Top 5 platforms for recruiting clinical study participants

There are many ways to recruit participants for clinical research studies. For scalability, almost nothing beats paid ads on the biggest websites on the internet, which we refer to as “platforms” due to their social and interactive nature. But which platforms are more effective, measured by bang-for-buck or speed of recruitment, depends highly on the study requirements and some platform-specific factors that we will now guide you through.

Here are the top 5 digital platforms that we recommend you use when recruiting for clinical trials in America, Australia or Europe:

1. Craigslist

Craiglist is a fantastic place to recruit for research studies – especially good for healthy volunteer studies with a high compensation. Craigslist is highly influenced by these factors:

  • Limited targeting.

The only targeting options are geographical and the website category you choose. That makes it have limited use for rare conditions, and hard to use for nationwide studies. Healthy targeting works well though, such as vaccine studies, smoking cessation or a condition that has greater than 1% prevalence.

This is how Craiglist currently splits USA up, with separate directories for each:

Craigslist map of US directories.

A map showing how Craigslist splits the USA up into separate directories. To advertise in each you need to post a separate ad.

  • Compensation is a must.

Another huge factor is compensation. In the jobs or gigs category, which are the two most logical places to put clinical research ads, people are scanning every ad for compensation before all else. In fact – these categories have a special field for payment that is extremely visible.

A specific total sum is best, if you can get that approved by your ethics board: “Participants will be compensated up to $1200 upon completion of this study”. ” […] reimbursed for travel and other expenses related to study visits” is ad copy that usually goes through IRB with no problem. “Per visit” compensation is not ideal, but better than nothing – combine sums into a total if at all possible. This copywriting advice is true for all ads, but it’s critical for craigslist.

  • Post Frequency

Craigslist does not want you to post duplicate ads – not even in separate categories. But if that were allowed it would be ideal. Instead what you need to do is republish the same ad very frequently, even though it means removing the one you paid to have up for 30 days.

The most recent ads are shown first in any given category. And both jobs and gigs are very active categories with hundreds of new ads every day. That means your ad will very quickly be buried under thousands of others, and can only be found by using the search function.

The downside is that payment is due each time you repost an ad, but it’s a low cost at around $35 depending on your geographical region and category. Gigs is a cheaper section, that is often free – especially in Australia.

2. Facebook

Facebook is great for clinical research recruitment for several reasons: 2.4 billion active users (June 2019) being chief among them. Here are some things that affect recruitment efforts on Facebook:

  • Incredible targeting

Facebook and Instagram share an incredible backend for advertisers that allows extremely granular targeting.

You want women aged 52-54, divorced with teenagers, likely to have high BMI, on zipcode 12345, using an iPhone version x.x who are awake in the middle of the night? No problem. Here’s a thousand of them for $20-60 per 1000 views. You can, of course, exclude people based on these same factors too – Smoking, gender, age and exercise being very common.

Then there are custom audiences, different conversion objectives, and types of bidding, etc. Unlike Craigslist it can get quite technical, which is why we would not recommend you run Facebook ads without the help of an agency. (Like Wayturn!)

The targeting becomes better and better the more ads you’ve ran too. Because once you have recruited for one asthma study in Boston, you can feed those people back into the targeting for another asthma study in San Francisco in what’s called a “Lookalike” audience. Pure interest campaigns often underperform in comparison. One great option is also to run an intersection of lookalike audiences and interests to guide Facebook further in who you want to reach.

  • Huge audience

Studies that need participants with quite rare conditions are wise to use Facebook. The platform boasts several billion users, and like it says above 2.4 billion of them are active in any given month. This makes it incredible for rare conditions if you can formulate a strategy to reach them.

But despite the huge diversity of interests on Facebook, it’s not magical. People must join groups, socialize or talk about their interests for Facebook to know that they have them so you can target them with ads. Sexually transmitted diseases or other shameful conditions are rarely talked about, so then the best option becomes to target factors that make STI’s more likely – like alcohol or partying. Accurate prejudice pays off here…

  •  Social sharing and sensitivity

Facebook ads are very frequently shared with other people, both inside and outside the platform, if there are clear benefits to participating. This significantly boosts the number of people that see your ad, and often get you in front of audiences that are impossible to reach and extremely relevant – such as private Breast Cancer support groups that you would otherwise need an invite to join.

However, the social nature of Facebook means that ads, images or even just phrases often annoy people – especially when it comes to research studies.

“Why don’t you study children with Autism?”, “Is this vaccine study just preying on older people?”, “This image is offensive to veterans with PTSD!”…

Facebook comments on a PTSD Research Study, showing controversy.

Controversial PTSD Research study comments on Facebook.

The good news is that this controversy makes ads cheaper – Facebook interprets it as engagement and lowers the cost to reach more people because the ad is perceived to be of high quality. But it’s often not desirable, because annoyed people do not join research studies and it also reflects badly upon your brand.

3. Instagram

While Facebook and Instagram do share the same backend – meaning data, targeting options and statistics – they are different in several ways for clinical research recruitment purposes.

  • Ads must be visual

Newsfeed ads on Instagram do not have headlines – they do not show much of the ad text either unless the reader clicks “See more”. This means that your message must be visual. Video ads are strongly preferred on Instagram whereas they are optional, albeit often better, on Facebook.

