Transtheoretical individualized multimedia expert systems targeting adolescents' health behaviors

Transtheoretical individualized multimedia expert systems targeting adolescents' health behaviors

144 Transtheoretical Individualized Multimedia Expert Systems Targeting Adolescents' Health Behaviors Colleen A. R e d d i n g , J a m e s O. Prochas...

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Transtheoretical Individualized Multimedia Expert Systems Targeting Adolescents' Health Behaviors Colleen A. R e d d i n g , J a m e s O. Prochaska, U n t o E. P a l l o n e n , J o s e p h S. Rossi, Wayne E Velicer, Susan R. Rossi, Geoffrey W. G r e e n e , Kathryn S. Meier, Ker~ T E. Evers, Brett A. P l u m m e t , a n d J a s o n E. M a d d o c k , Cancer Prevention Research Center, University o f Rhode Island The transtheoretical model has advanced research and practice for many health behavior changes among adults, but few applications have been developed and applied among adolescents. This paper will describe an innovative and promising computer-based technology for standardized assessment and individualized theory-based intervention delivery called expert systems. Two different studies utilizing multimedia expert systems technologyfor assessing and intervening with adolescents targeting several health behaviors will be described. One study includes high school students and targets smoking cessation or prevention, sun protection, and dietarf fat reduction. The other study includes urban adolescentfemale clients recruited in family planning clinics and targets condom adoption and either smoking cessation or prevention. The advantages and disadvantages of expert systems technology are reviewed. Multimedia expert system technology has the potential to enhance health promotion and adherence by integrating the strongest components from both clinical and public health models of intervention.

HIS PAPERwill describe the development and application of current computer-based expert system intervention delivery systems being utilized and evaluated in different randomized clinical trials (RCT) targeting different adolescent populations. First, the transtheoretical model that provides the theoretical foundation for expert systems and these RCTs wilt be described. A description of expert systems in general and a rationale for utilizing these systems among adolescents, in particular, will be presented. Then, the studies that are using this technology will be described, as well as some of the contextual factors influencing expert systems use in different settings. Finally, some of the main strengths and weaknesses of expert systems as both research and clinical tools will be summarized.

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Transtheoretical M o d e l The past 20 years of transtheoretical model-based research has found some common principles of behavior change which have applied to a wide range of health behaviors. These behaviors include smoking cessation, exercise adoption, sun protection, dietary fat reduction, condom adoption, adherence to mammography screening, medication adherence, stress management, and substance abuse cessation, to name just a few (Prochaska & DiClemente, 1983, 1985; Prochaska, Norcross, Fowler, Follick, & Abrams, 1992; Prochaska, Redding, Harlow, Rossi, Cognitive and Behavioral Practice 6, 144-153, 1999 1077-7229/99/144-15351.00/0 Copyright © 1999 by Association for Advancement of Behavior Therapy. All rights of reproduction in any form reserved.

& Velicer, 1994; Prochaska & Velicer, 1997). These problem behaviors are important from a public health standpoint because they are strongly associated with both increased mortality and with decreased quality of life. The TTM is a model of intentional behavior change that has produced a large volume of research and service across a wide range of problem behaviors and populations (Prochaska & DiClemente, 1983, 1985; Prochaska et al., 1992, 1994; Prochaska & Velicer, 1997). This model describes the relationships among stages of change, processes of change, decisional balance or the pros and cons of change, situational confidence or self-efficacy in the behavior change, and situational temptations to relapse. Table 1 describes all the constructs that collectively comprise the TTM. This model has several advantages. First, it describes behavior change as a process as opposed to an event. Then, by breaking the change process down into stages and studying which variables are most strongly associated with progress through the stages, this model provides important tools for both research and intervention development. Across different problem behaviors and populations, different variables have been associated with stage movement for each stage of change (Prochaska, Velicer, Guadagnoli, Rossi, & DiClemente, 1991). These TTM findings inform the design of individualized stagematched expert system interventions that target those variables most predictive of progress for individuals at each stage of change. One aspect of this model that often goes unrecognized is that it is the processes of change that drive movement through the stages of change (Prochaska & DiClemente, 1984). Thus, although commonly referred to as the "Stages of Change Model,"

