Yu 2008.
| Methods | Prospective randomised study | |
| Participants | Included were pregnant women from the following ethnic populations; 45 Indian Asians, 45 Middle Eastern, 45 Black and 45 Caucasian women. Women who did not speak English were only included if a health advocate was able to interpret and a leaflet was provided in their language. Women with pre‐existing sarcoidosis, osteomalacia, renal dysfunction and tuberculosis were excluded from the study |
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| Interventions | Women were randomised within each ethnic group to 3 arms from 27 weeks until delivery: ‐ Group 1 (n = 60) a daily dose of vitamin D (ergocalciferol) at 800 IU; ‐ Group 2 (n = 60) a 1 dose of 200,000 IU of (calciferol); ‐ Group 3 (n = 59) no treatment (not used in the present analysis). Health worker cadre: the study setting was an antenatal unit at St Mary’s Hospital London, United Kingdom. Latitude 51.5º north of tropics. All study personnel and participants were not blinded to treatment assignment. The person seeing the pregnant women allocated the next available number on entry to the trial, and each woman collected her tablets directly from the hospital pharmacy department or her local pharmacy. Study staff roles were not specified. |
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| Outcomes |
Maternal Secondary
Infant Secondary
Laboratory method used for assessment of vitamin D concentrations: not available |
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| Notes | • Start of supplementation:27 weeks GA • Pre‐gestational BMI (kg/m2): unknown/mixed • Supplementation scheme/regimen: daily, stat or none • Skin pigmentation based on Fitzpatrick skin tone chart (Fitzpatrick 1988): not available • Latitude: north of Tropics • Season at the start of pregnancy: not available Source of funding: this study was supported by the Institute of Obstetrics and Gynaecology Trust, Wolfson and Weston Research Centre for Family Health, Imperial College, Du Cane Road, Hammersmith Hospital, London W12 0NN, UK. Dates of the study: April 2007 and November 2007. Declarations of interest among primary researchers: not reported. |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Quote: “Computer generated random number lists were drawn up by an independent researcher, with randomisation in blocks of 15.” |
| Allocation concealment (selection bias) | Low risk | Quote: “The person seeing the pregnant women allocated the next available number on entry to the trial, and each woman collected her tablets directly from the hospital pharmacy department or her local pharmacy.” |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | Study personnel and participants were not blinded to treatment assignment. |
| Blinding of outcome assessment (detection bias) All outcomes | High risk | Study personnel and participants were not blinded to treatment assignment. |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Group 1:n = 60; discontinued the intervention, changed their minds (n = 3), delivered elsewhere (n = 4), declined blood at delivery (n = 1). Group 2:delivered elsewhere (n = 1), declined blood at delivery (n = 1) |
| Selective reporting (reporting bias) | Low risk | All outcomes described in the methods were reported. |
| Other bias | Unclear risk | There is insufficient information to allow judgement. |
25(OH)D: 25‐hydroxyvitamin D AE: Adverse events AUMS: Amrita Vishwa Vidyapeetham Management System ?? BMI: body mass index Ca: calcium CSMMU: Chhatrapati Shahuji Maharaj Medical University DQ: disqualified (medical DQ: disqualified from the study due to medical reasons) DSMC: Data Safety and Monitoring Committee DNA: deoxyribonucleic acid DXA: dual‐emission X‐ray absorptiometry ELISA: enzyme‐linked immunosorbent assay FBS: fasting blood sugar FDA: Food and Drug Administration, USA G: Group GA: gestational age GDM: gestational diabetes mellitus HELLP syndrome: pregnancy complication characterised by Haemolysis, Elevated Liver enzymes, and Low Platelet count HPLC: high‐performance liquid chromatography ICU: intensive care unit IU: international unit IU/d: international unit per day IUI: intrauterine insemination IVF: in‐vitro fertilisation LC: liquid chromatography LMP: last menstrual period
OW/OB: overweight/obese mcg: microgram MS: mass spectrometryNIH: National Institutes of Health (US) MD: Medical Doctor PCO: polycystic ovaries (syndrome) PI: Principal Investigator PROM: premature rupture of membrane PTH: parathyroid hormone RIA: radioimmunoassay UAE: United Arab Emirates USDA: United States Department of Agriculture VDAART: Vitamin D Antenatal Asthma Reduction Trial