Related Experiment Video

Updated: Aug 16, 2026

Rapid Fractionation and Isolation of Whole Blood Components in Samples Obtained from a Community-based Setting
11:31

Rapid Fractionation and Isolation of Whole Blood Components in Samples Obtained from a Community-based Setting

Published on: November 30, 2015

The Oklahoma City bombing study and methodological issues in longitudinal disaster mental health research

Carol S North1

  • 1Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA. NorthC@psychiatry.wustl.edu

Journal of Trauma & Dissociation : the Official Journal of the International Society for the Study of Dissociation (ISSD)
|September 10, 2005
PubMed

Related Concept Videos

Longitudinal Research02:20

Longitudinal Research

Sometimes we want to see how people change over time, as in studies of human development and lifespan. When we test the same group of individuals repeatedly over an extended period of time, we are conducting longitudinal research. Longitudinal research is a research design in which data-gathering is administered repeatedly over an extended period of time. For example, we may survey a group of individuals about their dietary habits at age 20, retest them a decade later at age 30, and then again...
Longitudinal Studies01:26

Longitudinal Studies

Longitudinal studies are also widely used in other medical and social science fields. For instance, in cardiovascular research, they can monitor patients' health over decades to identify risk factors for heart disease, such as high cholesterol or smoking, and evaluate the long-term effectiveness of preventive measures. Similarly, in mental health studies, researchers might follow individuals from adolescence into adulthood to understand the development and progression of conditions like...
Assumptions of Survival Analysis01:15

Assumptions of Survival Analysis

Survival models analyze the time until one or more events occur, such as death in biological organisms or failure in mechanical systems. These models are widely used across fields like medicine, biology, engineering, and public health to study time-to-event phenomena. To ensure accurate results, survival analysis relies on key assumptions and careful study design.
Observational Studies01:11

Observational Studies

Observational studies are a type of analytical study where researchers observe events without any interventions. In other words, the researcher does not influence the response variable or the experiment's outcome.
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One example of...
Post-traumatic Stress Disorder01:27

Post-traumatic Stress Disorder

Post-traumatic stress disorder (PTSD) is a psychiatric condition that arises following exposure to traumatic events such as natural disasters, forced displacement, or severe accidents. It significantly impairs individuals' ability to cope with daily activities and disrupts their emotional and psychological equilibrium.
Symptoms and Behavioral Manifestations
A spectrum of distressing symptoms characterizes PTSD. Recurrent flashbacks, where individuals involuntarily relive traumatic events, are a...
Surveys02:16

Surveys

Often, psychologists develop surveys as a means of gathering data. Surveys are lists of questions to be answered by research participants, and can be delivered as paper-and-pencil questionnaires, administered electronically, or conducted verbally. Generally, the survey itself can be completed in a short time, and the ease of administering a survey makes it easy to collect data from a large number of people.