Department of Psychiatry, Montreal, Canada
RMN, Section of Perinatal Psychiatry, Institute of Psychiatry, London, UK
Department of Adolescent and Young Adult Psychiatry, Institut Mutualiste Montsouris, Paris, France
Royal Holloway, University of London
Section of Perinatal Psychiatry, Institute of Psychiatry, London, UK
Department of Psychology, University of Minho, Braga, Portugal
Iowa Depression and Clinical Research Center, University of Iowa, USA
Department of Neurologic and Psychiatric Sciences, University of Florence, Italy
University Department of Psychiatry, Centre Hospitalier Charles Perrens, Bordeaux, France
Department of Psychology, University College Dublin, Ireland
Department of Psychiatry, University of Vienna, Austria
Child and Adolescent Psychiatry, University of Zurich, Switzerland
School of Postgraduate Medicine, Keele University, UK
TCSPND Group*
Correspondence: Dr Odette Bernazzani, Pavillon Rosemont, Département de Psychiatrie, 5689 Boulevard Rosemont, Montréal, Québec, Canada H1T 2H1. E-mail:o.bernazzani{at}umontreal.ca
* TCSPND Group membership and funding detailed in Acknowledgements, p.
iv, this supplement.
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ABSTRACT |
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Aims With in the context of a cross-cultural study, to establish the usefulness of the CAME, and to test expected associations of the measure with characteristics of the social context and with major or minor depression.
Method The CAME was administered antenatally and postnatally in ten study sites, respectively to 296 and 249 women. Affective disorder throughout pregnancy and up to 6 months postnatally was assessed by means of the Structured Clinical Interview for DSMIVAxis I Disorders.
Results Adversity, poor relationship with either apartner or a confidant, and negative feelings about the pregnancy all predicted onset of depression during the perinatal period.
Conclusions The CAME was able to assess major domains relevant to the psychosocial context of the maternity experience in different cultures. Overall, the instrument showed acceptable psychometric properties in its first use in different cultural settings.
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INTRODUCTION |
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Structure of the CAME
The CAME provides a detailed picture of a woman's life during the
transition to motherhood and enables the assessment of major risk factors for
emotional disturbances, especially depression, in women during pregnancy and
post-partum, using the same instrument and within a coherent methodological
framework. The CAME has three main components: recent life adversity; the
quality of social support and key relationships including partner
relationship; and maternal feelings and attitudes towards pregnancy,
motherhood and the baby. Demographic information is also obtained during the
interview.
Recent life adversity
The recent life adversity assessment provides a continuous measure of
stressors throughout the pregnancy and post-partum period. This assessment was
derived from two specific interview measures: the Adult Life Phase Interview
(Bifulcoet al, 2000)
and the Life Events and Difficulties Schedule
(Brown & Harris, 1978). In
the tradition of these measures, the recent life adversity component focuses
on the level of adversity or the intensity of stressors, which
is an objective, interviewer assessment of relevant circumstances. The
component combines the assessment of both life events and chronic stressors
within eight domains: marital/partner relationship; reproduction and
parenthood, which includes medical or health complications posing a threat to
the pregnancy or to the foetus, and problems concerning the woman's children;
the social arena; work and education; housing and finances; the woman's
health, including pregnancy and birth complications posing a threat to the
mother's health; criminal or legal involvement; and miscellaneous or
geopolitical issues (other potential stressors including geopolitical
difficulties). Adversity is scored on a four-point scale of intensity: 1,
marked; 2, moderate; 3, some; 4, little or none). Each change in adversity
level during the study period is recorded and dated, and categories of
problems are recorded to give further information about the adversity.
Social support and relationships
The social support and key relationships component was adapted from the
Self-Evaluation and Social Support (SESS) measure
(O'Connor & Brown, 1984).
