Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Longitudinal Research

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...

Assessment of the Cardiovascular System I: Subjective Data

Assessment of the Cardiovascular System I: Subjective Data

A thorough health history and physical assessment are essential for identifying cardiovascular disease (CVD) symptoms and distinguishing them from other health issues.
Initial Enquiry
Ask the patient about their primary concern and thoroughly explore all reported symptoms.
Medical History
Investigate past illnesses affecting the cardiovascular system, such as angina, anemia, rheumatic fever, congenital heart disease, stroke, thrombophlebitis, dysrhythmias, varicosities
Inquire about symptoms...

Surveys

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.

Longitudinal Studies

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...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Overnight negative emotion inertia is moderated by evening cortisol levels.

BMC psychology·2026

Same author

Case Report: Overload of a cross-country skier in elite sports, somatoform autonomic disorder, and end-of-career support.

Frontiers in psychology·2026

Same author

Efficacy of a blended counseling intervention (I-PREGNO) on mental well-being of vulnerable mothers postpartum: Findings from a cluster randomized controlled trial.

Journal of consulting and clinical psychology·2026

Same author

Immersive virtual reality psychotherapy for children and adolescents-A systematic review and meta-analysis.

Internet interventions·2026

Same author

Peripheral immune system activity in young psychiatry patients.

Brain, behavior, & immunity - health·2026

Same author

Psychotherapy Process Dynamics and Their Relation to Treatment Success Do Not Differ Across Diagnoses.

Clinical psychology & psychotherapy·2026

Search research articles

Related Experiment Video

Updated: Apr 24, 2026

Functional Near-Infrared Spectroscopy Hyperscanning Study in Psychological Counseling

Functional Near-Infrared Spectroscopy Hyperscanning Study in Psychological Counseling

Published on: January 17, 2025

An intensive longitudinal study on interpretation issues with the PHQ instructions.

Lennart Seizer¹, Günter Schiepek²

¹Department of Clinical Psychology and Psychotherapy for Children and Adolescents, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany; Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital of Tübingen, Germany; German Center for Mental Health (DZPG), Germany.

Journal of Affective Disorders

|April 22, 2026

Summary

This summary is machine-generated.

The Patient Health Questionnaire-9 (PHQ-9) may conflate symptom frequency and burden. This study found weekly PHQ-9 scores primarily reflect a combined signal of frequency and burden, not one over the other.

Keywords:

Depression Ecological momentary assessment Patient health questionnaire

More Related Videos

Validation of a Psychosocial Intervention on Body Image in Older People: An Experimental Design

Validation of a Psychosocial Intervention on Body Image in Older People: An Experimental Design

Published on: May 31, 2021

The Participant-Reported Implementation Update and Score PRIUS: A Novel Method for Capturing Implementation-Related Data Over Time

The Participant-Reported Implementation Update and Score PRIUS: A Novel Method for Capturing Implementation-Related Data Over Time

Published on: February 19, 2021

Related Experiment Videos

Last Updated: Apr 24, 2026

Functional Near-Infrared Spectroscopy Hyperscanning Study in Psychological Counseling

Functional Near-Infrared Spectroscopy Hyperscanning Study in Psychological Counseling

Published on: January 17, 2025

Validation of a Psychosocial Intervention on Body Image in Older People: An Experimental Design

Validation of a Psychosocial Intervention on Body Image in Older People: An Experimental Design

Published on: May 31, 2021

The Participant-Reported Implementation Update and Score PRIUS: A Novel Method for Capturing Implementation-Related Data Over Time

The Participant-Reported Implementation Update and Score PRIUS: A Novel Method for Capturing Implementation-Related Data Over Time

Published on: February 19, 2021

Area of Science:

Psychiatry
Clinical Psychology
Psychometrics

Background:

The Patient Health Questionnaire-9 (PHQ-9) is a widely used depression screening tool.
Concerns exist regarding potential ambiguity in PHQ-9 instructions, specifically the phrase "bothered by," and its alignment with frequency-based response options.

Purpose of the Study:

To investigate whether weekly PHQ-9 scores correlate more strongly with symptom frequency or symptom burden in patients with depression.
To examine the relationship between symptom frequency and burden within the context of PHQ-9 scoring.

Main Methods:

An intensive longitudinal design was employed with 23 depressed patients.
Daily symptom presence and burden were recorded over 1652 days.
Weekly PHQ-9 assessments were completed over 236 weeks.
Mixed-effects models were utilized to analyze within- and between-person effects.

Main Results:

Symptom frequency and burden were highly correlated in the study sample.
Both frequency and burden individually predicted PHQ-9 scores when analyzed separately.
Neither frequency nor burden demonstrated unique predictive effects on PHQ-9 scores when considered jointly.
Weekly changes in PHQ-9 scores appeared to reflect a shared signal of symptom severity.

Conclusions:

The findings suggest that weekly PHQ-9 scores capture a combined measure of symptom frequency and burden.
While person-level heterogeneity in this relationship is possible, it remains uncertain based on current data.
These preliminary results should be considered in conjunction with the established evidence base for the PHQ-9.