Please select the eligibility criteria that correspond to the clinical trial below.
Title: Randomised, Multi-centre, Double-blind, Placebo-controlled Trial of Vitamin D Supplementation in Adult and Adolescent Patients With Asthma
Brief Summary: The study null hypothesis is that vitamin D supplementation will not influence time to upper respiratory tract infection or time to severe asthma exacerbation in adult and adolescent patients with asthma.


Options:
A: Inclusion Criteria:

* 6 to 16 years old
* Physician-diagnosed asthma for at least one year
* At least one severe asthma exacerbation in the previous year
* Use of asthma medications (daily controller medication \[ICS or leukotriene inhibitor\] or inhaled β2-agonist \[at least three days per week\]) for at least six months in the previous year
* Vitamin D insufficiency (i.e., serum vitamin D (25(OH)D level \<30 ng/ml (75 nmol/L))
* FEV1 ≥70 % of predicted
* Positive bronchodilator response (i.e., increase in FEV1 ≥8% from baseline after inhaled short acting beta agonist or increased airway responsiveness to methacholine (PC20 ≤8 mg/ml if not on ICS or PC20 ≤16 mg/ml if on ICS)
* Study protocol (i.e., age-appropriate dose of Fluticasone and no other asthma controller medications) approved by the child's regular doctor
* Parental consent and child's assent to participate in the study.

Additional inclusion criteria applied after the run-in period, to be eligible for randomization:

* Adherence with ICS and study medication (≥75% use \[at least 21 of 28 days\]) during the run-in period
* Willingness to be randomized and complete study

Exclusion Criteria:

* Serum calcium \>10.8 mg/dl
* Serum 25(OH) D \<14 ng/ml (35 nmol/L)
* Chronic respiratory disorder other than asthma
* Severe asthma (intubation for asthma at any time OR ≥3 hospitalizations for asthma in previous year OR ≥6 severe asthma exacerbations in previous year)
* Hepatic/renal disease, rickets, malabsorption, or other diseases that would affect vitamin D metabolism
* Current smoking, or former smoking if ≥5 pack-years
* Immune deficiency, cleft palate or Down's syndrome
* Treatment with anticonvulsants or ≥1,000 IU/day of vitamin D2 or D3
* Chronic oral corticosteroid therapy
* Inability to perform acceptable spirometry
* Use of investigational therapies or participation in trials 30 days before or during the study
* Participant is currently breast feeding an infant
* Pregnancy
* Weight less than 10 kg
* Plans to move out of the study site area in the next year

Additional exclusion criteria applied after the run-in period:

* Any severe asthma exacerbation during the run-in period
* Need for asthma medications other than ICS and p.r.n. rescue inhalers during the run-in period
B: Principal Inclusion Criteria:

* Medical record diagnosis of asthma
* Age ≥ 16 years and ≤ 80 years on day of first dose of IMP
* If a woman of child-bearing potential, is sexually abstinent or has negative pregnancy test within 7 days of recruitment and agrees to use reliable form of contraception until she has completed the study
* Able to give written informed consent to participate in the study

Principal Exclusion Criteria:

* Diagnosis of COPD
* Known sarcoidosis, hyperparathyroidism, nephrolithiasis, active tuberculosis, vitamin D intolerance, liver failure, renal failure, terminal illness, lymphoma or other malignancy not in remission for ≥ 3 years
* Any other condition that, in an investigator's judgement, might compromise patient safety or compliance, interfere with evaluation or preclude completion of the study
* Taking benzothiadiazine derivative, cardiac glycoside, carbamazepine, phenobarbital, phenytoin or primidone
* Taking dietary supplement containing vitamin D up to 2 months before first dose of IMP
* Treatment with any investigational medical product or device up to 4 months before first dose of IMP
* Breastfeeding, pregnant or planning a pregnancy
* Baseline corrected serum calcium \> 2.65 mmol/L
* Baseline serum creatinine \> 125 micromol/L
* Smoking history \>15 pack-years
C: Inclusion Criteria:

1. Healthy children by parental report
2. Have reached their 1st birthday but not past their 6th birthday
3. Present to a TARGet Kids! practice for routine primary healthcare prior to viral season (September through November)
4. Parents provide informed consent to participate.

Exclusion Criteria:

1. Children with gestational age \< 32 weeks
2. Children with chronic illness (except for asthma) on parental report which is known to interfere with vitamin D metabolism and increase the risk of respiratory infection
3. Children with a sibling participating in the study to reduce clustering effects.
D: * 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.

Answer: B