Davidson MB, Duran P, Lee ML, Friedman TC High-dose vitamin D supplementation in people with prediabetes and hypovitaminosis D. Diabetes Care. 2013 Feb;36(2):260-6. doi: 10.2337/dc12-1204. Epub 2012 Oct 1.
Endicott J, Nee J Endicott Work Productivity Scale (EWPS): a new measure to assess treatment effects. Psychopharmacol Bull. 1997;33(1):13-6.
Etgen T, Sander D, Bickel H, Sander K, Förstl H Vitamin D deficiency, cognitive impairment and dementia: a systematic review and meta-analysis. Dement Geriatr Cogn Disord. 2012;33(5):297-305. doi: 10.1159/000339702. Epub 2012 Jul 2. Review.
Gameroff MJ, Wickramaratne P, Weissman MM Testing the Short and Screener versions of the Social Adjustment Scale-Self-report (SAS-SR). Int J Methods Psychiatr Res. 2012 Mar;21(1):52-65. doi: 10.1002/mpr.358. Epub 2011 Dec 5.
Geijselaers SLC, Sep SJS, Stehouwer CDA, Biessels GJ Glucose regulation, cognition, and brain MRI in type 2 diabetes: a systematic review. Lancet Diabetes Endocrinol. 2015 Jan;3(1):75-89. doi: 10.1016/S2213-8587(14)70148-2. Epub 2014 Aug 24. Review. Erratum in: Lancet Diabetes Endocrinol. 2015 Jan;3(1):e1.
Grober E, Hall CB, Hahn SR, Lipton RB Memory Impairment and Executive Dysfunction are Associated with Inadequately Controlled Diabetes in Older Adults. J Prim Care Community Health. 2011 Oct 1;2(4):229-33. doi: 10.1177/2150131911409945. Epub 2011 Jun 1.
Holick MF High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006 Mar;81(3):353-73. Review.
Holick MF Vitamin D deficiency. N Engl J Med. 2007 Jul 19;357(3):266-81. Review.
Jorde R, Sneve M, Figenschau Y, Svartberg J, Waterloo K Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial. J Intern Med. 2008 Dec;264(6):599-609. doi: 10.1111/j.1365-2796.2008.02008.x. Epub 2008 Sep 10.
Koutkia P, Lu Z, Chen TC, Holick MF Treatment of vitamin D deficiency due to Crohn's disease with tanning bed ultraviolet B radiation. Gastroenterology. 2001 Dec;121(6):1485-8.
Lee JH, Choi Y, Jun C, Hong YS, Cho HB, Kim JE, Lyoo IK Neurocognitive changes and their neural correlates in patients with type 2 diabetes mellitus. Endocrinol Metab (Seoul). 2014 Jun;29(2):112-21. doi: 10.3803/EnM.2014.29.2.112. Review.
Lips P Which circulating level of 25-hydroxyvitamin D is appropriate? J Steroid Biochem Mol Biol. 2004 May;89-90(1-5):611-4. Review.
McCann JC, Ames BN Is there convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction? FASEB J. 2008 Apr;22(4):982-1001. Epub 2007 Dec 4. Review.
Mitri J, Dawson-Hughes B, Hu FB, Pittas AG Effects of vitamin D and calcium supplementation on pancreatic ß cell function, insulin sensitivity, and glycemia in adults at high risk of diabetes: the Calcium and Vitamin D for Diabetes Mellitus (CaDDM) randomized controlled trial. Am J Clin Nutr. 2011 Aug;94(2):486-94. doi: 10.3945/ajcn.111.011684. Epub 2011 Jun 29.
Munshi MN, Hayes M, Iwata I, Lee Y, Weinger K Which aspects of executive dysfunction influence ability to manage diabetes in older adults? Diabet Med. 2012 Sep;29(9):1171-7. doi: 10.1111/j.1464-5491.2012.03606.x.
Nazarian S, St Peter JV, Boston RC, Jones SA, Mariash CN Vitamin D3 supplementation improves insulin sensitivity in subjects with impaired fasting glucose. Transl Res. 2011 Nov;158(5):276-81. doi: 10.1016/j.trsl.2011.05.002. Epub 2011 Jun 7.
Penckofer S, Kouba J, Wallis DE, Emanuele MA Vitamin D and diabetes: let the sunshine in. Diabetes Educ. 2008 Nov-Dec;34(6):939-40, 942, 944 passim. doi: 10.1177/0145721708326764. Review.
Recker RR, Gallagher R, MacCosbe PE Effect of dosing frequency on bisphosphonate medication adherence in a large longitudinal cohort of women. Mayo Clin Proc. 2005 Jul;80(7):856-61.
Ruff RM, Light RH, Parker SB, Levin HS Benton Controlled Oral Word Association Test: reliability and updated norms. Arch Clin Neuropsychol. 1996;11(4):329-38.
Schlögl M, Holick MF Vitamin D and neurocognitive function. Clin Interv Aging. 2014 Apr 2;9:559-68. doi: 10.2147/CIA.S51785. eCollection 2014. Review.
Smith MA, Else JE, Paul L, Foster JK, Walker M, Wesnes KA, Riby LM Functional Living in Older Adults With Type 2 Diabetes: Executive Functioning, Dual Task Performance, and the Impact on Postural Stability and Motor Control. J Aging Health. 2014 Aug;26(5):841-859. Epub 2014 Jun 4.
Tuligenga RH, Dugravot A, Tabák AG, Elbaz A, Brunner EJ, Kivimäki M, Singh-Manoux A Midlife type 2 diabetes and poor glycaemic control as risk factors for cognitive decline in early old age: a post-hoc analysis of the Whitehall II cohort study. Lancet Diabetes Endocrinol. 2014 Mar;2(3):228-35. doi: 10.1016/S2213-8587(13)70192-X. Epub 2013 Dec 19.
Wallis DE, Penckofer S, Sizemore GW The "sunshine deficit" and cardiovascular disease. Circulation. 2008 Sep 30;118(14):1476-85. doi: 10.1161/CIRCULATIONAHA.107.713339. Review. Erratum in: Circulation. 2009 Jun 2;119(21):e550.
Zahodne LB, Nowinski CJ, Gershon RC, Manly JJ Depressive symptoms are more strongly related to executive functioning and episodic memory among African American compared with non-Hispanic White older adults. Arch Clin Neuropsychol. 2014 Nov;29(7):663-9. doi: 10.1093/arclin/acu045. Epub 2014 Oct 3.
Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.