Text on images works well, as do subtitles on videos. Videos autoplay on mute and sound feels quite intrusive to most people scrolling through their newsfeeds. Spokesperson videos are NOT always better than straight slideshows or relevant stock videos with a good voice over, contrary to what most advertisers might assume.

The key, as on all platforms, is to catch the attention of the right audience through whatever means is available. On Instagram, the playing field is reduced to almost purely the visual.

  • Different demographics

10% of all Americans aged 65+ have used Instagram, compared to 62% for Facebook. That’s a major difference but some research studies will still do well on for older people on Instagram. Check out the overview below for more detailed demographic info for America for the two platforms:

Instagram and Facebook demographics overview in America

Instagram and Facebook demographics overview in America

  • Different social behavior

Facebook users share posts and discuss much more frequently – even when it’s an exciting research study that pays well. Although this is to some extent compensated by the fact that Instagram is generally cheaper per 1000 views (CPM) than Facebook is. We rarely get the long comment chains going on controversial studies.

4. Google Ads

The search engine king of the world – if you are not recruiting people from Google for your research studies you are missing out. In contrast to people on social media though, these are people in motion. They searched for something because they’re looking for that particular thing. Going broad is rarely effective – we need to be smarter than that.

  • Uncommon Keywords

Most advertisers on Google have a product or service to sell – so the clinical trial recruitment terms are often very cheap. On Facebook and Instagram you compete with other advertisers much more directly, since a lot of products and services are viable for many people. Not so for search terms.

Here’s an example overview of a few basic “cancer research” terms and volumes in America:

Overview of google ads keywords for clinical research recruitment

Example terms for cancer research recruitment on Google Ads.

  • Immediate & Relevant

Everyone uses Google – especially when they feel sick or worried about something. People search for condition related terms all the time. That makes it a great place to recruit for clinical research studies, as these people are showing an active interest in that particular topic RIGHT NOW – compared to the interests on Facebook or Instagram where “Cancer” might be something they were talking about years ago.

Showing them an ad for a research study when they search for one is incredibly powerful. The biggest obstacle is the keyword research to come up with cheap keywords with good volumes that are relevant. The example above estimates 2,400 searches every month in all of America for “Clinical cancer research”. That’s not a lot of volume, although quite relevant. Another thing you need an agency to investigate for you.

  • Not Visual

In stark contrast to Instagram, Google search ads are pure text. Very short texts too. This means that your promotional material needs a special section made specifically for Google ads. The keyword research process needs to be done first too because relevance is the name of the game. To catch people’s attention in a world of no images, the headline of your ad needs to match exactly what they searched for. And with the keyword research process being quite long and important, this is a significant time investment – albeit a very worthwhile one when it pays off.

5. Youtube

Youtube is similar to Google search ads in that they are immediate – you can target people watching only a particular video, channel or whole slew of topics at once. And as the platform is owned by Google we can do some neat tricks with cross-targeting that are highly effective.

  • Targeting

Youtube’s targeting rivals Facebook – there’s targeting based on what people watch, search for and like – or channel and specific video targeting as mentioned above.

Youtube is particularly effective in instances where Facebook’s social nature is a drawback, or the topic is sensitive. Sexually transmitted diseases often have informative videos that can be used as basis for targeting – whereas very few people would openly ask questions about chlamydia on Facebook or Instagram. Disabling comments is not an option for Facebook ads, but it is for Youtube, so that’ another thing to consider if your study requires that kind of discretion.

  • Video required

You can run banner ads on Youtube, but those 5 unskippable video seconds are where it’s at. Trust me. And to catch someone’s attention in 5 seconds you need a well-crafted video.

We have found that starting with your IRB-approved promotional material and creating a voiceover, and then adding that over a selection of stock videos works quite well. Ideal would be to show footage from your research site, patient testimonials, and maybe a doctor interview depending on the study, but that’s quite unrealistic unless it’s a huge sponsor study with a long recruitment timeline.

  • Few competitors

Do not misunderstand, there are plenty of other advertisers but unlike Craigslist, Instagram, Facebook and Google search ads – there are very few research recruitment ads. The creative hurdle of creating a video that works on Youtube may be substantial enough for most recruitment companies to not prioritize the platform. Huge mistake. Finding success on one of the ‘easier’ platforms often means that Youtube is deprioritized if your advertising company is not proactive.

Why more than one platform?

So, given all this information – where should you advertise your research study? “Everywhere” is the answer, of course. Each platform has its own unique audience. To get the maximum speed and lowest cost per enrolment, you need to do all of them – ideally at once.

You will find, however, that a study will often work extremely well on one or two platforms, and get much less traction on the others. This is normal. As discussed above the characteristics and quirks of each platform makes “Cancer” studies cheaper on Google ads, “Quit Smoking” more effective on Facebook (people like to show off positive personal development!) and “STI” research cheaper on Youtube.

But your promotional materials are also probably more suited to one or two platforms, as well as the study itself – the audience you need to reach, the inclusion and exclusion criteria, the demographics, the timeline, the location(s).

The best solution to the problem of WHERE to advertise online is to have the capability and knowledge to advertise effectively on all platforms – as well as search for new ones. We’re actively testing out Spotify, Snapchat, TikTok, LinkedIn and a host of other services you haven’t yet heard of. Ask us this question again in ten years, and the answer will probably surprise both you and us. But for now, make sure your advertising is on point for the above 5 and you’ll be set for 80% of all research studies – for the remaining 20%, we might have to dig deeper.

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