Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
NCT02416193, Phase 2, Terminated, Loyola University; results first posted 2020-10-23
Trial 12
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
| Field | Value | Source |
|---|---|---|
| Title | Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D) | ClinicalTrials.gov |
| NCT number | NCT02416193 | ClinicalTrials.gov |
| Status | Terminated | ClinicalTrials.gov |
| Phases | Phase 2 | ClinicalTrials.gov |
| Enrollment | 56 participants, actual | ClinicalTrials.gov |
| Lead sponsor | Loyola University | ClinicalTrials.gov |
| Conditions | Diabetes, Executive Dysfunction | ClinicalTrials.gov |
| Interventions | Cholecalciferol, Cholecalciferol | ClinicalTrials.gov |
| First posted | 2015-04-14 | ClinicalTrials.gov |
| Last updated | 2020-10-23 | ClinicalTrials.gov |
| Results first posted | 2020-10-23 | ClinicalTrials.gov |
| Limitations and caveats | The trial experienced early termination leading to small numbers of subjects analyzed. | ClinicalTrials.gov |
Registered outcomes 7
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description | Source |
|---|---|---|---|---|
| Primary | Letter-Number Sequencing | 13 weeks | The the Letter-Number Sequencing Test (from the Wechsler Adult Intelligence Scale-III assessment) is an assessment of working memory. Scores on the assessment are standardized as scaled scores with a mean of 10 and standard deviation of 3 (μ = 10, SD = 3) using age adjusted normative data provided by Pearson assessments (https://www.pearsonassessments.com/). A scaled score indicates the number of standard deviations away from the mean. A scaled score of 10 is equal to the mean. Scaled scores below 10 indicate performance is lower than average, and scaled scores higher than 10 indicate performance is higher than average. Higher scaled scores indicate better performance. | ClinicalTrials.gov |
| Primary | Controlled Oral Word Association Test | 13 Weeks | The Controlled Oral Word Association Test is a measure of verbal fluency. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by Tombaugh and Kozak (1996). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance. | ClinicalTrials.gov |
| Primary | Stroop Interference Test | 13 Weeks | The Stroop Interference Test is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by PAR Incorporated (https://www.parinc.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance. | ClinicalTrials.gov |
| Primary | Symbol-Digit Modality Test | 13 Weeks | The Symbol-Digit Modality Test is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by WPS Publishers (https://www.wpspublish.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance. | ClinicalTrials.gov |
| Primary | Trail Making Test Part B | 13 Weeks | The Trail Making Test Part B is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by WPS Publishers (https://www.wpspublish.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance. | ClinicalTrials.gov |
| Secondary | Hopkins Verbal Learning Total Recall Test | 13 weeks | The Hopkins Verbal Learning Total Recall Test is an assessment of memory. Scores are standardized as T-scores (μ = 50, SD = 10) using age adjusted normative data provided by PAR Incorporated (https://www.parinc.com/). A T-score indicates the number of standard deviations away from the mean. A T-score of 50 is equal to the mean. T-scores below 50 indicate performance is lower than average, and T-scores above 50 indicate performance is higher than average. Higher T-scores indicate better performance. | ClinicalTrials.gov |
| Secondary | Semantic Fluency Test | 13 Weeks | The Semantic Fluency Test is a measure of verbal fluency. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by Tombaugh and Kozak (1996). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance. | ClinicalTrials.gov |
Outcomes 7
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as | Source |
|---|---|---|---|---|---|---|
| PRIMARY | Letter-Number Sequencing | 13 weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| PRIMARY | Controlled Oral Word Association Test | 13 Weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| PRIMARY | Stroop Interference Test | 13 Weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| PRIMARY | Symbol-Digit Modality Test | 13 Weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| PRIMARY | Trail Making Test Part B | 13 Weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| SECONDARY | Hopkins Verbal Learning Total Recall Test | 13 weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
