Vitamin D Insufficiency

25(OH)-Vitamin D and Its Association With Structural and Functional Parameters in Hospitalized Patients With Neurological Diseases

An Investigation of the Effect of Vitamin D Level During Frozen Embryo Transfer (FET) in IVF and Pregnancy Outcomes

Collegiate Athlete Study

ALPCO 25(OH) Vitamin D CLIA Kit - Fresh Versus Frozen Serum and Plasma Stability Study

Vitamin D Homeostasis in Sarcoidosis

Investigating the Impact of Vitamin D Biofortified Tomatoes on Serum Levels of 25(OH)D

Evaluating the Effect of SOLIUS UV Light Source in Improving Vitamin D Status

Efficacy and Safety of Calcifediol vs Placebo in Subjects With Vitamin D Deficiency

Solius UV Light Source in Improving Serum Levels of 25-hydroxyvitamin D

Repeated-dose Safety, Efficacy, Pharmacokinetic and Pharmacodynamic of CTAP101, Immediate-release Calcifediol, High-dose Cholecalciferol, and Paricalcitol Plus Low-dose Cholecalciferol in Patients With Secondary Hyperparathyroidism, Chronic Kidney Disease 3-4 and Vitamin D Insufficiency

Pharmacokinetics and Safety Study of CTAP101 Capsules in Japanese and Non-Japanese Healthy Subjects and Non-Japanese Healthy Subjects

Gene Expression, Metabolomic, Microbiome, and Calcium Metabolism in Response to Varied Vitamin D Dosages

Vitamin D to Improve Nutrition Prior to Bariatric Surgery and Investigate the Relationship With Negative Outcomes

Vitamin D Supplementation and Physical Function in Older Adults

Trial to Assess Vitamin D Requirements in Lactating Women

The Effects of Serum Vitamin D and IVF Outcome

Safety/Efficacy Study of CTAP101 in Chronic Kidney Disease Subjects With Secondary Hyperparathyroidism (SHPT)

Effect of Omega-3 Fatty Acid on Vitamin D Activation

D Vitamin Intervention in VA

Vitamin D Levels and Vitamin D Education in Geriatric Patients