Introduction

Social media recruitment via Facebook Ads seems to be a promising method for large-scale international trials examining the effectiveness of mHealth interventions. However, little is known about this method in terms of strategy, reach, and costs in the context of psycho-oncology. This paper presents the results of the recruitment strategy that was applied in the Untire app study and shows how many participants could be reached using advertisements (i.e., Ads) on Facebook, who participated, and what it cost.

Method

The Untire app study is a randomized controlled trial targeted at cancer patients and survivors across four English-speaking countries (i.e., Australia, Canada, the U.K., and the U.S.A.). Reach was assessed by the number of people who were shown the Ads, who clicked on the Ads, and completed study assessments. Demographic characteristics were gathered from Facebook Ads Manager and from online study assessments to describe who was reached. Costs were assessed by the budget spent and the cost per click for Ads, for reaching the study's landing page, and for completing study assessments. To conduct a powered RCT, we needed 164 12-weeks assessments in both the intervention and the control group.

Results

From March till October 2018, we used 76 Ads, which were presented to 1.2 million people. 37.376 persons clicked on the study link in the Ads, resulting in 755 baseline completers. Most participants were female (92%), middle-aged (55.5 ± 9.79), and came from the U.K. (72%). The total Facebook advertisement costs from March till October 2018 were €17 k, resulting in an average cost of €0.45 per click on the Ads, €5.55 on average for a person reaching the study's landing page, and €14.89 on average per eligible participant. The costs for every baseline and 12-weeks completer were €22.42 and €47.69, respectively.

Discussion

Reaching participants for international mHealth studies in psycho-oncology via Facebook Ads has potential but is costly. The key to reducing costs lies in constant optimization and testing of Ads and refinement of target audience characteristics.

中文翻译：

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通过 Facebook 广告为国际 mHealth 研究招募参与者：Untire App RCT 的经验

介绍

通过 Facebook 广告进行社交媒体招聘似乎是检验移动医疗干预有效性的大规模国际试验的一种很有前途的方法。然而，在心理肿瘤学的背景下，这种方法在策略、范围和成本方面知之甚少。本文介绍了在 Untire 应用程序研究中应用的招聘策略的结果，并显示了使用 Facebook 上的广告（即广告）可以覆盖多少参与者、参与者以及成本。

方法

Untire 应用程序研究是一项随机对照试验，针对四个英语国家（即澳大利亚、加拿大、英国和美国）的癌症患者和幸存者。覆盖面是通过显示广告、点击广告和完成研究评估的人数来评估的。从 Facebook 广告管理器和在线研究评估中收集了人口特征，以描述覆盖的对象。成本通过花费的预算和每次点击广告的成本、到达研究的目标网页和完成研究评估的成本来评估。为了进行有力的 RCT，我们需要在干预组和对照组中进行 164 次为期 12 周的评估。

结果

从 2018 年 3 月到 2018 年 10 月，我们使用了 76 个广告，向 120 万人展示了这些广告。37.376 人点击了广告中的研究链接，导致 755 名基线完成者。大多数参与者是女性 (92%)、中年人 (55.5 ± 9.79)，来自英国 (72%)。从 2018 年 3 月到 2018 年 10 月，Facebook 广告总成本为 17,000 欧元，导致广告每次点击的平均成本为 0.45 欧元，到达研究目标网页的人平均为 5.55 欧元，每位合格参与者的平均成本为 14.89 欧元. 每个基线和 12 周完成者的成本分别为 22.42 欧元和 47.69 欧元。

讨论

通过 Facebook 广告吸引国际 mHealth 心理肿瘤学研究的参与者具有潜力，但成本高昂。降低成本的关键在于不断优化和测试广告，细化目标受众特征。