Screening Protocol for Standing-Induced Low Back Pain in Pain Developers

November 11, 2026 updated by: Ala BabajanTabar, University of Tehran

Validation of a Combined Screening Protocol for Predicting Prolonged Standing Induced Low Back Pain in Pain Developers

The goal of this observational study is to learn whether a short screening test can identify healthy young adults who develop low back pain during prolonged standing ("pain developers"). The study includes university students aged 20 to 35 years with no history of clinical low back pain.

The main questions it aims to answer are:

  • How accurately does a combined screening protocol (three simple clinical hip and movement tests plus a 15-minute muscle activity recording of the gluteus medius) identify people who develop low back pain during 2 hours of standing?
  • Can this short protocol be used instead of the standard 2-hour standing test?

Participants will attend two sessions on separate days:

  • Session 1: Participants will complete three clinical tests (self-reported difficulty of a side-lying leg-lifting task, hip rotation range of motion, and a single-leg squat), fill out a pain catastrophizing questionnaire, and stand for 15 minutes while performing a simple manual task, with surface electrodes recording hip muscle activity.
  • Session 2: Participants will stand for 2 hours while performing simple manual tasks and will rate their low back pain every 15 minutes.

Participants who report an increase of at least 10 mm on a 100 mm visual analog scale during the 2-hour standing session will be classified as pain developers. The screening results will be compared with this classification to calculate sensitivity, specificity, and overall accuracy.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
113

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Iran
    • Tehran Province
      • Tehran, Tehran Province, Iran, infosport@ut.ac.ir
        • Faculty of Sport Sciences and Health, University of Tehran

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

20 years to 35 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Healthy university students aged 20 to 35 years living in University of Tehran dormitories, recruited through electronic and paper announcements in dormitories, the faculty, and dormitory online groups.

Description

Inclusion Criteria:

  • Age 20 to 35 years
  • Body mass index between 20 and 28 kg/m2
  • No lifetime history of clinical low back pain (defined as low back pain that led to consulting a physician or physiotherapist, more than 3 days of absence from work or study, or limitation of daily activities)
  • No previous surgery of the lumbar spine, pelvis, or lower extremities
  • No known neuromuscular, vestibular, or visual disorders
  • Able to stand for 2 hours

Exclusion Criteria:

  • Employment in a job requiring prolonged static standing (more than 1 hour per day) during the past 12 months
  • Any pain in the low back or lower extremities at the start of the standing protocol
  • Inability to complete the questionnaires or perform the movement tests
  • Pregnancy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: COHORT
  • Time Perspectives: PROSPECTIVE

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
healthy young adults

University students aged 20-35 years without a history of clinical low back pain, assessed with the combined screening protocol and the 2-hour prolonged standing test.
Diagnostic test: Combined Screening Protocol

Three clinical tests (self-reported active hip abduction, total hip internal rotation range of motion, single-leg squat) and 15-minute surface EMG of the left gluteus medius during standing.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Diagnostic Accuracy (Sensitivity and Specificity) of the Combined Screening Protocol
Time Frame: Index tests at Session 1 (Day 1) compared with the reference standard at Session 2 (within 2-28 days)

Sensitivity, specificity, and overall accuracy (with 95% confidence intervals) of the combined screening protocol (three clinical tests plus gluteus medius EMG gaps) for identifying pain developers, compared with the reference standard (an increase of at least 10 mm on a 100 mm visual analog scale from baseline at any 15-minute timepoint during 2 hours of standing).
Index tests at Session 1 (Day 1) compared with the reference standard at Session 2 (within 2-28 days)

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Pain Developer Status During a 2-Hour Prolonged Standing Test
Time Frame: Baseline (minute 0) and every 15 minutes up to 120 minutes during the 2-hour prolonged standing test (Session 2, 2 to 28 days after Session 1)

Low back pain intensity is rated on a 100-mm Visual Analogue Scale (VAS; 0 = no pain, 100 = worst imaginable pain). Participants reporting an increase of ≥10 mm relative to baseline at any measurement point are classified as Pain Developers; all others are classified as Non-Pain Developers. This classification serves as the reference standard.
Baseline (minute 0) and every 15 minutes up to 120 minutes during the 2-hour prolonged standing test (Session 2, 2 to 28 days after Session 1)
Folkins Three-Test Clinical Cluster Scores
Time Frame: Session 1 (Day 1)

Three clinical tests: (1) self-rated active hip abduction difficulty (0-5 per side, summed 0-10; positive if ≥4); (2) total bilateral passive hip internal rotation measured with a universal goniometer (degrees; positive if >81.6°); (3) non-dominant single-leg squat, trunk score from video analysis (0, 5, 10, 15; positive if >5).
Session 1 (Day 1)
Number of Gluteus Medius EMG Gaps
Time Frame: During a 15-minute standing EMG recording at Session 1 (Day 1)

Number of gaps in glutes medius surface EMG activity during 15 minutes of standing,A gap is defined as a period in which normalized EMG activity falls below 0.5% of maximum voluntary contraction for more than 0.2 seconds. The total number of gaps is reported, compared between pain developers and non-pain developers
During a 15-minute standing EMG recording at Session 1 (Day 1)

Other Outcome Measures

Other Outcome Measures

For clinical trials, a planned measurement described in the protocol that is used to determine the effect of an intervention/treatment on participants. For observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment. Types of outcome measures include primary outcome measure and secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Pain Catastrophizing Scale (PCS) Total Score
Time Frame: Session 1 (Day 1)

Correlation between Pain Catastrophizing Scale total score (range 0-52; higher scores indicate greater catastrophizing) and maximum VAS pain in an exploratory subgroup of participants reaching at least 20 mm VAS.
Session 1 (Day 1)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Tehran

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 23, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
November 13, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
November 13, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 1, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 11, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 12, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 11, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • UT-LBPD-SCREEN-2026
  • IR.UT.SPORT.REC.1405.047 (Other Identifier: Ethics Committee of Sport Sciences, University of Tehran)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

individual participant data will not be shared publicly to protect participant confidentiality, as data sharing was not included in the informed consent. Aggregate results will be reported in publications.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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