This column will give you practical ideas to improve your ROI (return on investment) in marketing medical meetings. My first article (and several to follow) focuses on successful direct marketing methods, because most marketing of medical meetings is, appropriately, direct marketing--and most direct marketing is direct mail.

So, How Many? The number of pieces you need to mail to achieve a given level of response is a function of a number of variables--the offer, the signatory, and the audience being principal among them. Generally, a one percent response is considered successful in the direct-mail business. A practical way to determine the quantity needed for a major campaign is to run a small-scale test. This is easier-- and more important--when dealing with larger markets. There's not much point in testing a mailing to all 1,100 allergists unless your promotion is very expensive. On the other hand, if you're planning on mailing to family practitioners, general practitioners, internal medicine specialists, and doctors of osteopathy, it is well worth the time and trouble to mail to a sample of 5,000 to determine if and how well your mailing will work.

A second question often raised is frequency. It does make great sense to mail multiple waves of a campaign for many of the same reasons it makes sense to run a series of space ads rather than one insertion. You can't count on the doctor opening one piece of mail. The day it arrives may be the day the doctor tosses all the direct mail--or the day before she has a need for your product or service.

A 250 Percent Increase We are fortunate that there is a wealth of information available documenting what marketing techniques work. The principles we'll discuss are drawn from what is known as the bible of direct marketing: Successful Direct Marketing Methods, by Bob Stone.

Bob Stone is in the Hall of Fame--the Direct Marketing Hall of Fame, that is. An adjunct professor at Northwestern University, his agency, Stone & Adler, ran many successful campaigns, one of which was conducted on behalf of your humble columnist. In the 1980s, they increased response to the American Medical Association's membership recruitment mailing campaign by 250 percent. So, the gospel according to Stone can can indeed work direct-marketing miracles.

Stone has identified six big keys to direct-marketing success--the Right Stuff, if you will. For example, one of the keys is The Right Media. Today, there are more choices than ever before. Will you rely completely on direct mail? Or will you use new media such as e-mail and broadcast fax, or even old media such as journal advertising, telemarketing, or personal sales?

The answer, in my opinion, is "all of the above." You should avoid putting all of your eggs in one basket for at least three reasons.

Audience receptivity: Some physicians may not read journals for months but they may go through the rest of the mail every day. Some have e-mail addresses and check their mailbox daily, others don't.

Synergy: A physician who reads about a CME opportunity in a journal ad and again in a direct mail piece may be more likely to recall the message.

Relative strengths: Journal ads are relatively inexpensive and can capture a physician's attention at a time when he or she is in a decision-making mode. A direct-mail piece can include a wealth of information and even useful objects, and is a powerful tool to generate responses.