Tips en guidelines for writing informative recruitment letters

Aim

Better information letters to recruit participants

Description

Recruiting research participants is often difficult and the number of people wanting to participate can be disappointing.  A proper, attractive and clearly presented information package may help convince people to participate in your study.
These recommendations discuss a number of points:

- The typical behaviour of someone receiving an information package;
- The envelope;
- The response options;
- A letter with an example of a modified information letter provided by a VU University Medical Center (VUmc) Communication Advisor; 
- The brochure.

Just to be absolutely clear: For any research falling under the Medical Research Act (WMO), your brochure and information letter need to have been approved by the Medical Ethics Research Committee (Medisch Ethische Toetsingscommissie, METc). Once approved, the brochure and letter cannot be altered without consent from the METc.

Typical behaviour on receiving an information package
1. The recipient looks at the envelope and sees who has sent it. Based on this he will decide: Shall I open the envelope and have a look? Or shall I just throw it away unread?
2. After taking a quick glance at the letter and perhaps the brochure included, his attention will start to turn to the response options, such as a reply card. Clearly, that is where he expects to finds a brief summary of what is involved. He wants to get an idea of what the consequences are if he reads any further.
3. Is the response option clear? Will the topic scare him off, or will it have the opposite effect and interest him? The recipient will then have a look at the letter and read it in more detail. Will he discover an extensive description of the topic that will capture his imagination? If so, he will read through the sections fairly intensively.
4. Has a brochure been included? The recipient will normally find a comprehensive description of the topic here, along with illustrations and sufficient or more extensive background information.
5. Finally, the reader will return to the response options. He will carefully read through the topic again and will re-examine what he needs to fill out. He will complete it in full and put it aside for posting. 

Information packages such as these (referred to as direct mail in the business world) have a strong focus on obtaining a response from the reader. The package received by the potential research participant should be viewed as the first example of the professionalism with which you approach the study. And this therefore also involves the look!

The envelope
1. Address
Make clear that it is personally addressed to the recipient, preferably by name. Make sure the labelling is tidy (not skewed, which gives the impression of haste and a lack of care). A good quality envelope, clear sender’s details and a carefully completed, personal address are all required. 
2. Logo
Use the VU University Medical Center’s house style: This is an important recognition point for the recipients of the letter. Furthermore, recipients, in general, are more likely to open letters from organisations they are linked to, from whom they have requested information or - as is the case for the VUmc - organisations with a good reputation

The response options
The response option is there to lead the recipient to the real contents of the mailing. The options usually consist of:

• Requesting more information
• Registering (agreeing to participate in the study)

The most common form of response option is the response form or reply card, preferably provided with a pre-printed response envelope.

Elements of a response form;

• Subject: Subject of the mailing. Can generate interest.
• Response options: Indicate the way in which potential research participants can reply.
• Researcher’s obligations: Indicate what you will do in response to receiving the form.
• Expectations: Describe what the potential research participant can expect and what he/she is agreeing to undertake by returning the card.
• Details of potential researcher participant: Enable the researcher to respond to the reader.
• Researcher’s details: Describe exactly who the researcher is, so no misunderstandings can arise because of this.
• Address: Provide address details where the potential research participant sends the letter.

Tips:

• Ensure that the potential research participant has only to complete a minimum number of fields themselves (for instance, create tick boxes the recipient can select, offering a response option at the same time). This guides completion in columns, encouraging full completion.
• Avoid open questions.
• Don’t use the construction “Delete what is not applicable”. Instead, create a question that can be answered “yes” or “no” with tick boxes. This organises the form and makes it easier for the reader.
• Tick boxes also facilitate the processing of the response letter.
• Date a time when you will contact the potential research participant again (i.e. we will contact you by telephone within two weeks to make an appointment).
• Make sure there is enough space to fill in details.
• Make it as easy as possible for the potential research participant to reply. Freepost is best, but enclosing an envelope (with postage) or stamp increases the likelihood of a response.

The letter
Creating a recruitment letter using the AIDA formula (Attention, Interest, Desire, Action)

1. Introduction: Grab attention
The start of the letter has to grab the attention, just like the subject line and the PS option at the bottom of a letter.

2. Middle section: Creating interest and attention
What is the need for the research? How many people are involved in the subject you are studying? For instance, how many people in the reader’s neighbourhood could have that specific disorder?

3. Show potential research participants the importance and utility of the research to encourage them to participate.

4. Ending: Impulse to spur into action

• Tell the reader exactly what he needs to do
• Tell the reader how he needs to do this
• Make participation easy for the reader, or make it sound easy

Tips:

• A letter should never be more than two sides.
• Don’t use double-sided printing, as this looks less professional.
• Refer in the letter to the response option and any potential other documents/brochures.
• Use personal pronouns (address the reader as "you”, rather than using “one”, for instance).
• Use passive phrases as little as possible, and use active language (for instance, don’t say “The urine sample can be dropped off”, but rather say “You should drop off the urine sample”).
• Link in as much as possible to the potential research participant’s daily life. There are a number of emotional needs that may be applicable to the recipient of the letter regarding participation in a scientific study:
• Not having to go to any trouble or make any effort
• Becoming healthier
• Satisfying curiosity
• Protecting the family

Example
An example of a letter (in Dutch) modified by a Communication Advisor showing the differences in comparison with the original. The original was good, but could do more to attract participants.

The brochure
Is there too little space on the letter to include all the information?
Provide the potential research participant with more detailed information about the subject in a brochure. The brochure will include the particulars, show the topic (image) and provide a more detailed description. A good brochure will encourage the potential research participant to respond to the letter.

The information package will form a collection containing the letter, brochure and response options all tailored to each other. Layout, colours and contents should all be properly co-ordinated.

Improved information letter (Dutch)

V1.1: 1 Jan 2010 English translation
V1.0: 16  Dec 2005.