Studying Children’s Development
o Research Design: The plan or structure of an
investigation which is determined by the investigator’s
o The first step in any study is to pick a question. The
researcher then reads existing research on their topic to
create a hypothesis (A statement derived from theory
that has not yet been tested).
o The researcher is examining associations between two
or more variables referred to as:
Independent Variable: The behavior or
characteristic believed to influence a particular
outcome or result.
Dependent Variable: The measurable outcome
or result in a research study.
o The most used research designs are: single-subject
cases, correlational studies, longitudinal studies, cross-
sectional studies, cross-sequential studies, and
They differ with complexity, efficiency, and the
kinds of questions they can answer.
o Case Study: An in-depth investigation of one person or
small group of individuals. They provide useful
information about an aspect of development (such as
language, or cognition).
Some of the earliest discoveries about children’s
development have been based on case studies.
A problem with case studies is that it is difficult to
make generalizations because the findings may be
unique to the individual. Another problem is that
there may be observer-bias, which is when the
researcher focuses more on certain aspects of
development than others.
o Correlational Studies: A widely used design for
research studying what different factors influence one
another or go together. Such studies are not able to
test cause-and-effect hypotheses. They tell us which
factors influence or are associated in a positive or
Correlation Co-efficient: The statistic that
measures the strength between two measures.
Expressed in a positive or negative ratio between
-1.0 and +1.0 If the two variables are unrelated, the
correlation would be around 0.
A positive correlation does not mean that
there will be a causal relationship (When
the results of a study indicate there is a
systematic cause-and-effect result between
o Longitudinal Study: A study that collects different
types of data on a regular basis and tracks the
development of a group of children over a number of
They can provide valuable information about
individual development over time. One is able to
see how early events can impact later
development. They allow researchers to identify
differences in behavior at different points of
development. It is also to determine the stability
There are problems with these studies too. They
are expensive and take a long time to complete.
The subjects may become aware of what methods
they are being tested with. The final results must
also be considered in relation to when the study
o Cross-Sectional Study: A study that gathers
information simultaneously on one or more aspects of
development among children of different age groups.
Each age group must choose children of similar ethnic
background, gender, socioeconomic background, among
other things. Before drawing any conclusions, the
researcher would make sure that results are similar for
other ethnic groups.
They are useful for establishing age norms (the
age at which certain characteristics emerge).
There are still some disadvantages to cross-
sectional studies. It doesn’t measure changes in
behavior over time, so it makes an estimate as to
what the changes could be. They cannot provide
information on early determinants of behavior.
Also the participants for each age group must be
carefully selected to make sure the only difference
is age. It also cannot figure out the stability of
behavior over time. o Cross-Sequential Study: A study that follows a group
of different-aged children for 2 to 3 years. It can
reliably identify antecedents and stability of behavior
patterns during the course of the study. Tends to be
more efficient than cross-sectional studies. Although
there are many advantages to them, they are not used
o Experimental Study: Participants are randomly
selected and assigned to a group (experimental or
control). They then receive a treatment or intervention
of some kind. This is presumed to cause a behavior or
outcome. In one group they receive the treatment, and
the other doesn’t. If there I a significant difference
between the two groups then the treatment caused the
behavior, which supports the hypothesis.
Sometimes it is not possible to randomly assign
students to a group, in these cases a quasi-
experimental design (a type of research design
that utilizes comparison groups without random
assignment. Also known as causal-comparative
design) is used.
o Action Research: Research conducted by teachers,
administrators, and other change agents in the school
to improve the educational environment for their
students. The goal of a