M u l t i m e d i a Expert S y s t e m s for A d o l e s c e n t s

Table 1 Transtheoretical Model Constructs Constructs (Abbreviation) Stages of Change Precontemplation (PC) Contemplation (C) Preparation (PR) Action (A) Maintenance (M) Decisional Balance Pros Cons Self-Efficacy Confidence Temptation

Description No intention to take action within the next 6 months Intends to take action within the next 6 months Intends to take action within the next 30 days and has taken some behavioral steps in this direction Has changed overt behavior for less than 6 months Has changed overt behavior for more than 6 months The benefits of changing The costs of changing Confidence that one can engage in the healthy behavior across different challenging situations Temptation to engage in the unhealthy behavior across different challenging situations

Processes of Change Consciousness Raising (CR)

Finding and learning new facts, ideas, and tips that support the healthy behavior change Experiencing the negative emotions (fern; anxiety, Dramatic Relief (DR) worry) that go along with unhealthy behavioral risks Environmental Reevaluation (ER) Realizing the negative impact of the unhealthy behavior or the positive impact of the healthy behavior on one's proximal social and/or physical environment Social Liberation (SO) Realizing that the social norms are changing in the direction of supporting the healthy behavior change Self-Reevaluation (SR) Realizing that the behavior change is an important part of one's identity as a person Substitution of healthier alternative behaviors and/or Counterconditioning (CC) thoughts for the unhealthy behavior Helping Relationships (HR) Seeking and using social support for the healthy behavior change Reinforcement Management (RM) Increasing the rewards for the positive behavior change and/or decreasing the rewards of the unhealthy behavior Stimulus Control (SC) Removing reminders or cues to engage in the unhealthy behavior and/or adding cues or reminders to engage in the healthy behavior Self-Liberation (SL) Making a firm commitment to change

since stage is t h e c o r e c o n s t r u c t a r o u n d w h i c h o t h e r m o d e l c o n s t r u c t s are o r g a n i z e d , this is a m i s n o m e r b e c a u s e it focuses a t t e n t i o n o n o n l y o n e c o n s t r u c t f r o m this m u l t i d i m e n s i o n a l m o d e l . Naturally, m o d e l - b a s e d i n t e r v e n t i o n s are m u l t i d i m e n s i o n a l as well. T T M res e a r c h has f o u n d r e m a r k a b l e similarities across d i f f e r e n t kinds o f b e h a v i o r c h a n g e s , We h a v e f o u n d r e p e a t e d l y t h a t the stages o f c h a n g e h a v e p r e d i c t a b l e r e l a t i o n s h i p s with the p r o s a n d cons o f b e h a v i o r c h a n g e , c o n f i d e n c e in b e h a v i o r c h a n g e , t e m p t a t i o n to relapse, a n d t h e processes Of c h a n g e .

Stages of Change Individuals d o n o t c h a n g e t h e i r b e h a v i o r all at o n c e ; they c h a n g e it i n c r e m e n t a l l y o r stepwise in stages o f

c h a n g e . T h e stages m o s t c o m m o n l y u s e d across r e s e a r c h areas i n c l u d e : p r e c o n t e m p l a t i o n , c o n t e m p l a t i o n , p r e p a ration, action, a n d m a i n t e n a n c e . Individuals d o n o t typically m o v e linearly f r o m stage to stage, b u t o f t e n p r o g r e s s a n d t h e n recycle b a c k to a p r e v i o u s stage b e f o r e m o v i n g f o r w a r d again. This c h a n g e p r o c e s s is c o n c e p t u a l i z e d m o s t m e a n i n g f u l l y as a spiral (see F i g u r e 1), w h i c h illustrates t h a t e v e n w h e n individuals d o recycle to a stage t h e y h a v e previously o c c u p i e d , t h e y m a y still have l e a r n e d from their previous experiences. Precontemplation d e s c r i b e s individuals w h o f o r m a n y r e a s o n s d o n o t i n t e n d to c h a n g e w i t h i n t h e n e x t 6 m o n t h s . S o m e o f t h e s e individuals m a y w a n t to c h a n g e at s o m e f u t u r e time, b u t j u s t n o t w i t h i n t h e n e x t 6 m o n t h s . O t h e r s m a y n o t w a n t to c h a n g e at all a n d , in fact, m a y b e

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Redding et al. tion, a l t h o u g h somewhat less t h a n for individuals in the action stage.