Women are asked about their relationship with two supportive figures named as
being very close or confidants; if the woman has a partner, his
level of support is automatically assessed whether or not he was chosen as a
confidant. Antenatally, for each relationship, seven key topics are assessed:
confiding, emotional support, positive and negative interactions, joint
activity, feelings of attachment, and overall quality of relationship. The
overall quality of relationship scale takes into account and
summarises the other ratings; it is a seven-point scale,
combining a four-point rating scale of supportiveness (very good, good
average, poor average and poor) with an assessment of either the conflicting
or indifferent tone for all but the very good rating. At the
postnatal interview, for each relationship, assessments are made of changes in
overall quality of relationships since the antenatal interview and changes in
emotional support since the baby's birth. Additionally, global assessments are
made of the emotional support received from all others in the woman's social
network since the baby's birth.
Maternal feelings and attitudes
The component evaluating maternal feelings and attitudes towards pregnancy,
motherhood and the baby was adapted from the SESS measure and the Childhood
Experience of Care and Abuse scale
(Bifulcoet al, 1994).
As emotional reactions may fluctuate during the pregnancy, key sub-scales are
rated for two periods: the beginning of pregnancy, and currently (around the
time of prenatal interview). Three topics, measured on a four-point scale, are
included: commitment to the current pregnancy; positive feelings about the
pregnancy; and negative and anxious feelings about the pregnancy. Positive
feelings are assessed separately from negative ones to allow the recording of
potentially contradictory feelings related to maternity. Factual information
about the pregnancy is also recorded, including whether it was planned, if so,
whose decision it was, and the time from the decision being made to becoming
pregnant. Postnatally, this section focuses on the woman's feelings and
attitudes about her baby and motherhood, and provides specific information
about the perinatal context. There are six topics, measured on a four-point
scale: fulfilment in the motherhood role; closeness with the baby; antipathy
towards the baby; how far the baby is perceived as difficult; competence as a
mother; and incompetence as a mother. Information is also obtained about
feelings and attitudes of the woman's partner towards the baby. Key scales are
rated for two periods: the first few weeks following birth, and around the
time of postnatal interview. Information is also collected about the birth and
breast-feeding.
Transcultural Study of Postnatal Depression
The aim of the Transcultural Study of Postnatal Depression (TCSPND)
was to develop (or modify), translate and validate research instruments that
could be used in future studies of postnatal depression in different countries
and cultures. The instruments were chosen to assess key aspects of the
maternity experience, namely clinical diagnosis, the psychosocial context of
pregnancy and motherhood, maternal attachment style, mother-infant
interaction, the child's environment, and health service structure, use and
its associated costs. The modified and translated research tools were piloted
to test how well they worked in a perinatal setting and in different languages
and populations. The use of the CAME to assess the psychosocial context of
pregnancy and motherhood, reported in this paper, is part of the
TCSPND.
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METHOD |
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Sample
Eligible women were approached in antenatal clinics and classes by a
researcher who obtained informed consent from those who agreed to take part.
Antenatally 296 women were interviewed, of whom 249 also completed a postnatal
interview. Demographic characteristics of the sample are described by
Astenet al (2004, this
supplement).
Procedure
Participants were first interviewed during the third trimester of pregnancy
(mean 7.97 months, s.d.=0.91) and again at around 6 months following delivery
(mean 25.83 weeks, s.d.=6.54), except in the Zurich sample where the mean was
17.02 weeks (s.d.=1.57).
Other measures
The Structured Clinical Interview for DSMIV Axis I Disorders
(SCIDI; Firstet al,
1994) is a semi-structured interview for making the major
DSMIV diagnoses (American
Psychiatric Association, 1994). A research version designed for
use with non-patient populations, the SCIDI/NP
(Firstet al, 1996),
was modified for this study to produce an instrument for assessing postnatal
depression in different cultural contexts: the SCIDPND
(Gorman et al, 2004,
this supplement). The SCIDPND was administered at both antenatal and
postnatal interviews, thus providing a continuous assessment of depressive
disorder from the beginning of pregnancy up to 6 months postnatally;
DSMIV diagnoses were made of both major and minor depression, and time
of onset was recorded. The SCIDPND was administered at the same time as
the CAME at both antenatal and postnatal interviews. Complete data from both
interviews at both time points are available for 238 participants, and the
analyses reported here are based on this subsample.
