Interventions to Increase Cancer Screening by Increasing Client Demand

Research Gaps

What are Research Gaps?

Prior to and during the literature review and data analysis, the review team and the Community Preventive Services Task Force attempt to address the key questions of what interventions work, for whom, under what conditions, and at what cost. Lack of sufficient information often leaves one or more of these questions unanswered. The Community Guide refers to these as "research gaps." Research gaps can be pulled together in the form of a basic set of questions to inform a research agenda for those in the field.

Identified Research Gaps

For the six intervention approaches, the team identified key research issues that had not been answered in the review. Researchers are encouraged to consider which of these questions might be answered as part of studies already underway, through studies being planned, or through new studies. Research questions are grouped within each of the two effectiveness ratings (i.e., effective based on strong or sufficient evidence or undetermined based on insufficient evidence).

Interventions Shown to Be Effective

Additional evidence of effectiveness was found in these reviews, which demonstrated that three interventions to enhance community demand for breast, cervical, and colorectal cancer screening—client reminders, small media, and one-one-one education—are effective (strong or sufficient evidence) in increasing screening rates for one or more of these cancer sites. However, several important general and specific questions about effectiveness remain.

General:

• How does the effectiveness of interventions to increase community demand for screening vary with the health literacy of a target population or subpopulation?
• How can newer methods of communication—including automated telephone calls and Internet-delivered applications—be used to improve delivery, acceptance, and effectiveness of these interventions?
• How effective are these interventions in increasing screening by colorectal endoscopy or by double contrast barium enema (for which no qualifying studies were identified)?
• What is required to disseminate and implement effective interventions in community settings across the United States?
• How can or should these approaches be applied to assure that screening, once initiated, is maintained at recommended intervals?
• With respect to interventions that may be tailored to individuals, how are effective tailoring programs adapted, disseminated, and implemented in community-based settings across the United States?

Client reminders

(effective in increasing breast, cervical, and colorectal [FOBT only] cancer screening):

• Does effectiveness of client reminders for cervical and colorectal cancer screening vary with use of supplemental components, such as follow-up printed materials, telephone calls, or scheduling assistance intended to overcome barriers to screening?
• Can client reminders be adapted or used in conjunction with techniques to reach people who have never been screened for breast, cervical, or colorectal cancer or who may be hard to reach for screening?
• What is the comparative cost effectiveness of tailored versus untailored client reminder messages?

Small media

(effective in increasing breast, cervical and colorectal [FOBT only] cancer screening):

• Does effectiveness of small media differ by choice of medium (e.g., letter, video, brochure, or Internet-delivered application), information source (e.g., personal physician, educator), or intensity or frequency of delivery?
• What is the relative cost effectiveness of tailored versus untailored messages?

One-on-one education

(effective in increasing breast and cervical cancer screening only):

• What are the minimal and optimal duration, dose, and intensity requirements for one-on-one educational approaches to be effective?

Interventions for Which Effectiveness Is Undetermined

Effectiveness of client incentives (alone), mass media (alone), and group education has not been established for breast, cervical, or colorectal cancer screening. Remaining research questions in these areas include the following:

• Are these interventions potentially effective in increasing screening of these cancer sites?
• Are some incentives (e.g., ones of greater cash value or of greater appeal) more effective than others?
• Do these interventions result in other positive or negative changes in healthcare services (e.g., blood pressure monitoring or adult immunization) or health behaviors (e.g., smoking or physical activity)?
• Could incentives become a barrier to developing routine recommended screening practices or reducing patient autonomy in decision making?

Mass Media

Given the inherent expense of mass media interventions and costs already expended in efforts to answer remaining questions, it may be prudent to seek answers in lessons gleaned from studies of other health topics. What separate effects, if any, do mass media and other major components contribute to overall effectiveness of multicomponent media approaches to increase screening for breast, cervical, and colorectal cancers?

• What are the minimal and optimal component duration, dose, and intensity requirements for these approaches to be effective?
• Does effectiveness differ by mass media channel (e.g., TV, radio, billboard) for a given population or setting?
• What combinations of mass media and other interventions are optimal to increase a given cancer screening behavior or to reach particular target groups, such as low-income, ethnic, or minority populations?

Group Education

It has been difficult to generalize about the effectiveness of group education because of the variety of groups, settings, educators, and styles. Yet despite insufficient evidence of overall effectiveness, group education could be effective among selected subsets of the population, in certain settings, or under certain conditions. Thus, we encourage researchers to address additional basic questions that carefully examine specific elements of group education and target populations. We also encourage voluntary health organizations and public health agencies that remain committed to group education to collect additional evaluation data, where possible, to assess such programs as practiced.

• Is group education more effective in some settings than in others or when delivered in particular formats or by particular kinds of educators?
• Do some populations benefit more from group education than from other interventions?
• What are the minimal and optimal number, length, and intensity of group education sessions for intervention effectiveness and how does effectiveness vary by screening site and screening histories of populations?
• Are there optimal combinations of information and motivational content within group education interventions?
• Is group education effective when combined with other interventions, such as one-on-one education?
• What is the cost effectiveness of group education?