TERMINATION

PRECONTEMPLAT[ON

PRECONTEMPLATION CONTEMPLATION9REPANATION~ '*/

Figure 1. A hypothetical sequence of stages of change over time. very c o m m i t t e d to their p r o b l e m behavior (e.g., a lifel o n g s m o k e r o r s o m e o n e who regularly cultivates a d e e p tan). Contemplation describes individuals who are thinking a b o u t c h a n g i n g their p r o b l e m behavior within the n e x t 6 months. T h e y are m o r e o p e n to f e e d b a c k a n d information a b o u t the p r o b l e m b e h a v i o r than are their counterparts in the p r e c o n t e m p l a t i o n stage. Individuals in the preparation stage are c o m m i t t e d to c h a n g i n g their p r o b l e m behavior soon, usually within the n e x t 30 days. These p e o p l e have often tried to c h a n g e in the past a n d / o r have b e e n practicing c h a n g e efforts in small steps to h e l p t h e m get ready for their actual c h a n g e attempt. T h e action stage includes individuals who have c h a n g e d their p r o b l e m behavior within the past 6 months. T h e c h a n g e is still quite new a n d their risk for relapse is high, r e q u i r i n g their constant a t t e n t i o n a n d vigilance. Maintenance-stage individuals have c h a n g e d their p r o b l e m behavior for at least 6 months. T h e i r c h a n g e has b e c o m e m o r e o f a habit, a n d their risk for relapse is lower, b u t relapse p r e v e n t i o n still requires some atten-

Processes o f Change T h e processes o f c h a n g e describe the 10 cognitive, emotional, behavioral, a n d i n t e r p e r s o n a l strategies a n d techniques that individuals a n d / o r c h a n g e agents (therapists, counselors) use to c h a n g e p r o b l e m behaviors (Prochaska & DiClemente, 1983, 1985), Research has d e m o n s t r a t e d that successful behavior c h a n g e d e p e n d s u p o n the use o f the right processes at the right stage (Marcus, Rossi, Selby, Niaura, & Abrams, 1992; Prochaska, DiClemente, Velicer, & Rossi, 1993). TTM-based research has consistently f o u n d that different processes are used to progress to different stages. Thus, the processes mediate the transitions from stage to stage a n d can r e p r e s e n t i m p o r t a n t i n t e r m e d i a t e outcomes o f interventions (see Table 2). In fact, as some research areas a b a n d o n no-treatm e n t control groups in favor o f usual care o r m i n i m a l treatments, the processes o f c h a n g e provide o n e m e t h o d for assessing potential impacts o f s t a n d a r d care o r alternative t r e a t m e n t groups c o m p a r e d to the e x p e r i m e n t a l group. T h e processes o f c h a n g e are also ideal tools for process-to-outcome research a n d in m a n y ways provide the f o u n d a t i o n for e x p e r t system intervention design. Many studies across p r o b l e m behaviors (Prochaska, Velicer, DiClemente; & Fava, 1988;J. s. Rossi, 1992) have f o u n d that the 10 most used processes o f c h a n g e are organized into two h i g h e r - o r d e r clusters o f processes: the experiential processes (consciousness raising, d r a m a t i c relief, e n v i r o n m e n t a l reevaluation, social liberation, selfreevaluation) a n d the behavioral processes (counterconditioning, h e l p i n g relationships, r e i n f o r c e m e n t management, stimulus control, self-liberation). T h e experiential set o f processes are most often e m p h a s i z e d in earlier stages ( p r e c o n t e m p l a t i o n , c o n t e m p l a t i o n , a n d p r e p a r a tion) to increase i n t e n t i o n a n d motivation; the behavioral set o f processes are most often utilized in later stages (preparation, action, a n d m a i n t e n a n c e ) as observ-

Table 2 Processes of Change That Mediate Progress Between Stages of Change Precontemplation

Contemplation

Consciousness Raising Dramatic ReliefEnvironmental Reevaluation

Preparation

Action

Maintenance

t Self-Reevaluation - -

I Self-Liberation Helping Relationships Reinforcement Management Counterconditioning Stimulus Control

Note. Social Liberation was omitted due to its unclear relationship to the stages.

