ClinicalTrials.gg
Sign In
RecruitingNCT05724316Updated Nov 2, 2023

Effects of Vitamin D on the Behaviours, Mental, and Physical Health of Prisoners

An interventional study of Vitamin D supplement in Mental Wellbeing, Depression, Anxiety and Bone Density, Low, sponsored by Oxford Brookes University. Recruiting at 1 site in United Kingdom. Open to male participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2023-11-02.

Sponsored by Oxford Brookes University · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Primary completion was expected by Jan 2024, 2 years 10 months ago, but the record still lists the study as recruiting.
  • Started Mar 2023; still recruiting 3 years 7 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
110
Allocation
Non-randomized
Ages
18 Years and older
Sex
Male
01

Study summary

This study aims to understand how vitamin D (VD) affects human health. Typically, prisoners are low on vitamin D, as it is difficult to receive through diet, and is mostly obtained via exposure to the sun. The investigators predict that VD supplements could help improve overall mental well-being, as well as improve bone health. The investigators aim to recruit two groups of participants from a United Kingdom (UK) Prison, all of whom will participate via an informed consent process. The first group of prisoners will have chosen to take VD supplements, the second group will have chosen not to take VD supplements. At the start of the study, prisoners will have their bone density and blood VD levels tested. The investigators will also ask participants to complete a series of questionnaires to understand the state of mental well-being at the start of the study. Participants will be asked to complete a food diary to track dietary intake over the following week. Additionally, the investigators are interested in identifying what proportion of participants have a specific genetic makeup relating to their ability to metabolise VD, and participants will be asked to provide a saliva sample to test this. Every month following the start of the study, participants will be asked to complete the same questionnaires and food diary again. On the 3rd month, the investigators will again test the participants' bone density and blood levels of VD, to see whether supplementation has improved participant VD status. This study will run for a minimum of 3 months, up to a maximum of 6.

Read the detailed description

Aim of this research:

This is a quantitative open-label controlled trial, aiming to assess the effect of VD supplementation, within offender populations (male adults 21+), on behaviours, physical and mental health outcomes.

Primary Aims:

  1. To assess the prevalence of VD supplementation within prisons.
  2. To assess VD serum levels among male adult prisoner population.
  3. To assess whether VD supplementation in prisons can lead to improved markers of physical health, for example, grip strength, bone density.
  4. To assess whether VD supplementation in prisons can lead to an overall improvement of mental health wellbeing, including anxiety and depression severity, assessed using validated methods.
  5. To assess whether VD can lead to improved behaviour amongst prisoners, assessed using a self-reported aggression questionnaire, and governor adjudication reports.

Secondary Aims:

  1. To determine whether aim 2 is associated with individual differences in VD metabolism.
  2. To assess overall nutritional content and quality of prison dietary intake.

This research has five hypotheses:

  1. VD supplementation will improve Serum 25-hydroxyvitamin D (VD) levels.
  2. VD supplementation will reduce levels of anxiety and depression within the offender population (measured by GAD-7 and PHQ-9).
  3. VD will improve general mental well-being (measured by WEMWBS).
  4. VD supplementation will improve physical health outcomes within the offender population (measured by VD blood serum level, bone density, and grip strength)
  5. VD supplementation will reduce violence and aggressive behaviours (measured by Buss Perry AQ, and adjudication reports)

Study Design:

A minimum of 100 participants (50 per group) will be sought for recruitment (+10% for attrition). The sample size is based on The Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS) which ideally recommends a minimum of 50 participants per group (100 total) to detect a difference of +/- 5 points. This sample size is calculated using a power of 0.8, at a significance level of 0.05.

Group 1 (experimental group) will be supplemented with VD (1x25ug VD3 cholecalciferol tablet per day), and group 2 will not be supplemented with VD (control group). Upon recruitment, participants will be identified as either taking VD, or not. Participants taking VD will be in Group 1, participants not taking VD will be in Group2 (control).

Baseline Measures:

From Participant:

  1. Demographic information: (age, sex, ethnicity/race, gender, level of education, custodial status and length)
  2. Health measures: (height, weight, body mass index (BMI), grip strength)
  3. Dietary intake: food diary (7-day food diary will be provided to participants)
  4. Self-Reported Questionnaires: Patient Health Questionnaire-9 (PHQ-9) (for depression), Generalised Anxiety Disorder Assessment (GAD-7) (for anxiety), Buss Perry Aggression Questionnaire (AQ) (for aggression), and WEMWBS (for general mental wellbeing)
  5. A survey question regarding time spent outside on average, and the date participant first took supplement (if applicable)
  6. Bone density
  7. Blood analysis (for VD serum) (researcher will be qualified for blood-taking procedures)
  8. Saliva analysis (for genetics)

From Prison

  1. Health history (including medications taking)
  2. Behaviour records (governor/officer reports, adjudication reports)
  3. Mental health history (i.e. any diagnoses/treatment for depression, anxiety, bipolar, schizophrenia, any reports of self-harm/suicide attempts)
  4. Substance use (any misuse history)
  5. Dietary issues (history of hunger strikes)
  6. Date of resident entry to prison and length of stay

