Hellobee Boards

@runsyellowlites: You probably can see the whole study, though I can (have access to the article). They did a wonderful job controlling for a number of factors.

Child-Level Control Variables
Five child-level demographic variables
were included in themodels: gender, age
in months, low birth weight indicator
(,2500 g), if child was first born, and
mother’s report about the infant’s temperament
assessed at age 1. The temperament
measure used 3 items rated
on a 5-point scale (“not at all” to “very
much”): whether the child often fusses
or cries, is easily upset, and reacts
strongly when upset. The responses are
summed to derive 1 score (range 3–15,
with 15 indicating a highly difficult temperament),
and the measure has been
used to predict earlier spanking behavior
in this data set.10 Table 1 provides
descriptive statistics for all controls.
Maternal and Family Characteristics
The next set of controls focus on maternal
and family characteristics that
are key to understanding the potential
risk and protective factors in the child’s
environment. These include a continuous
variable for the mother’s age at
the time of the birth (in years); the
family marital structure over the
9-year period, from baseline to the age
9 phone interview; the mother’s racial
or ethnic affiliation (these include white,
non-Hispanic; black, non-Hispanic; Hispanic;
and other, comprising Asian Pacific
Islander and American Indian); the
mother’s level of education at baseline;
household income-to-needs ratio at
baseline (ie, the household’s annual income
divided by the relevant family size
poverty line level); maternal foreign-born
status; a dummy variable for whether
the mother reported living with both her

parents when she herself was 15 years
of age; whether the mother was
employed in the week before the age 9
phone interview; the number of other
adults living in the household at age 9;
and the number of other children living
in the household at 9 years of age.
Prenatal Risks
Four variables measure factors from
the prenatal period: late onset of prenatal
care (if carewasinitiated after the
first trimester or not initiated at all),
risky health behavior (if the mother
reported either smoking, taking any
drugs, ormoderate to heavy alcohol use
during pregnancy), whether themother
reported intimate partner violence
(IPV) at the hands of the father before
the child’s birth, and mother’s rating of
the birth father’s supportiveness during
pregnancy based on 4 questions.

Maternal Risk Factors
The next 4 control variables capture
factors reported by the mother that
may be associated with increased risk
for both maternal spanking and child
developmental problems.
Mother’s parenting stress at age 5 was
measured by using a 16-point scale
based on 4 items from the Panel Study
of Income Dynamics–Child Development
Supplement’s Aggravation in Parenting
Scale.22 Items are measured on a 4-
point scale ascertaining the extent to
which the mother agrees that being
a parent is harder than she expected,
she feels trapped by her responsibilities
as a parent, she finds taking care of her
children much more work than pleasure,
and she often feels tired,worn out,
or exhausted from raising a family. The
scale is coded such that a higher score
indicates lower levels of parental
stress, and it has been shown to predict
harsh parenting of preschoolers in this
data set.10
Mother’smental health riskwas assessed
by symptoms indicating depression or
generalized anxiety disorder at any of the
interviews where these concerns were
included. At age 1 and 3, items assessing
both depression and anxiety were included,
whereas at ages 5 and 9, the
interviews contained only items pertaining
to depression. Maternal depressive
symptoms are measured using
an 8-point scale drawn from the Composite
International Diagnostic Interview–
Short Form (CIDI-SF)23 and
scored by assigning 1 point for each affirmative
response. The CIDI-SF depression
measure has been widely used
in previous research and can be coded
as a dichotomous measure of major
depression “caseness” for scores of 3 or
higher.Mothers’symptoms of anxiety are
measured by using the CIDI-SF for generalized
anxiety disorder.24 The stem
conditions coupled with affirmative
responses on at least 3 physiologic
symptoms result in the respondent being
coded with potential generalized anxiety
disorder.25 Finally, we create a single
summary mental health flag variable,
which we set to 1 if the mother is identified
as potentially suffering from either
depression or anxiety at any point in
time, and 0 otherwise.
Mother’s impulsivity was based on 2
questions asked in the age 5 phone
interview about whether she often says
or does things without considering the
consequences and whether she often
gets in trouble for acting before thinking.
26 The response options use a 4-
point scale, with a resulting score
range from 2 to 8, where the higher the
score, the less impulsive is the mother.
Mother’s cognitive level is based on
a modified version of the Similarities
subtest of theWechsler Adult Intelligence
Subscale–Revised (WAIS-R) administered
to the mother at year 3. This subtest
asks the respondent to identify how 2
objects or concepts are comparable. The
values of the modified subscale for the
mother range from 0 (lowest functioning)
to 15 (highest functioning).
The final variable in this group is the
measure of mother’s frequency of potentially
cognitively stimulating activities
with the child at age 1. Specifically,
the age 1 phone interview includes
items asking the mother howmany days
a week she played peek-a-boo with her
child, sang songs or nursery rhymes to
her child, and read to her child. The
positive parenting score reflects the
average of the mother’s responses to
these items. The values, then, range
from 0 (the mother reports never doing
any of these things with her child) to 7
(the mother reports doing all of these
things every day with her child).

But sure... there is always a risk that a study has been poorly done. I'm pretty confident that this one wasn't!

@runsyellowlites: with married at baseline and married at five years, investigators can easily calculate the rest. ( though they do specifically say that they surveyed the family structure every year, so that is taken care of...

The rest is the things you question are all the reasons we do trials that control for things that might confound the study.

I can safely say that this study was exquisitely well designed.