2,408
(33.96%)
pa711My mother gave me the freedom I wanted7,091265
(3.74%)
3,484
(49.13%)
3,342
(47.13%)
pa712My mother praised me7,090368
(5.19%)
3,325
(46.90%)
3,397
(47.91%)
YesNo
pa713My mother enjoyed talking things over with me6,9845,483
(78.51%)
1,501
(21.49%)
pa714My mother frequently smiled at me7,0576,411
(90.85%)
646
(9.15%)
pa715My mother tended to baby me7,0362,056
(29.22%)
4,980
(70.78%)
pa716My mother seemed to understand what I needed or wanted7,0135,682
(81.02%)
1,331
(18.98%)
pa717My mother could make me feel better when I was upset7,0226,143
(87.48%)
879
(12.52%)
pa718My mother felt I could not look after myself unless she was around.7,0391,315
(18.68%)
5,724
(81.32%)
pa719My mother let me go out as often as I wanted7,0274,093
(58.25%)
2,934
(41.75%)
pa720My mother was overprotective of me7,0321,463
(20.80%)
5,569
(79.20%)
pa721My mother let me dress in any way I pleased7,0214,198
(59.79%)
2,823
(40.21%)

From the questions two separate scales were derived as specified by Gamsa indicating (a) maternal care and (b) maternal over-protection. These can be found in Table 8. To create these variables, all coding was reversed for variables d702, d703, d708, d709 and d711 to make the negative response have the higher value. The binary variables d713, d714, d715, d716, d717, d718, d719, d720 and d721 were also recoded so that they faced the same direction.

Table 8.
Derived continuous variables based on questions asked of each parent about their relationship with their mother during childhood.
Variable NumberQuestionNRange
Study mother
d724Maternal care score using the Parental Bonding Instrument11,4310 – 24
d725Maternal care score: Modes/no. missing cases *12,4470 – 24
d726Maternal care score: No. missing items12,4480 – 12
d727Maternal over protection score using the Parental Bonding Instrument11,5450 – 20
d728Maternal over protection score: Modes/no. missing cases *12,4470 – 20
d729Maternal over protection score: No. missing items12,4470 – 10
Study father
pa724Maternal care score6,7070–24
pa725Maternal care score – Modes/missing cases *7,1170–24
pa726Maternal care score –No. missing items7,3050–12
pa727Maternal over protection score6,8190–20
pa728Maternal over protection score – Modes/ missing cases *7,1080–20
pa729Maternal over protection score – No. missing cases7,3050–10
* Missing cases were put to the modes of the distribution

The Maternal Care Score, d724 ( Figure 3a) was created by adding together the responses for variables d700, d701, d703, d704, d705, d709, d710, d712, d713, d714, d716 and d717, then minus 12 from the total. The over protection scale d727 ( Figure 3b) was created by adding together the responses for variables d702, d706, d707, d708, d707, d711, d717, d718, d719, d720 and d721, and then minus 10 from the total. Similar coding and creating of derived variables were undertaken for the paternal scales.

a. Maternal Care Score.
b. Maternal Overprotection Score.
Figure 3.
a. Maternal Care Score. b. Maternal Overprotection Score.

The Maternal Care Score variable comprises a continuous measure of how much the study parent thought their own mother cared for them on a scale of 0–24, with 24 being the most caring mothers. The Overprotection Scale measured how overprotective the study parent thought their own mother was on a scale of 0–20, with 20 being the most overprotective mothers. The numbers of cases in each scale are shown firstly for the scales based on complete data, secondly for scales where the missing response to the individual data have been replaced by the mode for the item, and thirdly the number of such missing items are given.

Strengths and limitations of the data

The strengths of these data include the large sample size, with over 20,000 participants with data available 23. The only inclusion requirements at enrolment for this study were the geographical location the participating mother resided in and the expected date of delivery. The participants recruited to the study were broadly representative of the general population of new parents' resident in the area at the time in terms of sex, ethnicity and socio-economic status 24.

All parent participants received the same questions and one of the major strengths of this study is the vast array of other data that is available with several decades of follow up and the opportunity to examine effects across generations. Available data includes information about the study parents’ relationships with the study child, biological markers from parents and children, data regarding the grandparent’s health, life experiences and demographics and data gathered from the grandchildren. This makes the data very flexible and relatable to intergenerational aspects of the family’s life.

A key limitation of the study is the lack of ethnic diversity. At the time of enrolment, the county of Avon was mainly Caucasian, therefore there were too few Black, Asian and Minority Ethnic (BAME) participants (<6% in total) to allow for detailed analysis by ethnic background.