After baseline, the following measures will be taken at the end of month 1 and month 2:

From Participant:

  1. Questionnaires: PHQ-9, GAD-7, AQ, and WEMWBS
  2. Log/Question regarding time spent outside

At the end of month 3, the following measures will be taken:

From Participant:

  1. Blood analysis: Serum 25-hydroxyvitamin D (25(OH)D)
  2. Bone density
  3. Grip strength
  4. Weight, height, and BMI
  5. 3- or 7-day food diary (will depend on what is discussed with identified prisons)

And the regular monthly measures:

  1. Questionnaires: PHQ-9, GAD-7, AQ, and WEMWBS
  2. Log/Question regarding time spent outside
02

Conditions studied

  • Mental Wellbeing
  • Depression, Anxiety
  • Bone Density, Low
  • Vitamin D Deficiency
  • Behavior

Keywords

  • Anxiety
  • Depression
  • Behaviour
  • Mental health
  • Mental wellbeing
  • Physical health
  • Bone health
  • Prisoners
03

In context

Depression

8,577 studies on the registry are indexed under Depression; 1,720 are open to participants now.

This study's planned enrollment of 110 is above the median of 81 across 7,063 interventional studies indexed under Depression.

Browse Depression studies →

Lead sponsor

Oxford Brookes University is the lead sponsor of 35 studies on the registry; 6 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
Male
Accepts healthy volunteers
Yes

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.

Inclusion criteria

  • Long-term Residents (with minimum 1 year)
  • Biological Male adults (+18)
  • Have been residents for minimum of 3 months
  • Understanding of the English language

Exclusion criteria

Exclusion Criteria:

  • Short term Residents (\<1 year), residents at end of their sentence
  • Residents with conditions impacting nutrient absorption i.e. Crohn's disease/celiac disease
  • Residents already taking calcitriol (an active form of VD)
  • Any medical condition that would preclude a participant from taking VD supplements
  • Any medical condition which could interfere with VD metabolism
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
110 participants (estimated)

Study arms

  • Experimental
    Vitamin D Group

    All participants in this group will receive cholecalciferol (VD3 25μg) tablets, one to be taken per day.

    Dietary Supplement: Vitamin D supplement

  • No intervention
    Control Group

    Will receive no vitamin D supplements.

Interventions

  • Dietary supplementVitamin D supplement

    N/A (says not to repeat information here)

    Also known as: cholecalciferol (VD3 25μg) tablet

06

What researchers measure

Primary outcomes

  1. Mental wellbeing

    Overall mental well-being as measured by The Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS). WEMWBS uses a five-point scale, with participants required to answer questions recalling from the previous 2 weeks. The minimum score is 14, the maximum score is 70. A high score indicates lower well-being.

    Time frame: Baseline

  2. Mental wellbeing

    Overall mental well-being as measured by The Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS). WEMWBS uses a five-point scale, with participants required to answer questions recalling from the previous 2 weeks. The minimum score is 14, the maximum score is 70. A high score indicates lower well-being.

    Time frame: End of Month 1

  3. Mental wellbeing

    Overall mental well-being as measured by The Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS). WEMWBS uses a five-point scale, with participants required to answer questions recalling from the previous 2 weeks. The minimum score is 14, the maximum score is 70. A high score indicates lower well-being.

    Time frame: End of Month 2

  4. Mental wellbeing

    Overall mental well-being as measured by The Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS). WEMWBS uses a five-point scale, with participants required to answer questions recalling from the previous 2 weeks. The minimum score is 14, the maximum score is 70. A high score indicates lower well-being.

    Time frame: End of Month 3

  5. Vitamin D serum levels

    Assessing the levels of serum vitamin D amongst participants, using blood serum. 25(OH)D of \< 20 ng/ml is considered vitamin D deficiency, and 25(OH)D of 21-29 ng/ml is considered insufficient.

    Time frame: Baseline

  6. Vitamin D serum levels

    Assessing the levels of serum vitamin D amongst participants, using blood serum. 25(OH)D of \< 20 ng/ml is considered vitamin D deficiency, and 25(OH)D of 21-29 ng/ml is considered insufficient.

    Time frame: End of month 3

Secondary outcomes

  1. Rule Violations

    Measured by officer/governor reports and adjudication reports.

    Time frame: Baseline

  2. Rule Violations

    Measured by officer/governor reports and adjudication reports.

    Time frame: End of Month 3

  3. Aggression

    Aggression is measured by Buss-Perry Aggression Questionnaire (AQ). The Buss-Perry AQ consists of 34 statements, which participants answer recalling from the previous 2 weeks. Higher T-scores indicate a higher level of aggression. Participants rate each statement using a 5-point Likert scale. Scores are normalised to a scale of 0-1, with 1 representing the highest level of aggression.