| SECONDARY | Semantic Fluency Test | 13 Weeks | The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug. | units on a scale | MEAN | ClinicalTrials.gov |
Results by group 14
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units | Source |
|---|---|---|---|---|---|---|
| Letter-Number Sequencing | Low Dose | 9.13 | Standard Deviation 2.53 | units on a scale | ClinicalTrials.gov | |
| Letter-Number Sequencing | High Dose | 9.00 | Standard Deviation 1.87 | units on a scale | ClinicalTrials.gov | |
| Controlled Oral Word Association Test | Low Dose | -0.35 | Standard Deviation 1.10 | units on a scale | ClinicalTrials.gov | |
| Controlled Oral Word Association Test | High Dose | -0.37 | Standard Deviation 0.93 | units on a scale | ClinicalTrials.gov | |
| Stroop Interference Test | Low Dose | -0.15 | Standard Deviation 0.88 | units on a scale | ClinicalTrials.gov | |
| Stroop Interference Test | High Dose | -0.30 | Standard Deviation 0.96 | units on a scale | ClinicalTrials.gov | |
| Symbol-Digit Modality Test | Low Dose | 0.12 | Standard Deviation 0.82 | units on a scale | ClinicalTrials.gov | |
| Symbol-Digit Modality Test | High Dose | 0.05 | Standard Deviation 1.20 | units on a scale | ClinicalTrials.gov | |
| Trail Making Test Part B | Low Dose | 0.01 | Standard Deviation 0.85 | units on a scale | ClinicalTrials.gov | |
| Trail Making Test Part B | High Dose | -0.10 | Standard Deviation 1.35 | units on a scale | ClinicalTrials.gov | |
| Hopkins Verbal Learning Total Recall Test | Low Dose | 38.07 | Standard Deviation 8.92 | units on a scale | ClinicalTrials.gov | |
| Hopkins Verbal Learning Total Recall Test | High Dose | 39.57 | Standard Deviation 11.50 | units on a scale | ClinicalTrials.gov | |
| Semantic Fluency Test | Low Dose | 0.41 | Standard Deviation 1.46 | units on a scale | ClinicalTrials.gov | |
| Semantic Fluency Test | High Dose | -0.36 | Standard Deviation 0.95 | units on a scale | ClinicalTrials.gov |
Participant flow 6
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted | Source |
|---|---|---|---|---|---|
| Overall Study | STARTED | Low Dose | 15 | ClinicalTrials.gov | |
| Overall Study | STARTED | High Dose | 15 | ClinicalTrials.gov | |
| Overall Study | COMPLETED | Low Dose | 15 | ClinicalTrials.gov | |
| Overall Study | COMPLETED | High Dose | 15 | ClinicalTrials.gov | |
| Overall Study | NOT COMPLETED | Low Dose | 0 | ClinicalTrials.gov | |
| Overall Study | NOT COMPLETED | High Dose | 0 | ClinicalTrials.gov |
Adverse events 58
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
| Type | Event | Organ system | Group | Affected | At risk | Events | Source |
|---|---|---|---|---|---|---|---|
| other | Cold virus | Infections and infestations | Low Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Cold virus | Infections and infestations | High Dose | 4 | 15 | 4 | ClinicalTrials.gov |
| other | Short menstrual period | Reproductive system and breast disorders | Low Dose | 1 | 14 | 1 | ClinicalTrials.gov |
| other | Short menstrual period | Reproductive system and breast disorders | High Dose | 0 | 11 | 0 | ClinicalTrials.gov |
| other | Menstrual cramps | Reproductive system and breast disorders | Low Dose | 0 | 14 | 0 | ClinicalTrials.gov |
| other | Menstrual cramps | Reproductive system and breast disorders | High Dose | 1 | 11 | 2 | ClinicalTrials.gov |
| other | Arm pain | General disorders | Low Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Arm pain | General disorders | High Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Toothache | General disorders | Low Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Toothache | General disorders | High Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Nausea | General disorders | Low Dose | 3 | 15 | 3 | ClinicalTrials.gov |
| other | Nausea | General disorders | High Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Constipation | Gastrointestinal disorders | Low Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Constipation | Gastrointestinal disorders | High Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Cataracts | Eye disorders | Low Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Cataracts | Eye disorders | High Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Hypercalcemia | Endocrine disorders | Low Dose | 0 | 15 | 0 | ClinicalTrials.gov |
| other | Hypercalcemia | Endocrine disorders | High Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Hemorrhoids | Renal and urinary disorders | Low Dose | 1 | 15 | 1 | ClinicalTrials.gov |
| other | Hemorrhoids | Renal and urinary disorders | High Dose | 0 | 15 | 0 | ClinicalTrials.gov |
Adverse event totals 6
The totals the trial posted for each group.
