Please select the eligibility criteria that correspond to the clinical trial below.
Title: Vitamin D In the Prevention of Viral-induced Asthma in Preschoolers: a Randomized Controlled Multicenter Trial (DIVA)
Brief Summary: In this 7-month randomized controlled trial, children aged 1 to less than 6 years, with recurrent asthma attacks triggered mostly by colds, will receive a high dose of vitamin D or a placebo every 3.5 months during their usual clinic visit, and a daily supplement of vitamin D or a placebo. This study will test whether children in vitamin D group have less frequent and less severe asthma exacerbations compared with those receiving placebo.The study will also document the safety profile of this strategy.


Options:
A: Inclusion Criteria:

* Medical diagnosis of bronchial asthma
* serum 25(OH)D3 levels \< 30 ng/ml.

Exclusion Criteria:

* smoking habit ≥ 10 pack-years,
* taking vitamin D supplements,
* kidney disease (creat. \> 2 mg/dl),
* hypercalcaemia (corrected with proteins \> 10.5 mg/dl),
* repeat episodes of renal colic,
* any gastrointestinal disease that might interfere with vitamin D absorption,
* severe psychosocial problems,
* pregnant
* breast-feeding
B: * This study is open to all VITAL participants (NCT 01169259). Population includes men 50 years of age or older and women 55 years of age or older in the United States
* Participants who live in selected metropolitan areas of the U.S. (where we set up the infrastructure for clinic or home visits), are eligible for pulmonary function measurements.
C: Inclusion Criteria:

* Age 1-5 years
* Physician-diagnosed asthma (as per the 2015 Canadian Position Paper on the diagnosis of preschool asthma)
* ≥1 asthma exacerbation requiring rescue oral corticosteroids (OCS) in the past 6 months or ≥2 in the past 12 months (as documented by pharmacy/medical records)
* ≥4 upper respiratory tract infections (URTIs) in the past 12 months (as per parental report)
* URTIs as the main asthma trigger (as per parental report)

Exclusion Criteria:

* Intake \> 400 IU/day of vitamin D3 supplements or fish oil in the past 3 months
* Intention to use \> 400 IU/day of vitamin D3 supplements or fish oil in the fall and winter
* Extreme prematurity (\< 28 week gestation)
* No vitamin D supplementation (if breast-fed in the last 6 months)
* Vitamin D restrictive diets, that is, minimal intake of vitamin D fortified milk (\<250 mL/day for 1-3 years or \<375 mL/day for 4-6 years AND no other (or \<200 IU/day) vitamin D supplement
* Recent immigrants from regions at high risk of rickets (in the past 12 months)
* Recent refugees (in the past 12 months)
* Undernourished children
* Other chronic respiratory disease (e.g. Cystic fibrosis, Bronchopulmonary dysplasia) or chronic kidney, gastrointestinal, endocrinological or cardiac diseases, or sickle cell anemia?
* History of bone disorder disease (e.g. rickets, osteomalacia)
* Intake of oral anti-epileptic, diuretic or anti-fungal medications
* Anticipated difficulty with follow-up or with adherence to the intervention or the procedures
D: Inclusion Criteria:

* Diagnosis of sickle cell disease (HbSS, HbSC, HbS Beta-thalassemia)
* Age 3 to 20 years old

Exclusion Criteria:

* Patient (or parent or guardian) unwilling or unable to provide written informed consent (and assent, if applicable)
* Patient unable or unwilling to comply with requirements of the clinical trial
* Participation in other therapeutic clinical trial
* Current diagnosis of rickets
* History of hypercalcemia or diagnosis of any medical condition associated with hypercalcemia, including primary hyperparathyroidism, malignancy, sarcoidosis, tuberculosis, granulomatous disease, familial hypocalciuric hypercalcemia
* Current use of corticosteroids, excluding inhaled steroids
* Current use of anticonvulsants (phenytoin, phenobarbital, carbamazepine)
* Therapy with thiazide diuretics or lithium carbonate
* Known liver or renal disease
* Patients taking medications for pulmonary complications of sickle cell disease not on a stable dose of medications, as defined by a change in medications or doses within the three months prior to study entry
* Patients on chronic red blood cell transfusion therapy
* Absence of baseline record of respiratory events (respiratory infections, asthma exacerbations, episodes of acute chest syndrome) for the preceding year
* Pregnancy

Answer: C