Solon 1996.
| Methods | Double‐blinded randomised community trial | |
| Participants | 581 children aged 3 to 6 years from 6 barangays (villages) in Silang, Cavite, a province located in the southern part of Luzon, Philippines
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| Interventions | Participants were randomly allocated to 1 of 2 groups: group 1 (n = 296) received fortified margarine containing 862 µg retinol equivalents (108 µg RE from beta carotene plus 754 µg RE added as retinol palmitate per 30 g) vitamin A, 6 mg thiamine,100 µg cholecalciferol (vitamin D3). Group 2 (n = 285) received unfortified margarine containing no vitamins and coloured with annatto. Mothers were instructed to offer the children 1‐2 tablespoons of margarine per day (15‐30 g) and were asked to record the consumption of their study child on a special calender which was collected every week. Households received 250 g of canisters of coded margarine each week.
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| Outcomes | Serum retinol, xerophthalmia, night blindness, Bitot's spots. Measurements taken pre‐ and postintervention (at 6 months). Mean and SDs reported |
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| Notes |
Source of funding: cooperative agreement no DAN 0045 between the Office of Health and Nutrition, and the US Agency for International Development, USA Dates of the study: not reported Declarations of interest among primary researchers (or state where this information is not reported by the trial authors): there are no conflicts of interest disclosed |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Comment: insufficient information to permit judgement |
| Allocation concealment (selection bias) | Unclear risk | Comment: insufficient information to permit judgement |
| Similarity of baseline characteristics (checking for confounding, a potential consequence of selection bias) All outcomes | Low risk | Comment: "children‐receiving vitamin A fortified margarine coming from poorer villages and households. Reported dietary vitamin A and protein intakes, on the other hand, were higher in the experimental group." "Results were adjusted for baseline imbalances that might have been expected to influence vitamin A status by stratification, analysis of covariance to multiple linear regression." |
| Similarity of baseline outcome measurements (checking for confounding, a potential consequence of selection bias) All outcomes | Low risk | Comment: The levels of serum retinol and fat intakes were similar in both groups. |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | Quote (report): "The non‐refrigerated margarine were prepared and coded. Households received 250 g canisters of coded margarine each week. Double masked RCT" |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | Quote (report): "double masked RCT" Comment: no details available. However, laboratory outcomes likely to be low risk |
| Incomplete outcome data (attrition bias) All outcomes | High risk | Quote (report): "581 of 717 contributed to the analysis, 84% (n = 296) in the experimental group and 81% in the control group. Children who had not followed up had moved, were on vacation, were non‐participative at 6 months follow‐up, were deemed non‐compliant during intervention or had baseline serum retinol levels done at Manila because of power shortage and consequence laboratory difficulties, were later excluded when all other specimens were shipped to Thailand for analysis" |
| Contamination (checking for possible performance bias) | Low risk | Quote (report): "Six villages randomly assigned in 2:1 ratio to receive either the fortified (N=4) or non‐fortified (N= 2) margarine" Comment: randomisation at village level |
| Selective reporting (reporting bias) | Low risk | Comment: all the predefined outcome measures were reported |
| Other bias | Low risk | Comment: we did not detect any other source of bias |