    Time frame: Baseline

  4. Aggression

    Aggression is measured by Buss-Perry Aggression Questionnaire (AQ). The Buss-Perry AQ consists of 34 statements, which participants answer recalling from the previous 2 weeks. Higher T-scores indicate a higher level of aggression. Participants rate each statement using a 5-point Likert scale. Scores are normalised to a scale of 0-1, with 1 representing the highest level of aggression.

    Time frame: End of Month 1

  5. Aggression

    Aggression is measured by Buss-Perry Aggression Questionnaire (AQ). The Buss-Perry AQ consists of 34 statements, which participants answer recalling from the previous 2 weeks. Higher T-scores indicate a higher level of aggression. Participants rate each statement using a 5-point Likert scale. Scores are normalised to a scale of 0-1, with 1 representing the highest level of aggression.

    Time frame: End of Month 2

  6. Aggression

    Aggression is measured by Buss-Perry Aggression Questionnaire (AQ). The Buss-Perry AQ consists of 34 statements, which participants answer recalling from the previous 2 weeks. Higher T-scores indicate a higher level of aggression. Participants rate each statement using a 5-point Likert scale. Scores are normalised to a scale of 0-1, with 1 representing the highest level of aggression.

    Time frame: End of Month 3

  7. Generalised anxiety

    Generalised anxiety disorder as measured by GAD-7. The minimum score is 0, the highest is 21. A higher score indicates higher levels of generalised anxiety.

    Time frame: Baseline

  8. Generalised anxiety

    Generalised anxiety disorder as measured by GAD-7. The minimum score is 0, the highest is 21. A higher score indicates higher levels of generalised anxiety.

    Time frame: End of Month 1

  9. Generalised anxiety

    Generalised anxiety disorder as measured by GAD-7. The minimum score is 0, the highest is 21. A higher score indicates higher levels of generalised anxiety.

    Time frame: End of Month 2

  10. Generalised anxiety

    Generalised anxiety disorder as measured by GAD-7. The minimum score is 0, the highest is 21. A higher score indicates higher levels of generalised anxiety.

    Time frame: End of Month 3

  11. Depression severity

    Depression severity as measured by PHQ-9. Minimum score is 0, with the maximum of 27. A higher score indicates higher levels of depression.

    Time frame: Baseline

  12. Depression severity

    Depression severity as measured by PHQ-9. Minimum score is 0, with the maximum of 27. A higher score indicates higher levels of depression.

    Time frame: End of Month 1

  13. Depression severity

    Depression severity as measured by PHQ-9. Minimum score is 0, with the maximum of 27. A higher score indicates higher levels of depression.

    Time frame: End of Month 2

  14. Depression severity

    Depression severity as measured by PHQ-9. Minimum score is 0, with the maximum of 27. A higher score indicates higher levels of depression.

    Time frame: End of Month 3

  15. Bone density

    Bone density measured by Sonost 3000 bone densimeter.

    Time frame: Baseline

  16. Bone density

    Bone density measured by Sonost 3000 bone densimeter.

    Time frame: End of Month 3

  17. Grip Strength

    Grip strength as measured by a Takei Hand Grip Dynamometer.

    Time frame: Baseline

  18. Grip Strength

    Grip strength as measured by a Takei Hand Grip Dynamometer.

    Time frame: End of Month 3

07

Study locations

1 of 1 sites recruiting
  • HMP Huntercombe
    Henley-on-Thames, RG9 5SB, United Kingdom
    Recruiting
08

References and documents

Individual participant data

Plan to share: No — Due to the nature of the participants included, we are undecided on whether raw data will be shared at this time. This will be reviewed later on with the collaborators.

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Mar 2023 (actual). Primary completion is estimated for Jan 2024, 10 months after the start.

Of 3,468 non-industry interventional studies with no phase under Depression, half reached primary completion within 21 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 41. This study's planned 10 months is below that.

Counting every sponsor, half of 3,566 studies reached it within 21 months; a quarter within 9 and three quarters within 41.

How these figures are worked out, and which studies are left out of them.

Registered
Dec 21, 2022
First posted
Feb 13, 2023
StartActual
Mar 18, 2023
Primary completionEst.
Jan 2024
CompletionEst.
Mar 2024
Last update
Nov 2, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Nov 2, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05724316
Lead sponsor
Oxford Brookes University
Collaborators
HM Prison and Probation Service, United Kingdom, Ministry of Justice, United Kingdom, University of Oxford, Practice Plus Group
Responsible party
Jonathan Tammam (Director Centre for Nutrition and Health, Oxford Brookes University) — Principal investigator
First posted
Feb 13, 2023
Start date
Mar 18, 2023
Primary completion
Jan 2024 (estimated)
Completion
Mar 2024 (estimated)
Last update
Nov 2, 2023

Study contacts

Jonathan Tammam
Contact
jtammam@brookes.ac.uk
+44 (0)1865 483245
Shelly Coe
Contact
scoe@brookes.ac.uk
+44 (0)1865 483839
Jonathan Tammam
principal investigator · Oxford Brookes University

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Studies of the drug tested here: Vitamin D

Other studies in this condition

Depression →

Other studies from this sponsor

Oxford Brookes University

Start the discussion