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. 2010 May;25(5):297-304.
doi: 10.1007/s10654-010-9431-y. Epub 2010 Feb 11.

A successful implementation of e-epidemiology: the Danish pregnancy planning study 'Snart-Gravid'

Krista F Huybrechts  1 , Ellen M Mikkelsen, Tina Christensen, Anders H Riis, Elizabeth E Hatch, Lauren A Wise, Henrik Toft Sørensen, Kenneth J Rothman
Affiliations

A successful implementation of e-epidemiology: the Danish pregnancy planning study 'Snart-Gravid'

Krista F Huybrechts et al. Eur J Epidemiol. 2010 May.

Abstract

The attraction of being able to use the internet for the recruitment of an epidemiologic cohort stems mainly from cost efficiency and convenience. The pregnancy planning study ('Snart-Gravid')-a prospective cohort study of Danish women planning a pregnancy-was conducted to evaluate the feasibility and cost efficiency of using internet-based recruitment and follow-up. Feasibility was assessed by examining patient accrual data over time, questionnaire-specific response rates and losses to follow-up. The relative cost efficiency was examined by comparing the study costs with those of an alternative non internet-based study approach. The target recruitment of 2,500 participants over 6 months was achieved using advertisements on a health-related website, supported by a coordinated media strategy at study initiation. Questionnaire cycle-specific response rates ranged from 87 to 90% over the 12-month follow-up. At 6 months, 87% of women had a known outcome or were still under follow-up; at 12 months the figure was 82%. The study cost of $400,000 ($160 per enrolled subject) compared favorably with the estimated cost to conduct the same study using a conventional non-internet based approach ($322 per subject). The gain in efficiency with the internet-based approach appeared to be even more substantial with longer follow-up and larger study sizes. The successful conduct of this pilot study suggests that the internet may be a useful tool to recruit and follow subjects in prospective cohort studies.

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Conflict of interest statement

Conflict of interest None declared.

Figures

Fig. 1
Fig. 1
Study recruitment over time (*recruitment-related events: week 0: press release; week 2: advertisement on health-related website www.netdoktor.dk; week 10: publication of article featuring the study in large Danish women's magazine; week 38: press release)
Fig. 2
Fig. 2
Survival curve of time to loss to follow-up in a hypothetical study that attempts to follow all subjects for an entire year, based on the observations in Snart-Gravid
Fig. 3
Fig. 3
Estimated change in study cost with increasing number of study subjects (Panel A) and increasing length of follow-up (Panel B)
See this image and copyright information in PMC

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