BackgroundRecruiting participants for research studies can be difficult and costly. The popularity of social media platforms (eg, Facebook) has seen corresponding growth in the number of researchers turning to social networking sites and their embedded advertising frameworks to locate eligible participants for studies. Compared with traditional recruitment strategies such as print media, social media advertising has been shown to be favorable in terms of its reach (especially with hard-to-reach populations), cost effectiveness, and usability. However, to date, no studies have examined how participants recruited via social media progress through a study compared with those recruited using more traditional recruitment strategies.Objectives(1) Examine whether visiting the study website prior to being contacted by researchers creates self-screened participants who are more likely to progress through all study phases (eligible, enrolled, completed); (2) compare conversion percentages and cost effectiveness of each recruitment method at each study phase; and, (3) compare demographic and smoking characteristics of participants recruited through each strategy to determine if they attract similar samples.MethodsParticipants recruited to a smoking cessation clinical trial were grouped by how they had become aware of the study: via social media (Facebook) or traditional media (eg, newspaper, flyers, radio, word of mouth). Groups were compared based on throughput data (conversion percentages and cost) as well as demographic and smoking characteristics.ResultsVisiting the study website did not result in individuals who were more likely to be eligible for (P=.24), enroll in (P=.20), or complete (P=.25) the study. While using social media was more cost effective than traditional methods when we examined earlier endpoints of the recruitment process (cost to obtain a screened respondent: AUD $22.73 vs $29.35; cost to obtain an eligible respondent: $37.56 vs $44.77), it was less cost effective in later endpoints (cost per enrolled participant: $56.34 vs $52.33; cost per completed participant: $103.66 vs $80.43). Participants recruited via social media were more likely to be younger (P=.001) and less confident in their quit attempts (P=.004) compared to those recruited via traditional methods.ConclusionsOur study suggests that while social media advertising may be effective in generating interest from potential participants, this strategy’s ability to attract conscientious recruits is more questionable. Researchers considering using online resources (eg, social media advertising, matrix codes) should consider including prescreening questions to promote conversion percentages. Ultimately, researchers seeking to maximize their recruitment budget should consider using a combination of advertising strategies.Trial RegistrationAustralian New Zealand Clinical Trials Registry ACTRN 12614000329662; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=365947l (Archived by WebCite at http://www.webcitation.org/6jc6zXWZI)

Introduction The strong link between early-life education and subsequent reduced risk of dementia suggests that education in later life could enhance cognitive function and may reduce age-related cognitive decline and protect against dementia. Methods Episodic memory, working memory, executive function, and language processing performances were assessed annually over 4 years in 359 healthy older adults who attended university for a minimum of 12 months (intervention) and were compared against 100 healthy adult controls. Results Multiple group latent growth curve modeling revealed a significant improvement in language processing capacity over time in the intervention group. No changes were detected for episodic memory, working memory, or executive function. Discussion These results suggest that complex mental stimulation resulting from late-life further education results in improved crystallized knowledge but no changes to fluid cognitive functions.

IntroductionCognitive reserve (CR) and BDNF Val66Met are independently associated with the rate of cognitive decline in preclinical Alzheimer's disease. This study was designed to investigate the interactive effects of these variables on 36-month cognitive change in cognitively intact older adults.MethodsData for this investigation were obtained from 445 community-residing participants of the Tasmanian Healthy Brain Project, who underwent genetic screening and annual assessment of neuropsychological, health, and psychosocial function.ResultsOur main result was that BDNF Val66Met moderated the relationship between baseline CR and change in executive function performance, in that CR-related differences in function decreased across the follow-up period in BDNF Val homozygotes, but became more pronounced in BDNF Met carriers. Similar effects were not observed within the other memory- and language-related cognitive domains.DiscussionInheritance of BDNF Met may be associated with a detrimental influence on the relationship between CR and cognitive change in cognitively intact older adults, but this effect may be restricted to the executive function domain.

The apolipoprotein (APOE) ε4 allele and the Met variant of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism are associated with reduced cognitive function in older adults. The aim of this study was to examine the independent and interactional effect of the APOE ε4 allele and BDNF Val66Met polymorphism on cognitive function in a cohort of healthy older adults who had undertaken further university level education. Multiple group latent growth curve modeling revealed no change in cognitive function over time in APOE ε4-carriers or in BDNF Met-carriers, nor in carriers of both APOE-ε4 and BDNF-Met alleles. Further, the results indicate that allelic variation in either APOE or BDNF does not modify the beneficial effects of a university-based education intervention on cognitive function over a 4-year period following the intervention.

Smoking cessation interventions have traditionally targeted socially disadvantaged women, for good reason: the majority of smoking pregnant women fall into this category. However, despite the significant attention and resources dedicated to antenatal smoking cessation interventions, most are ineffective with only 7.6% of the present sample quitting smoking during pregnancy. This paper may assist in developing more effective antenatal smoking cessation interventions by more clearly describing the profile of maternal smokers who successfully quit during pregnancy. Specifically, this paper highlights the need to acknowledge and address women's relationship status and mental health in order to promote smoking cessation in pregnancy.