An observational study in Vitamin D Deficiency, sponsored by Istanbul Physical Medicine Rehabilitation Training and Research Hospital. Recruiting at 1 site in Turkey (Türkiye). Open to participants aged 20 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-06.
Sponsored by Istanbul Physical Medicine Rehabilitation Training and Research Hospital · Observational
This observational study aims to investigate the relationship between vitamin D deficiency, postural stability, and neuromuscular control mechanisms in adults. The study will compare individuals with vitamin D deficiency and healthy controls.
Participants will undergo a single-session evaluation including surface electromyography and postural stability assessments during standing tasks under different loading and vibration conditions. No invasive procedures, medications, or blood sampling will be performed. Previously obtained routine laboratory results will be used for vitamin D status.
The study is designed to improve understanding of neuromuscular responses associated with vitamin D deficiency and to contribute to future rehabilitation strategies.
This single-center observational study is designed to evaluate postural stability and load-sensitive neuromuscular control mechanisms in adults with vitamin D deficiency.
Participants will be divided into two groups based on their vitamin D status: individuals with vitamin D deficiency and healthy controls. Vitamin D levels will be determined using previously obtained routine laboratory test results. No additional blood sampling will be performed for this study.
All participants will undergo a standardized assessment protocol in a single session. Surface electromyography will be used to record muscle activity during standing tasks under different postural and loading conditions. Measurements will be performed during single-leg and double-leg stance, with and without vibration stimulation. The procedures are non-invasive and do not involve any pharmacological intervention.
Postural stability parameters and neuromuscular response variables will be analyzed and compared between groups. The primary objective is to identify potential differences in reflex modulation and postural control associated with vitamin D deficiency.
The study aims to provide objective data on neuromuscular adaptations related to vitamin D status and to support future research in rehabilitation and balance training.
801 studies on the registry are indexed under Vitamin D Deficiency; 60 are open to participants now.
This study's planned enrollment of 24 is below the median of 138 across 185 observational studies indexed under Vitamin D Deficiency.
Browse Vitamin D Deficiency studies →Istanbul Physical Medicine Rehabilitation Training and Research Hospital is the lead sponsor of 123 studies on the registry; 26 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Adults aged 20 to 40 years recruited from the outpatient clinics of Istanbul Physical Medicine and Rehabilitation Training and Research Hospital. Participants will include individuals with laboratory-confirmed vitamin D deficiency and healthy volunteers with normal vitamin D status.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants with laboratory-confirmed vitamin D deficiency based on routine clinical test results. All participants will undergo standardized non-invasive postural stability and surface electromyography assessments in a single session.
Participants with normal vitamin D status based on routine clinical test results and no history of balance or neuromuscular disorders. All participants will undergo standardized non-invasive postural stability and surface electromyography assessments in a single session.
Postural Stability Parameters
Postural stability parameters measured during single-leg and double-leg standing using force platform and surface electromyography, including postural sway and neuromuscular response variables.
Time frame: Single assessment session (baseline)
Neuromuscular Reflex and Muscle Activation Patterns
Surface electromyography-derived muscle activation and reflex modulation parameters recorded under different loading and vibration conditions.
Time frame: Single assessment session (baseline)
Effect of Loading and Vibration on Postural Control
Changes in postural stability and neuromuscular responses under loaded and unloaded conditions with and without vibration.
Time frame: Single assessment session (baseline)
Plan to share: Yes — De-identified individual participant data will be shared upon reasonable request for academic and research purposes, after publication of the main results. Requests will be reviewed by the principal investigator and data will be provided under a data use agreement.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Supporting documents and de-identified individual participant data will be made available upon reasonable request after publication of the main results. Requests will be reviewed by the principal investigator and shared for academic purposes under a data use agreement.
Access criteria: Access to de-identified individual participant data and supporting documents (study protocol, statistical analysis plan, and informed consent form) will be granted to qualified researchers upon reasonable request for academic and non-commercial purposes. Requests will be reviewed by the principal investigator. Data will be shared through secure electronic transfer under a data use agreement.
Ran from Mar 2026 to primary completion in Sep 2026, 6 months.
Since we started tracking on Sep 25, 2026, the dates moved once, on Oct 6, 2026: primary completion Jun 2026 → Sep 2026 and completion Jul 2026 → Oct 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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