Structured population data were available for 5 of 5 supporting studies. Diabetes type was heterogeneous: 4 studies with type 2 diabetes, 1 studies with type 1 diabetes. 3 studies described adult participants.

3 supporting studies do not have a displayable topic-matched quantitative effect.

Evidence uses heterogeneous comparison contexts: baseline_within_group, placebo, usual_care.

Not extracted from the authoritative source.

Clinician-reference record is usable with limitations in: comparator.

A 12-year-old male child receiving high-dose vitamin D therapy following diagnosis with type 1 diabetes.

High-dose vitamin D therapy

We present the case of a 12-year-old male child who received high-dose vitamin D therapy from 1–27 months following his diagnosis with T1D.

High-Dose Vitamin D May Prolong Remission in Type 1 Diabetes

Available source content was suppressed because validation identified a conflict.

Placebo Group

Core clinician-reference fields are available or not applicable.

Participants received oral vitamin D3 at a dose of 50,000 IU once weekly for 24 weeks.

Vitamin D3 Group

Sixty adult males with established T2DM were randomly assigned to receive oral vitamin D3 (cholecalciferol) 50,000 IU once weekly (n=30) or a matching placebo (n=30) for 24 weeks.

Participants received a placebo vitamin B complex capsule administered orally once weekly for the same duration.

Participants in the control group received a placebo vitamin B complex capsule administered orally once weekly for the same duration.

Authoritative quality diagnostic: invalid or missing unit.

Authoritative quality diagnostic: invalid or missing value.

High-dose vitamin D3 does not improve insulin resistance in type 2 diabetes

Women with pre-diabetes receiving vitamin D supplementation.

Vitamin D Supplementation Group

The intervention group received vitamin D supplementation while control group received lactose granules as placebo.

Women with pre-diabetes receiving lactose granules as placebo.

The control group received lactose granules as placebo.

Authoritative quality diagnostic: sample size arm total mismatch.

Vitamin D may not delay diabetes in women with prediabetes

Standard diabetes care without vitamin D supplementation

Patients received an oral intake of 1000 IU of vitamin D daily for 12 weeks.

Vitamin D supplementation (1000 IU/day)

The intervention group received an oral dose of 1000 IU/day of vitamin D.

Patients received standard diabetes care and educational content about vitamin D.

Although the control group was not provided with 1000 IU of vitamin D, they were informed about the dosage and benefits of taking vitamin supplements.

Vitamin D supplementation improves ankle-brachial index in type 2 diabetes patients

Standard anti-diabetic drugs only

Participants received oral vitamin D3 therapy and continued their prescribed drug therapy for type 2 diabetes for six months.

Vitamin D Group

In one group, the patients were prescribed oral vitamin D3 therapy and continued their prescribed drug therapy for type 2 diabetes for six months.

Participants continued their drug therapy for type 2 diabetes only.

while the other group continued their drug therapy for type 2 diabetes only.

Vitamin D supplementation shows little effect on glycemic control in type 2 diabetes

Structured population data were available for 3 of 3 supporting studies. 1 study described participants with type 2 diabetes. 3 studies described adult participants.

Structured population data were available for 3 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 3 studies described adult participants.

1 supporting study does not have a displayable topic-matched quantitative effect.

1 study contains conflicting p-value and significance fields; those significance claims are suppressed.

Structured population data were available for 4 of 4 supporting studies. 3 studies described participants with type 2 diabetes. 4 studies described adult participants.

Upstream consistency scoring indicates mixed findings across the evidence.

Evidence uses heterogeneous comparison contexts: active_comparator, usual_care.

Structured population data were available for 8 of 8 supporting studies. 4 studies described participants with type 2 diabetes. 8 studies described adult participants.

1 relevant study has unresolved authoritative design evidence and does not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: baseline_within_group, unknown_unresolved, usual_care.

2 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Evidence uses heterogeneous comparison contexts: baseline_within_group, usual_care.

2 supporting studies do not have a displayable topic-matched quantitative effect.

Evidence uses heterogeneous comparison contexts: active_comparator, unknown_unresolved.

