|A systematic review of interventions to increase awareness, knowledge, and folic acid consumption before and during pregnancy
|Chivu CM, Tulchinsky TH, Soares-Weiser K, Braunstein R, Brezis M
The authors concluded that interventions to increase awareness, knowledge and consumption had a positive effect on folic acid intakes before and during pregnancy, although average usage reported was less than 25%. The authors discussed the limitations of the mostly retrospective evidence, but poor reporting of the review methods and study details limit the reliability of this review.
To assess the effects of interventions to increase awareness, knowledge and folic acid consumption before and during pregnancy.
The Cochrane Library and MEDLINE were searched. Search terms were reported. Search dates were not reported, but studies published between 1992 and 2005 were eligible for inclusion. References of relevant studies and reviews were screened for additional data. An expert in the field was contacted.
Randomised controlled trials (RCTs), quasi-experimental interrupted time series studies, follow-up studies, case-control studies and before-and-after studies that evaluated any intervention to increase awareness and knowledge and to assess folic acid consumption before and during pregnancy of women of reproductive age (15 to 49 years) and/or health professionals' knowledge about and counselling on folic acid were eligible for inclusion. Included studies had to be published between 1992 and 2005. Studies that reported outcomes only as blood measures of folic acid or prevalence rates of neural tube defects were excluded.
Interventions aimed at women of reproductive age were national or local campaigns. These included printed media (newspapers, magazines, brochures, posters, pamphlets, leaflets, handouts, promotional material), radio or TV, websites, media educational packs, marketing (advertisements, food labels, magnetised reminder, free distribution of folic acid), education and counselling. Interventions aimed at health professionals included printed materials, training, letters, incentives, reminders and information in professional publications. Interventions were placed in medical centres, pharmacies, kindergartens and schools and public places.
Approximately 50% of the studies included women who were pregnant or mothers. Outcomes evaluated were awareness (ever hearing or reading about folic acid), knowledge (having any information regarding folic acid in prevention of neural tube defects or other congenital malformations) and consumption (daily intake before and after conception). Health professionals' knowledge about dosage and duration of folic acid supplementation were assessed. Outcomes were measured using self-administered questionnaires or telephone interviews.
Titles of articles were screened by one author. It appeared that full papers were assessed by more than one author.
Assessment of study quality
Validity was assessed based on criteria developed by the Effective Practice and Organisation of Care Group, Centre for Reviews and Dissemination (CRD), Cochrane Collaboration and other published criteria. These included assessment of sampling method, specification of eligibility criteria, description of non participants, adjustment for potential confounders, losses to follow-up and validity of assessment instrument. Specific questions for each study design (RCT, before-and-after and interrupted-time-series) were also used. Validity was assessed by one reviewer.
Before and after measurements of awareness, knowledge and folic acid consumption were extracted and used to calculate the percentage of women who were aware, knowledgeable about, or taking folic acid following the intervention. The change in the percentage of health professionals with knowledge and giving advice before and after the intervention were calculated. The Χ2 test was used to determine the difference in proportions between results before and after an intervention for an individual study.
The authors stated neither how data were extracted for the review nor how many reviewers performed the data extraction.
Methods of synthesis
The results were combined in a narrative synthesis that described the direction and size of effects. Heterogeneity between studies was assessed using the I2 test.
Results of the review
Thirty one studies were included in the review, although only 23 studies were included in the analysis (n not reported): two RCTs, one quasi experimental interrupted time series, three described as follow-up studies, one case-control study, two before-and-after studies with a control group and 22 before-and-after studies without a control group. There was evidence of selection bias for most studies. Twenty studies reported response rates with a mean of 75% (range 27% to 99%).
One RCT reported increase in knowledge from 14% to 25% (p<0.001) after an intervention aimed at women of reproductive age. Two studies (one RCT and one quasi-experimental interrupted time series) reported an apparent increase in both intervention and control groups for folic acid use. The RCT reported an increase of 26% for the intervention compared with 8% for the control for weekly folic acid use, and 16% for the intervention compared with 12% for the control for daily use. The interrupted time series study reported 5% for the intervention compared with 4% for control for weekly folic acid use.
The remaining studies (variable study designs) reported increases after an intervention aimed at women of reproductive age for the average level of : awareness of folic acid from 60% to 72% (15 studies), most of which were reported to be statistically significant increases (p values not reported for six studies); knowledge of folic acid from 22% to 49% following an intervention (nine studies), with most increases reported to be statistically significant (p values not reported for two studies), although one study found no difference in knowledge after an intervention; and consumption, which increased from 14% to 23% (14 studies) with most studies reporting statistically significant increases (p values not reported for three studies). However, there was evidence of statistical heterogeneity between studies (I2>96%, p<0.00001).
There were statistically significant increases after an intervention in health professionals’ knowledge of: appropriate dosage of folic acid (p<0.0001; two studies); recommended period for folic acid intake (p<0.0001; six studies); and percentage of health care providers who recommended folic acid to women (p<0.0001; five studies).
Interventions to increase awareness, knowledge and folic acid consumption had a positive effect on folic acid intakes before and during pregnancy, although the average usage reported was less than 25%.
Inclusion criteria were clearly described for interventions, participants, outcomes and study design. Some relevant sources were searched, but no attempts were made to minimise publication bias and it was unclear whether efforts were made to reduce language bias. Methods used to select studies, assess validity and extract data were not fully described, so any efforts made to reduce reviewer errors and bias were unknown. Validity was assessed using established criteria; results of the assessment were not reported, which made it difficult for the reader to judge study validity. No details were presented on demographics of participants or the sample sizes in the included studies, which made it difficult to generalise the review findings. Heterogeneity was assessed and differences were reported in study design, interventions and participants; in view of these differences a narrative synthesis was appropriate. The authors appropriately reported limitations of the review in terms of the inclusion of retrospective studies and studies without control groups, use of self-report measurements by participants and the non-representativeness of the sample (although details of this were not reported). Given the poor reporting of this review the conclusions should be treated with caution.
Implications of the review for practice and research
Practice: The authors stated that there was a need for development of strong social marketing strategies to achieve universal uptake of folic acid use during pregnancy or to adopt folic acid fortification of flour.
Research: The authors stated that further research was required to develop effective interventions aimed at increasing folic acid supplement use by women of reproductive age.
Chivu CM, Tulchinsky TH, Soares-Weiser K, Braunstein R, Brezis M. A systematic review of interventions to increase awareness, knowledge, and folic acid consumption before and during pregnancy. American Journal of Health Promotion 2008; 22(4): 237-245
Subject indexing assigned by NLM
Adolescent; Adult; Awareness; Congenital Abnormalities /prevention & control; Dietary Supplements; Female; Folic Acid /therapeutic use; Health Education; Health Knowledge, Attitudes, Practice; Humans; Mass Media; Middle Aged; Outcome Assessment (Health Care); Pregnancy; Preventive Medicine; Time Factors
Database entry date
This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.