[ I I t

Multimedia Expert Systems for Adolescents able behavior change efforts get underway and need to be maintained. Decisional Balance

Decisional balance or the pros and cons of behavior change describe the importance or weight of an individual's reasons for changing or n o t changing. They relate strongly and predictably to the stages of change (Prochaska, 1994; Prochaska, Velicer, Rossi, et al., 1994). These are the decision-making c o m p o n e n t s o f the TTM and also serve as two important intervening or intermediate outcome variables. Individuals' decisions to move from one stage of change to the next are based on the relative weight given to the pros and cons of adopting the healthy behavior. The pros are the positive aspects of changing behavior or the benefits of change (reasons to change). In contrast, the cons include the negative aspects of changing behavior, or barriers to change (reasons not to change). These two dimensions have been consistently supported by studies across many different problem behaviors in TTM-based research (Prochaska, Velicer, Rossi, et al., 1994). A variety of studies across a wide range of problem behaviors have f o u n d that the pattern of comparative weighing of the pros and cons depends on the individual's stage o f change (Prochaska, 1994; Prochaska, Velicer, Rossi, et al., 1994). Characteristically, the pros of healthy behavior are low in the early stages and increase across the stages of change and the cons of the healthy behavior are high in the early stages and decrease across the stages of change. The pros and cons are particularly useful when intervening with individuals in early stages of change. Decisional balance is an excellent indicator o f an individual's decision to move out of the precontemplation stage. The relationship between the stages of change and decisional balance has been shown to be remarkably consistent across at least 12 different problem behaviors (Prochaska, Velicer, Rossi, et al., 1994). Not only has the relationship between stage and the pros and cons been replicated across problem behaviors, but the magnitude of the change across the stages of change has been replicated as well. Research has shown that in progressing from precontemplation to action, the pros of change generally increase by about one standard deviation, whereas the cons o f change tend to decrease by about one-half o f a standard deviation. Based on these data, the strong and weak principles of behavior change were formulated (Prochaska, 1994).

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maintenance described by Shiffman (1986). These variables have u n d e r g o n e considerable elaboration over time, with situational temptation to engage in the unhealthy behavior often viewed as an equally important c o m p a n i o n construct to the m o r e c o m m o n l y used situational confidence measures. Confidence and temptation function inversely across the stages, and temptation predicts relapse better. Research has demonstrated that both the confidence and temptation constructs can be conceptualized psychometrically as unifactorial a n d / o r multifactorial. Structural modeling analyses have repeatedly revealed a global higher-order construct (confidence or temptations) comprised of several lower-order situationally determined components (Clark, Abrams, Niaura, Eaton, & Rossi, 1991; Redding & Rossi, 1999; Velicer et al., 1990). The lower-order situational factors depend more strongly u p o n the problem behavior than the higherorder construct. A global score is often useful as a general screening tool, while the situational subscale scores provide useful information for targeting intervention feedback to individuals at different stages of change. Confidence and temptation both vary across the stages of change, with confidence rising and temptation decreasing across longitudinal profiles of smokers (Prochaska et al., 1991). A moderate, reciprocal relationship (r= - . 6 0 ) has been f o u n d between temptation and confidence for both smoking cessation and safer sex behaviors (Redding & Rossi, 1999; Velicer et al., 1990). Confidence is typically lowest in the precontemplation stage, since individuals have little performance feedback a n d / or little interest in change. Confidence is higher during contemplation, o u t p e r f o r m i n g demographic variables in its ability to predict m o v e m e n t into preparation and action stages (DiClemente et al., 1991). Even in the maintenance stage, where subjects have successfully altered the problem behavior for at least 6 months, temptation is o n e of the best predictors of relapse and recycling to earlier stages of change (Redding et al., 1989). Expert Systems

An expert system c o m p u t e r program mimics or codifies the reasoning of h u m a n experts. 1 The program uses standardized decision rules or algorithms for assessment and providing feedback and applies those algorithms consistently. An expert system utilizing the TTM is an integrated assessment and intervention delivery c o m p u t e r program (Pallonen, Velicer, et al., 1998; Velicer et al., 1993, 1999). This technology integrates audio computer-

Situational C o n f i d e n c e and Temptations

The serf-efficacy construct utilized in the TTM (DiClemente, 1986; Velicer, DiClemente, Rossi, & Prochaska, 1990) integrates the models of serf-efficacy proposed by Bandura (1986) and the coping models of relapse and

1By definition, true expert systems continue to learn or develop algorithms as they work and therefore they change over time. This is one feature of expert systems that is notutilized in our expert systems, since scientific rigor requires intervention delivery systems that are stable during the course of a study.