3 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 4 of 4 supporting studies. 4 studies described participants with type 2 diabetes. 4 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. Diabetes type was heterogeneous: 2 studies with type 1 diabetes, 1 studies with type 2 diabetes. Age groups were heterogeneous: 2 studies with adult participants, 1 studies with youth participants.

2 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: baseline_within_group, other, usual_care.

4 of 5 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 10 of 11 supporting studies. Diabetes type was heterogeneous: 5 studies with type 2 diabetes, 2 studies with type 1 diabetes. 8 studies described adult participants.

3 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, placebo, unknown_unresolved, usual_care.

1 supporting study lacks usable structured population information.

4 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 8 of 8 supporting studies. 7 studies described participants with type 2 diabetes. 7 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, placebo.

1 supporting study has high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 4 of 4 supporting studies. 4 studies described participants with type 1 diabetes. 2 studies described adult participants.

Structured population data were available for 8 of 8 supporting studies. 6 studies described participants with type 2 diabetes. 7 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, unknown_unresolved, usual_care.

Structured population data were available for 8 of 8 supporting studies. Diabetes type was heterogeneous: 4 studies with type 2 diabetes, 1 studies with type 1 diabetes. Age groups were heterogeneous: 4 studies with adult participants, 1 studies with youth participants.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo, usual_care.

5 of 8 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 3 of 3 supporting studies. 3 studies described participants with type 2 diabetes. 3 studies described adult participants.

3 of 3 studies with duration data have follow-up of 12 weeks or less.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group.

Structured population data were available for 3 of 3 supporting studies. Diabetes type was heterogeneous: 1 studies with type 1 diabetes, 1 studies with type 2 diabetes. 2 studies described adult participants.

Structured population data were available for 13 of 13 supporting studies. 11 studies described participants with type 2 diabetes. 12 studies described adult participants.

4 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, usual_care.

Evidence uses heterogeneous comparison contexts: unknown_unresolved, usual_care.

Structured population data were available for 3 of 3 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. Age groups were heterogeneous: 2 studies with adult participants, 1 studies with youth participants.

Structured population data were available for 12 of 12 supporting studies. Diabetes type was heterogeneous: 9 studies with type 2 diabetes, 1 studies with type 1 diabetes. 12 studies described adult participants.

9 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 5 of 5 supporting studies. 5 studies described participants with type 2 diabetes. 4 studies described adult participants.

Structured population data were available for 3 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 2 studies described adult participants.

Structured population data were available for 2 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 2 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo, unknown_unresolved.

Structured population data were available for 10 of 10 supporting studies. Diabetes type was heterogeneous: 8 studies with type 2 diabetes, 2 studies with type 1 diabetes. Age groups were heterogeneous: 8 studies with adult participants, 1 studies with youth participants.

Evidence uses heterogeneous comparison contexts: active_comparator, other, usual_care.

3 studies contain conflicting p-value and significance fields; those significance claims are suppressed.

Structured population data were available for 4 of 4 supporting studies. 2 studies described participants with type 2 diabetes. 4 studies described adult participants.

Evidence uses heterogeneous comparison contexts: other, usual_care.

2 of 4 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 4 of 4 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. 4 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. 5 studies described participants with type 2 diabetes. 5 studies described adult participants.

Structured population data were available for 11 of 11 supporting studies. 10 studies described participants with type 2 diabetes. 11 studies described adult participants.

Structured population data were available for 6 of 6 supporting studies. 6 studies described participants with type 2 diabetes. 6 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, unknown_unresolved, usual_care.

Structured population data were available for 7 of 7 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. 5 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. 3 studies described participants with type 2 diabetes. 4 studies described adult participants.

Vitamin D supplementation × HbA1c

Available supporting studies

High-Dose Vitamin D May Prolong Remission in Type 1 Diabetes

High-dose vitamin D3 does not improve insulin resistance in type 2 diabetes

Vitamin D may not delay diabetes in women with prediabetes

Vitamin D supplementation improves ankle-brachial index in type 2 diabetes patients

Vitamin D supplementation shows little effect on glycemic control in type 2 diabetes