Data availability

Underlying data

ALSPAC data access is through a system of managed open access. The steps below highlight how to apply for access to the data included in this paper and all other ALSPAC data.

    • 2. You may also find it useful to browse our fully searchable research proposals database ( https://proposals.epi.bristol.ac.uk/), which lists all research projects that have been approved since April 2011.
    • 3. Please submit your research proposal ( https://proposals.epi.bristol.ac.uk/) for consideration by the ALSPAC Executive Committee using the online process. You will receive a response within 10 working days to advise you whether your proposal has been approved.

    If you have any questions about accessing data, please email: alspac-data@bristol.ac.uk (data) or bbl-info@bristol.ac.uk (samples).

Ethical approval and consent

Prior to commencement of the study, approval was sought from the ALSPAC Ethics and Law Committee and the Local Research Ethics Committees 2. Informed consent for the use of data collected via questionnaires and clinics was obtained from participants following the recommendations of the ALSPAC Ethics and Law Committee at the time. Questionnaires were completed in the participants own home and return of the questionnaires was taken as continued consent for their data to be included in the study. Full details of the approvals obtained are available from the study website ( http://www.bristol.ac.uk/alspac/researchers/research-ethics/). Study members have the right to withdraw their consent for elements of the study or from the study entirely at any time.

Notes

Competing interests: No competing interests were disclosed.Competing interests: No competing interests were disclosed.

Acknowledgements

We are extremely grateful to all the families who took part in this study, the midwives for their help in recruiting them, and the whole ALSPAC team, which includes interviewers, computer and laboratory technicians, clerical workers, research scientists, volunteers, managers, receptionists and nurses.

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Gamsa A: . A note on a modification of the Parental Bonding Instrument.Br J Med Psychol.1987;60(3):, pp.291–294. , doi: 10.1111/j.2044-8341.1987.tb02745.x


ALSPAC – the Avon Longitudinal Study of Parents and Children – is an extraordinarily rich resource for the study of human development. Between April 1991 and December 1992 more than 14,000 pregnant women living in the Avon area of south west England were recruited into the study, and these women, their partners, and the children they gave birth to have been studied intensively since that time. The study’s reach is not only long, but also broad: it is truly multidisciplinary, and its archives include medical, social, genetic, psychological and environmental data alongside an extensive range of biomarkers. Not surprisingly, researchers worldwide have seized the opportunity to use these rich data to explore the multitude of factors that go to shape development.

Even for seasoned users of ALSPAC data, the sheer scope of the study can at times prove daunting. Here, papers such as Ellis et al’s are especially welcome. The authors provide a detailed account of the data collected in one specific area: the ALSPAC parents’ reports, collected in the earliest stages of the study, of their own exposure to traumatic events in childhood. There is already evidence (some based on ALSPAC data) that such exposures show links with adverse developmental outcomes in the next generation. From a public health perspective it is vital we understand more about such intergenerational influences, how they are mediated, and – most important of all - how they might best be offset. This highly practical guide should do much to encourage other investigators to use ALSPAC data to seek answers to these questions.

One word of caution is in order. One of the great strengths of the ALSPAC data-set is that it is prospective in nature, charting development and exposures as they unfold. But reports of parents’ childhood experiences are inevitably retrospective, reflecting parents’ recall of events and experiences many years in the past. Emerging evidence suggests that retrospective and prospective accounts of childhood adversities are not simply interchangeable: they show moderate agreement, but that agreement is by no means complete (see e.g. Baldwin et al, 2019 1; Newbury et al, 2018 2; Reuben et al, 2016 3). Within the same generation, retrospective reports of childhood adversity relate most strongly to self-reported health outcomes, while prospective reports relate more strongly to objectively observed markers of health. It is unclear at this stage how far (if at all) such differences may impact estimates of intergenerational transmission. As investigators take advantage of the roadmap that Ellis et al provide, however, it would be well for them to have the potential for such variations in mind.

Are sufficient details of methods and materials provided to allow replication by others?

Yes

Is the rationale for creating the dataset(s) clearly described?

Yes

Are the datasets clearly presented in a useable and accessible format?

Yes

Are the protocols appropriate and is the work technically sound?

Yes

Reviewer Expertise:

lifecourse epidemiology

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

Notes

Competing interests: No competing interests were disclosed.Competing interests: No competing interests were disclosed.