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Redding et al. assisted self-interviewing technology (audio CASI; Bloom, 1998; Gustafson, Bosworth, Chewning, & Hawkins, 1994; T u r n e r et al., 1998) with systematic theory-based intervention feedback. T h e r e are currently two types o f stage-matched e x p e r t systems: batch a n d multimedia. Batch systems reflect the e x p e r i e n c e o f the r e s p o n d e n t who completes survey items, either by a mail o r p h o n e survey, a n d submits t h e m for off-site (batch) processing. T h e r e s p o n d e n t t h e n receives a stage-matched individualized intervention feedback r e p o r t t h r o u g h the mail within a week or so. Batch systems have b e e n used primarily with various a d u l t populations a n d have b e e n f o u n d to be effective for smoking cessation (Prochaska et al., 1993; Prochaska et al., 1998a, 1998b; Velicer, Prochaska, Fava, Laforge, & Rossi, 1999), sun p r o t e c t i o n (J. S. Rossi, Weinstock, Redding, Cottrill, & Maddock, 1997; Weinstock, Rossi, Redding, & Maddock, 1998), dietary fat r e d u c t i o n ( G r e e n e et al., 1998a), a n d m a m m o g r a p h y screening (Rakowski et al., 1998). M u l t i m e d i a interactive e x p e r t systems, in contrast, provide m o r e i m m e d i a t e f e e d b a c k to the r e s p o n d e n t , who sits at the c o m p u t e r a n d completes a series o f questions followed by feedback. Participants r e s p o n d to several series o f questions i n t e r s p e r s e d with f e e d b a c k on diff e r e n t TTM constructs (see Table 3). These systems have b e e n d e v e l o p e d m o r e recently a n d have b e e n used primarily with adolescents. T h e m u l t i m e d i a intervention delivery systems d e s c r i b e d h e r e were d e v e l o p e d to be feasible in different settings. Ease of use was vital, so that even users without p r i o r c o m p u t e r e x p e r i e n c e could use t h e m (e.g., like an a u t o m a t e d teller m a c h i n e ) . Users only n e e d to use a mouse to p o i n t at a n d click on their response to an on-screen question, so no keyboard typing is necessary. These systems provide b o t h normative f e e d b a c k (i.e., c o m p a r e s responses o f an individual to a normative database o f same-stage peers who have m a d e progress) a n d ipsative f e e d b a c k (compares c u r r e n t responses of an individual to his o r h e r previous responses). These feed-

back types are described elsewhere (Pallonen, Velicer, et al., 1998; Velicer et al., 1993; Velicer et al., 1999). Positive o r negative f e e d b a c k is then p r e s e n t e d to tile particip a n t d e p e n d i n g on the comparison. This allows even first-time users o f the system to get i m p o r t a n t a n d helpful f e e d b a c k on key variables associated with behavior change. At follow-up intervention points, the system provides ipsative f e e d b a c k (i.e., c o m p a r i s o n between an individual's responses now to same ones previously). Thus, positive a n d negative f e e d b a c k on the individual's own c h a n g e over time is an i m p o r t a n t feature o f these systems. This type o f f e e d b a c k derives from clinical m o d e l s o f intervention. Again, the specific variables targeted for each stage are those most associated with stage progression for that stage. Tailoring Figure 2 describes the level o f individualization that is currently i m p l e m e n t e d within e x p e r t system interventions. Tailoring has b e c o m e a p o p u l a r term in the science of intervention development. However, what is m e a n t by tailoring varies substantially. This graphic shows diff e r e n t levels of tailoring possible with different types o f interventions. F o r example, at the g r o u p level m i g h t be an informational p a m p h l e t o r "one-size-fits-all" intervention (which has historically b e e n action-oriented). At the n e x t level, an intervention could consist o f 5 stage-tailored manuals, that is, p a m p h l e t s a p p r o p r i a t e for individuals in each o f the 5 stages o f c h a n g e (e.g., Marcus et al., 1998). At the next level, one may still g r o u p p e o p l e by stage, b u t give even m o r e t a r g e t e d f e e d b a c k on some c o n t i n u o u s variable, for example, self-efficacy, (Campbell et al., 1994; Skinner, Strecher, & Hospers, 1994). At the final level, the level of the c u r r e n t e x p e r t systems, individuals are n o t only g r o u p e d on relevant variables (e.g., stages o f change), b u t receive targeted positive o r negative, nor-

