Research Designs and Methods
Researchers use many different designs and methods to study human
development. The three most popular designs are
Cross‐sectional: a number of different‐age individuals with the same
trait or characteristic of interest are studied at a single time.
Longitudinal: the same individuals are studied repeatedly over a
specified period of time.
Cross‐sequential: individuals in a cross‐sectional sample are tested
more than once over a specified period of time.
Seven popular life‐span research methods include the case study, survey,
observational, correlational, experimental, cross‐cultural, and participant
observation methods.
Case-study research
In case‐study research, an investigator studies an individual who has a rare or
unusual condition or who has responded favorably to a new treatment. Case
studies are typically clinical in scope. The investi‐ gator—often a physician,
psychologist, social worker, counselor, or educator—interviews the subject,
obtains background records, and administers questionnaires to acquire
quantifiable data on the subject. A comprehensive case study can last months
or years. Throughout the duration of the case study, the researcher documents
the condition, treatment, and effects in relation to each patient and summarizes
all of this information in individual case reports. A typical case report follows
this format:
1. Presenting problem: The condition or problem.
2. Case history: A brief social history pertinent to the client's presenting
problem.
3. Treatment: A description of the treatment process, including details from
each session.
4. Results of treatment: A description of treatment effects, if any.
5. Follow‐up: A description of the long‐term treatment effects, if any.
Although case studies are valuable for obtaining useful information about
individuals and rare conditions, they tend to focus on the pathology—the
characteristics and effects of a particular disease—and are therefore applicable
only to individuals with similar conditions rather than to the general population.
Survey research
Researchers use many different designs and methods to study human
development. The three most popular designs are
Cross‐sectional: a number of different‐age individuals with the same
trait or characteristic of interest are studied at a single time.
Longitudinal: the same individuals are studied repeatedly over a
specified period of time.
Cross‐sequential: individuals in a cross‐sectional sample are tested
more than once over a specified period of time.
Seven popular life‐span research methods include the case study, survey,
observational, correlational, experimental, cross‐cultural, and participant
observation methods.
Case-study research
In case‐study research, an investigator studies an individual who has a rare or
unusual condition or who has responded favorably to a new treatment. Case
studies are typically clinical in scope. The investi‐ gator—often a physician,
psychologist, social worker, counselor, or educator—interviews the subject,
obtains background records, and administers questionnaires to acquire
quantifiable data on the subject. A comprehensive case study can last months
or years. Throughout the duration of the case study, the researcher documents
the condition, treatment, and effects in relation to each patient and summarizes
all of this information in individual case reports. A typical case report follows
this format:
1. Presenting problem: The condition or problem.
2. Case history: A brief social history pertinent to the client's presenting
problem.
3. Treatment: A description of the treatment process, including details from
each session.
4. Results of treatment: A description of treatment effects, if any.
5. Follow‐up: A description of the long‐term treatment effects, if any.
Although case studies are valuable for obtaining useful information about
individuals and rare conditions, they tend to focus on the pathology—the
characteristics and effects of a particular disease—and are therefore applicable
only to individuals with similar conditions rather than to the general population.
Survey research