A fifth of the participants (22%; 53 of 238) had an onset of major or minor
depression during pregnancy or within 6 months of delivery. Rates of onset
differed significantly between centres (2=23.12,
P<0.006), from 5% in Zurich to 40% in Bordeaux. Seventeen women
(7%) had an onset of depression in pregnancy, with no significant difference
between centres (range 0% in Dublin and Vienna to 20% in Bordeaux); 41 (17%)
had a post-partum onset, with significant differences between centres
(
2=23.83,P<0.007; range 0% in Florence to 35% in
Paris).
Training and reliability
Interviewers were trained in the use of the CAME at a 4-day workshop at the
University of Keele, with refresher training provided at subsequent workshops.
Each team translated the interview and rating schedules where necessary into
their own language (French, German, Portuguese and Italian). As with other
contextual interviews, the CAME did not require systematic back-translation,
but translators were required to be familiar with the rating system to ensure
that questions would elicit the appropriate material required for rating.
Translations were closely discussed with O.B. and minor adjustments were made
to optimise the clarity of concepts and the flow of the interview in each
language. The English reference manual was retained, as all team members read
English.
Each team provided complete ratings for at least five cases (nearly a fifth of the sample), which were checked for consistency by O.B. The ratings were then discussed in detail in face-to-face meetings between O.B. and each team, and clarifications were made regarding difficult or unclear issues. Subsequent cases were rated on a consensus basis within local teams. Teams kept in close touch with O.B., referring back difficult cases for checking and further consensus. This type of supervision has proved successful in ensuring reliability between raters in other studies using contextual assessments (Broadhead & Abas, 1998; Bifulcoet al, 2000).
Analyses
Data were entered into an Access database prepared by the coordinating
centre and subsequently converted into the Statistical Package for the Social
Sciences for analysis. Analyses were initially conducted separately for the
three CAME components using two strategies. First, comparisons between centres
were carried out using one-way analysis of variance or 2 to
check for significant differences between centres. Second, analyses were
conducted on the pooled data, using t-tests or
2, and
controlling if necessary for centre differences, in order to verify whether
well-known associations between risk factors and depression were replicated
using the CAME. (Data from two participants interviewed in Keele were included
with the London data.) In addition, relationships between CAME components were
examined and a preliminary logistic regression was applied to estimate the
impact of the three CAME components on the occurrence of perinatal
depression.
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RESULTS |
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Analyses of the pooled data indicated a significant association between
severe adversity and onset of perinatal depression
(2=7.92,P<0.005); 29% (37 of 127) of women with
severe adversity experienced a depressive episode compared with 14% (16 of
111) of women without severe adversity, a relative risk ratio of 2.44 (95% CI
1.27-4.69).
Quality of social support during pregnancy
For purposes of comparison between prenatal and postnatal support, the
rating of prenatal overall quality of relationships for each of the two
significant relationships, dichotomised into good (score 1-3) and poor (4-7),
was used in analyses (Table 2). A fifth (19%) of the women had a poor rating for their partner relationship,
with not quite statistically significant differences between centres
(2=15.38,P<0.052) and 8% had a poor rating for
their other significant relationship, with significant differences between
centres (
2=40.39, P<0.001). Overall, 25% of women
had a poor rating for either partner and/or their other relationship, with
significant differences between centres (
2=30.39,
P<0.001). Only 2% of women had a poor rating for both
relationships.
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Overall, poor prenatal overall quality of relationship with the partner was
significantly associated with both antenatal and postnatal onset of
depression. Women with a poor partner relationship were more than three times
as likely to have an antenatal onset of depression (16% compared with 5%:
2=7.03,P<0.008) and more than twice as likely to
have a postnatal onset (30% compared with 14%:
2=6.44,
P<0.01) as women with a good partner relationship. Poor overall
quality for the other significant relationship was also associated with onset
of antenatal depression (
2=5.58,P<0.01) and not
quite significantly with onset of depression postnatally
(
2=3.42,P<0.06).
Quality of social support post-partum
The postnatal support ratings took into account changes in the two key
relationships, and were therefore computed differently. First, any low rating
for overall quality of relationship at any time between the antenatal
interview and the postnatal interview was computed for both of the two key
relationships (Table 2).
