Every clinical researcher is familiar with the struggle of getting in contact with trial volunteers on the phone. However, if you employ the following tips you can maximize your rate of contact, increasing participant engagement and overall enrollment numbers.

• Allow the participants to choose a time they know will work for them.
• Be flexible by having appointments available throughout the day, including early mornings, evenings, and weekends.
• Call when you say you will. Asking people when they want to be contacted and not calling at that time significantly hurts your credibility.
• If you’re unable to make the appointed time, reach out to the participant and ask them to reschedule, or have backup team members who can call them in your place.
• Call them back when they’ve asked you to and provide resolutions within 24 hours. Be willing and able to hop on a call at any time to accommodate their needs.
• Ask for and use the participant’s preferred contact window. If they haven’t answered the first call, try to time your follow-ups to coincide with the preferred time.
• Leverage technology, like Trialfacts’ phone screen appointment system, to automate reminders and block out availability when phone screeners are not available.
• If the participant doesn’t answer the phone during their initial phone screen appointment time, leave a personalized voicemail message and follow up immediately with an email providing a link to reschedule the appointment.

• Limit the contact window to the near future (up to 3 business days)
• Gauge the participants’ interest by the length of time before their scheduled appointment, and prioritize following up with those that are farther away.
  • Generally, those who are really interested in the trial will book a call as soon as possible and won’t need as much effort to contact them. Those who schedule for further out, need more attention and may have questions or concerns that have been left unanswered.
• Call to confirm as soon as you’re able to. If you catch them and they have time, you may be able to complete their phone screening sooner than anticipated, but even if you get their voicemail, you’ll make first contact with them. Your phone number will be more recognizable, and you can introduce yourself before your call.
  • Focusing on those who book their appointment further in the future will allow them to ask any questions or voice any concerns they may have.
• Don’t delay following up with them. You should be contacting them everyday or every other day using email, text messages, and additional phone calls until you’ve gotten a response or have reached at least 10 attempts.
  • If they reach out to your team via phone or email, be sure to respond as quickly as possible. Replying to their questions quickly will minimize concerns festering which could result in reduced retention.

• Have one point of contact for them to get to know, like, and trust. This person should be knowledgeable of the study, have a high emotional intelligence, and be able to catch ‘flags’ that may show signs of hesitancy. (see our Phone Screening Best Practices for more on identifying red flags)
• Send personalized reminders and include information they shared to increase their interest.
• Remind them of their motivation to join the study to establish your connection, and tailor your conversations to their own experiences. Trialfacts asks why they signed up for the trial during prescreening, their answers provide great insight you can use for this purpose.
• Use real-life examples of how participation could contribute to their community.
• Do not use a blocked or private number. US-based researchers should have a local number and Australia-based researchers should use a mobile number (beginning with 04)
• Ask for the participant’s preferred method of contact, and use it along with other contact methods to maximize their response rate.
• Make sure you always put your phone number in your email signature or your texts—this gives the person a way to contact you if they have any questions.
• Avoid using bulk sending services with opt-out messages at the bottom of your texts or emails, as these give the impression that you are contacting many people in bulk, and their individual participation means little.
• Make sure your text messages and emails sound like they’re coming from an actual person. Robotic-sounding messages do not inspire trust.
• Your study team should be aware of the symptoms and struggles of people living with the condition you’re researching. Having this knowledge can help them be empathetic and reassuring when discussing the study with them.
• Be personable! Make the participant as comfortable as possible. Being friendly and chatty gets them to let their guard down. Sharing information about yourself makes them feel less exposed.

• Persistence is key. If the volunteer does not pick up the phone when you call them at the designated time, be relentless in following up. Trialfacts suggests 10 contact attempts using multiple methods.
• If they do not answer the phone call, leave a voicemail and follow up with a personalized text message or email right away including your name and your reason for calling. If they still haven’t answered, leave one or at most two days before trying again. Keep calling until they have to pick up the phone.
• If the recruitment deadline is in less than a week, try once or twice a day.

Remember that it is very easy for volunteers to say they’re not interested, especially via text message. So don’t make the mistake of assuming your volunteers’ level of interest until they actually tell you they’re not interested, or until you’ve called them and left text message, emails, and/or voicemails at least ten times.