Table 3

Multimedia Expert System Sections by Target Behavior Expert System Section Introduction Stage & Behavior* Pros & Cons* Confidence* Temptations* Processes of Change* Strategies Summary

Smoking Cessation/ Prevention

Low-Fat Eating Habits

~ ~ ~

~ tt t,,"

~ v" ~ v"

v," t,~ ~

Sun Protection

Condom Adoption

~ tl ~ ~

t~ ~,~

vl ~,' v,"

v~" ~, v,"

* Includes a series of questions followed by stage-matched, individualized feedback.

.v,"

Multimedia Expert Systems for A d o l e s c e n t s

Precontemplation

Contemplation

Preparation

Action

149

Maintenance

Figure 2. Levels of tailoring by different types of interventions.

mative ( c o m p a r e d to peers) a n d ipsative ( c o m p a r e d to self before) f e e d b a c k on all relevant variables associated with c h a n g e (e.g., Prochaska, DiClemente, et al., 1993; Velicer et al., 1993; Veticer et al., 1999). This figure illustrates j u s t how highly tailored a n d individualized e x p e r t system f e e d b a c k is. This figure also suggests some important research questions r e g a r d i n g the d e g r e e o f tailoring necessary for b e h a v i o r change interventions to be b o t h effective a n d cost-efficient. Adolescence

A d o l e s c e n c e is a time o f transition from c h i l d h o o d to increasing i n d e p e n d e n c e for m a n y y o u n g p e o p l e , often i n c l u d i n g e x p e r i m e n t a t i o n with various lifestyle a n d behavioral choices. These choices can place t h e m at risk for m a n y h e a l t h a n d social p r o b l e m s (Dryfoos, 1991). Lifestyle behaviors a n d habits a d o p t e d d u r i n g a d o l e s c e n c e may linger well into a d u h h o o d . Thus, these behaviors n o t only place t h e m at c u r r e n t risk, b u t strongly influence their future risks as well. This time o f transition, then, presents an i m p o r t a n t o p p o r t u n i t y for interventions a i m e d at h e l p i n g y o u n g p e o p l e choose healthy alternatives or protect themselves from potentially harmful ones. F u r t h e r m o r e , adolescents have strong d e v e l o p m e n t a l concerns with i n d e p e n d e n c e a n d self-determination. These c o n c e r n s can m a k e a c t i o n - o r i e n t e d interventions feel particularly coercive to adolescents who are n o t yet ready to change. For c o m p a r a b l e reasons, these developm e n t a l c o n c e r n s make TTM intervention principles ideally suited to adolescents' i n t e r v e n t i o n needs. Some TTM i n t e r v e n t i o n principles include:

• respect the individual's readiness to change; • ask participants to d o only what it takes to progress to the n e x t stage; • b u i l d on an individual's strengths b e f o r e p r o v i d i n g corrective feedback; • b u i l d on self-help strategies a n d options before reco m m e n d i n g a d d i t i o n a l sources of help; • s u p p o r t the individual's decision-making capability; • s u p p o r t the individual's choice o f when a n d how to change. Finally, adolescents can also e x p e r i e n c e h e i g h t e n e d sensitivity to the d e m a n d characteristics o f interviews o r surveys, especially in sensitive topic areas (e.g., sex). Stand a r d i z e d c o m p u t e r assessments can minimize these dem a n d characteristics, providing o p p o r t u n i t i e s for m o r e accurate r e s p o n d i n g (Bloom, 1998; T u r n e r et al., 1998). This p a p e r describes work with two different a n d important a d o l e s c e n t populations: (1) male a n d female 9thgrade high School students a n d (2) 14- to 17-year-old u r b a n female family-planning clinic clients. Both of these different a d o l e s c e n t p o p u l a t i o n s e n c o m p a s s a wide cont i n u u m o f behavioral risks for different p r o b l e m behaviors. T h e p a p e r will only focus o n the behaviors that have b e e n a d d r e s s e d in o u r c u r r e n t collaborative research a m o n g adolescents: • • • •