Overall 20% of women had at least one poor rating for partner, with
significant differences between centres (2=16.04,
P=0.04) and 13% had at least one poor rating for their other
significant relationship with significant differences between centres
(
2=42.90,P<0.001). A quarter of women (27%) had at
least one poor rating for either of the two relationships, again with
significant differences between centres
(
2=26.44,P<0.001). Only 5% of women overall had a
poor rating for both relationships. Second, any low rating for emotional
support since the baby's birth (3 or 4 on the rating scale) was computed for
both of the two key relationships and for all other
relationships. Overall, 28% of women had at least one poor rating for
partner, with no significant differences between centres, and 24% had at least
one poor rating for their other significant relationship, with significant
differences between centres (
2=30.89,P<0.001).
Large and varying proportions of women in each centre had at least one poor
rating for emotional support from others (
2=44.63,
P<0.001), with an overall rate of 54%. In order to distinguish
women who consistently lacked emotional support, a variable was computed to
take into account low ratings in both key relationships and all other
relationships. Overall, 32% of women had a poor rating in at least two
out of these three categories, with significant centre differences
(
2=29.56, P<0.001 and 6% had a low rating in all
three. Overall, 34% of women had no poor ratings at all (range 6% in Paris to
60% in Iowa City).
Onset of depression in the post-partum period was more than twice as likely
where there was poor overall quality of relationship with the partner (29%
v.13%; 2=6.86,P=0.009), with the other
significant relationship (34% v.15%;
2=6.59,
P=0.01) or with either (30% v.12%;
2=10.24,P<0.001). Onset was also more than twice
as likely where there was a low rating for emotional support from the other
significant relationship (32% v.13%;
2=10.38,P<0.001). A low rating for emotional
support from the partner, however, was not associated with onset of
post-partum depression, and neither was a low rating for support from all
others. Where there was a rating of low emotional support from more than one
source (partner, other significant relationship and others), onset of
depression was more than twice as likely: 29% v.12%
(
2=11.11, P<0.001).
Maternal feelings and attitudes
Antenatally, the internal consistency of the component assessing feelings
at the beginning of pregnancy was good (pooled sample =0.82) and that
for assessing feelings at interview was adequate (pooled sample
=0.75).
For individual centres,
for the scale assessing feelings at the
beginning of pregnancy ranged from 0.64 (Zurich) to 0.89 (Dublin and
Florence), and
for feelings at interview ranged from 0.63 (Iowa City)
to 0.90 (Dublin).
Raw scores were summed to obtain a continuous score reflecting negative feelings. Two separate indices were computed, each on a scale of 3 to 12, the sum of three variables rated 1 to 4. Analysis of variance showed that mean scores varied between centres, with post hoc tests indicating that scores for both initial and current indices were significantly lower in Florence and Zurich than those in all the other centres except Bordeaux. As might be expected, scores on both indices were higher where the pregnancy was not planned: initial index, planned 4.54 (s.d.=1.48) v. unplanned 7.99 (s.d.=2.52), t=12.09, P<0.001; current index, planned 4.51 (s.d.=1.54)v.unplanned 5.73 (s.d.=2.06), t=5.02, P<0.001. Mean scores for the group of women whose pregnancies were unplanned were lower for the current index than the initial index, indicating more positive feelings as the pregnancy progressed. Scores on the current index were significantly higher where there was an onset of depression during pregnancy: 6.29 (s.d.=2.39) v.4.66 (s.d.=1.68), t=2.77, P=0.01. Interestingly, scores on both initial and current indices were also higher where there was postnatal onset of depression: initial index, 6.50 (s.d.=2.12) v.5.28 (s.d.=2.31), t=2.26, P=0.02; current index, 5.44 (s.d.=2.07)v.4.64 (s.d.=1.70), t=2.63, P=0.01.