| Total | Group | Affected | At risk | Source |
|---|---|---|---|---|
| Total, all-cause mortality | Low Dose | 0 | 15 | ClinicalTrials.gov |
| Total, all-cause mortality | High Dose | 0 | 15 | ClinicalTrials.gov |
| Total, other adverse events | Low Dose | 12 | 15 | ClinicalTrials.gov |
| Total, other adverse events | High Dose | 9 | 15 | ClinicalTrials.gov |
| Total, serious adverse events | Low Dose | 0 | 15 | ClinicalTrials.gov |
| Total, serious adverse events | High Dose | 1 | 15 | ClinicalTrials.gov |
Papers 40
The papers the trial lists on ClinicalTrials.gov.
| PMID | Listed as | Source |
|---|---|---|
| 2748771 | BACKGROUND | PubMed |
| 3661527 | BACKGROUND | PubMed |
| 6668417 | BACKGROUND | PubMed |
| 9133746 | BACKGROUND | PubMed |
| 11729127 | BACKGROUND | PubMed |
| 12519323 | BACKGROUND | PubMed |
| 14588937 | BACKGROUND | PubMed |
| 15225848 | BACKGROUND | PubMed |
| 16007889 | BACKGROUND | PubMed |
| 16529140 | BACKGROUND | PubMed |
| 17634462 | BACKGROUND | PubMed |
| 18056830 | BACKGROUND | PubMed |
| 18283179 | BACKGROUND | PubMed |
| 18793245 | BACKGROUND | PubMed |
| 18824654 | BACKGROUND | PubMed |
| 19075078 | BACKGROUND | PubMed |
| 20067973 | BACKGROUND | PubMed |
| 20427749 | BACKGROUND | PubMed |
| 20450340 | BACKGROUND | PubMed |
| 21646368 | BACKGROUND | PubMed |
Grants 0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
| Project | Title | Principal investigators | Organization | Funder | Fiscal years | Source |
|---|
Trial comparisons 2
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|---|
| Low Dose vs High Dose: deaths from any cause | Trial comparisons |
| Low Dose vs High Dose: serious adverse events | Trial comparisons |
Tests 6
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
| Test | Named as | Source |
|---|---|---|
| Letter-Number Sequencing Task | Primary outcome | ConductCognition |
| Stroop Color-Word Test | Primary outcome | ConductCognition |
| Trail Making Test B | Primary outcome | ConductCognition |
| Verbal Fluency | Primary outcome | ConductCognition |
| Category Fluency | Secondary outcome | ConductCognition |
| Verbal Learning | Secondary outcome | ConductCognition |
Source 5
| Field | Value | Source |
|---|---|---|
| Release | trials-2026-11-12-0.4.0 | ClinicalTrials.gov |
| Release manifest SHA-256 | 0f4a8d8c48aee2a7573ae0fa94ecbeab70c1adbe449bbc95c424bc7d3e97b9d4 | ClinicalTrials.gov |
| Registry capture | 2026-11-12 | ClinicalTrials.gov |
| Results copy, AACT | 2026-03-23 | ClinicalTrials.gov |
| NIH clinical studies file | 2026-11-13 | ClinicalTrials.gov |
Release trials-2026-11-12-0.4.0
ClinicalTrials.gov's posted results, through CTTI's AACT: ClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299 ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
ClinicalTrials.gov: none stated ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
NIH RePORTER's clinical studies and project files: Public domain (NIH RePORTER)