References

1 

: . Agreement Between Prospective and Retrospective Measures of Childhood Maltreatment: A Systematic Review and Meta-analysis.JAMA Psychiatry.2019;76(6) : 10.1001/jamapsychiatry.2019.0097, pp.584-593, doi: 10.1001/jamapsychiatry.2019.0097

2 

: . Measuring childhood maltreatment to predict early-adult psychopathology: Comparison of prospective informant-reports and retrospective self-reports.J Psychiatr Res.96: 10.1016/j.jpsychires.2017.09.020, pp.57-64, doi: 10.1016/j.jpsychires.2017.09.020

3 

: . Lest we forget: comparing retrospective and prospective assessments of adverse childhood experiences in the prediction of adult health.J Child Psychol Psychiatry.57(10) : 10.1111/jcpp.12621, pp.1103-12, doi: 10.1111/jcpp.12621


The paper by Ellis et al. is an important contribution to one of the best intergenerational longitudinal studies of human bio-psycho-social development, the Avon Longitudinal Study of Parents and Children (ALSPAC). The paper describes the exceptionally large amount of information that was collected, at the time of pregnancy, on the parents’ traumatic events during their own childhood. 

 We thought that we were very familiar with the content of the ALSPAC study before we read the Ellis et al. paper. However, it made us realise the importance of the information collected on the prenatal and perinatal development of both parents. The paper will most certainly convince other investigators who study intergenerational effects during human development to use this exceptional data set. 

Ellis et al. draw attention to ALSPAC’s abundant information concerning both parents’ life events and mental health during their own childhood and during their child’s development. This is important, because ALSPAC provides a unique opportunity to answer several questions concerning two interrelated dimensions of intergenerational impacts on bio-psycho-social development.

The first, is related to assortative mating processes based on shared life experiences, such as traumatic life events and mental health problems (e.g. Nordsletten et al., 2016 1). The second is intergenerational epigenetic mechanisms. There is increasing evidence that traumatic events during an individual’s development can have epigenetic consequences on his children’s bio-psycho-social development (e.g. Jawaid et al., 2019 2; Perez et al., 2019 3). Because epigenetic data on mothers and children is available from birth onwards, for a subsample of the ALSPAC’s children (see Cecil et al., 2014 4 and Houtepen 2019 5), investigators can study the mechanisms implicated in the association between both parents’ adverse childhood events and their children’s epigenetic profile development. Considering the richness of the ALSPAC database, numerous other mediators and moderators can be included in these analyses.

Are sufficient details of methods and materials provided to allow replication by others?

Yes

Is the rationale for creating the dataset(s) clearly described?

Yes

Are the datasets clearly presented in a useable and accessible format?

Yes

Are the protocols appropriate and is the work technically sound?

Yes

Reviewer Expertise:

NA

We confirm that we have read this submission and believe that we have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

Notes

Competing interests: No competing interests were disclosed.Competing interests: No competing interests were disclosed.

References

1 

: . Patterns of Nonrandom Mating Within and Across 11 Major Psychiatric Disorders.JAMA Psychiatry.2016;73(4) : 10.1001/jamapsychiatry.2015.3192, pp.354-61, doi: 10.1001/jamapsychiatry.2015.3192

2 

: . Inter- and transgenerational inheritance of behavioral phenotypes. Current Opinion in Behavioral Sciences.2019;25: 10.1016/j.cobeha.2018.12.004, pp.96-101, doi: 10.1016/j.cobeha.2018.12.004

3 

: . Intergenerational and transgenerational epigenetic inheritance in animals.Nat Cell Biol.21(2) : 10.1038/s41556-018-0242-9, pp.143-151, doi: 10.1038/s41556-018-0242-9

4 

: . Environmental risk, Oxytocin Receptor Gene (OXTR) methylation and youth callous-unemotional traits: a 13-year longitudinal study.Mol Psychiatry.2014;19(10) : 10.1038/mp.2014.95, pp.1071-7, doi: 10.1038/mp.2014.95

5 

: . Childhood adversity and DNA methylation in two population-based cohorts. Translational Psychiatry.2018;8(1) : 10.1038/s41398-018-0307-3, doi: 10.1038/s41398-018-0307-3

https://www.researchpad.co/tools/openurl?pubtype=article&doi=10.12688/wellcomeopenres.15804.1&title=Traumatic childhood events of parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC)&author=Genette Ellis,Yasmin Iles-Caven,Kate Northstone,Jean Golding,Barbara Maughan,Richard E. Tremblay,Sylvana M. Côté,Marie-Pier Larose,&keyword=ALSPAC,trauma,parent,child,childhood,behaviour,stress,longitudinal cohort,&subject=Data Note,Articles,