Postnatally, 16 items reflected feelings occurring at different time
periods: feelings during the first few weeks following birth about motherhood
(three items) and towards the child (three items); and feelings around the
time of postnatal interview about motherhood (three items) and towards the
child (seven items). Internal consistency of the whole component for the
pooled sample was good (=0.83) with all items contributing. For the
individual centres,
was 0.73 or above for all centres except Iowa City
where it was 0.66. The whole component was used in this study to reflect
negative feelings about motherhood and the child both soon after birth and at
interview. As with the antenatal maternal feelings/attitudes component, the
index was a continuous score, computed by summing raw scores on individual
items (reversed as appropriate). Thus, the overall index was on a scale of 16
to 64, the sum of 16 items each rated 1 to 4. Analysis of variance revealed a
difference in mean scores between centres, withpost hoc tests showing
that the Zurich group scores were lower than those of five other centres and
that scores in Porto were lower than those in Bordeaux. For the pooled sample,
scores were significantly higher (indicating more negative feelings) where the
mother had a post-partum onset of depression (t=6.26,
P<0.001) and also where there was an onset of depression in
pregnancy (t=2.48, P=0.01).
Relationships between CAME components
Since there were correlations between CAME components, for example,
adversity with antenatal negative feelings (rs=0.17,
P=0.007) and with a poor relationship at antenatal interview
(rs= 0.12, P=0.05), logistic regression was conducted to
test the effects of each of the components while controlling for the effects
of the others and for study centre. This analysis confirmed that adversity,
poor relationship with partner or significant other and negative feelings
about the pregnancy at the antenatal interview all predicted onset of
depression during the perinatal period, when controlling for study centre
(Table 3).
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DISCUSSION |
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The concurrent validity, and to a lesser extent the predictive validity, of the CAME components were evidenced by their association with perinatal depression. Poor prenatal relationships, especially with partner, were associated with onset of depression both prenatally and postnatally. Prenatal scales reflecting feelings towards the pregnancy were related to onset of depression both antenatally and postnatally, as were the postnatal scales reflecting feelings towards motherhood and the child. Overall adversity was related to the presence of perinatal depression. Logistic regression confirmed that adversity, poor social support and negative feelings toward pregnancy all contributed to the onset of perinatal depression.
The CAME also yielded interesting preliminary results regarding similarities and differences between centres. Rates of severe adversity were high in all samples, ranging from 40% to 71% with a rate of 53% in the pooled sample, possibly reflecting the high risk of women in inner-city areas. A fifth of the sample had a poor relationship with their partner; the lowest rates of poor partner relationship were found in Bordeaux, Zurich and Dublin. More striking differences between centres were found in the quality of relationships with confidants chosen by the women themselves, with prenatal rates of poor relationships ranging from 0% in several centres to an unexpectedly high rate of 41% in Paris. Centre differences among these small, unrepresentative samples cannot be taken to indicate real differences between populations of pregnant and post-partum women. The high rates of employment/education adversity and poor relationships in Paris, for example, may be a spurious finding because of the small numbers in each centre and bias in the selection of cases.
Internal consistency for the component of maternal feelings and attitudes towards pregnancy, motherhood and the baby was adequate for both the prenatal and postnatal scales in the pooled and individual samples. As expected, scores of negative feelings for women with unplanned pregnancies were higher at the beginning of pregnancy than at current interview, suggesting an adjustment to the pregnancy recorded by the CAME.
The CAME is relatively demanding in terms of interview and rating time. It integrates several assessments within the same instrument, based on a coherent theoretical background, thus providing a significant amount of information unavailable elsewhere in a single instrument. This study constitutes a first step in the piloting of the instrument for use in different cultural settings. At this stage, its flexibility and psychometric properties appear sufficiently promising to justify its use to assess the maternity experience in different cultures. Clearly, however, further assessments of the instrument are required in larger, more representative samples of the cultures examined in this study.
In summary, this study indicates that the CAME works well as a means of exploring psychosocial risk factors relevant to the maternity experience in different countries and cultures. These preliminary analyses were carried out in a spirit of piloting and exploration on small samples from a range of countries. Although additional, larger studies are required, our results underscore the potential of the instrument for researchers aiming to study in detail and compare the maternity experience in different settings and cultures.
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Clinical Implications and Limitations |
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LIMITATIONS
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ACKNOWLEDGMENTS |
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