smoking cessation ( a m o n g smokers) smoking p r e v e n t i o n ( a m o n g n o n s m o k e r s ) c o n d o m use sun protective behaviors • low-fat eating habits.

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Redding et al. Table 3 describes all the sections in the adolescent exp e r t systems. These sections c o r r e s p o n d closely to those also reviewed in Velicer a n d colleagues (1993; Velicer et al., 1999). T h e i n t r o d u c t i o n , strategies, a n d s u m m a r y sections contain no questions. Each section presents differe n t b a c k g r o u n d pictures r e l a t e d to the target behavior. T h e sections that include q u e s t i o n s / r e s p o n s e s / f e e d b a c k (see asterisks in Table 3) share the same screen layout, with different b a c k g r o u n d pictures. Table 3 also illustrates how m u c h system structure is c o m p a r a b l e across behaviors. C u r r e n t m u l t i m e d i a systems either use confid e n c e ( c o n d o m use a n d sun p r o t e c t i o n ) o r temptations (smoking a n d low-fat eating habits), b u t n o t b o t h so that response b u r d e n is m i n i m i z e d for participants. M u l t i m e d i a c o m p o n e n t s were i n t e g r a t e d into these systems to m a k e adolescents' c o m p u t e r interactions m o r e captivating a n d to h i g h l i g h t i m p o r t a n t intervention feedback. T h e f e e d b a c k text was written at a 6th-grade r e a d i n g level so that it would be accessible, even for less skilled readers. T h e same f e e d b a c k is p r e s e n t e d in two ways simultaneously: as text viewed on a screen a n d r e a d t h r o u g h a u d i o e a r p h o n e s . This allows the f e e d b a c k to rem a i n confidential, b u t capitalizes o n the fact that auditory c o m p r e h e n s i o n exceeds r e a d i n g c o m p r e h e n s i o n for most individuals. Also, this feature allows individuals with different l e a r n i n g styles to benefit from either the visual p r e s e n t a t i o n o f text on-screen o r the auditory f e e d b a c k p r e s e n t e d t h r o u g h e a r p h o n e s . Thirty to 60 seconds o f p o p u l a r music was also i n c l u d e d at b o t h the i n t r o d u c t i o n a n d conclusion o f each p r o g r a m .

School-Based Study H e a l t h I n f o r m a t i o n Highway" is the n a m e o f the R h o d e Island h i g h s c h o o l - b a s e d p r o j e c t that uses b o t h e x p e r t systems a n d c o m p l e m e n t a r y c u r r i c u l u m c o m p o nents to d e c r e a s e smoking, increase sun-protective behaviors, a n d d e c r e a s e dietary fat c o n s u m p t i o n a m o n g h i g h school students (Prochaska, Pallonen, et al., 1994; Pallonen, 1998). At baseline, N = 4,983 n i n t h g r a d e r s were e n r o l l e d who were followed t h r o u g h o u t the 2-year i n t e r v e n t i o n p e r i o d a n d for 2 years afterward. O u r participation rates were h i g h at 90% (Prochaska, Pallonen, et al., 1994). T h e first step toward d e v e l o p i n g e x p e r t systems for these adolescents (Velicer et al., 1999) was to verify t h e p s y c h o m e t r i c a n d n o r m a t i v e d a t a for s m o k i n g (Pallonen, 1998; Pallonen, Prochaska, R e d d i n g , et al., 1998; Plummer, Velicer, Pallonen, & Prochaska, 1998a), dietary fat (Benisovich et al., 1998; G r e e n e , 1998b; Plummer, Velicer, Pallonen, & Prochaska, 1998b; S. R. Rossi et al., 1998) a n d sun p r o t e c t i o n ( M a d d o c k et al., 1998). Formative r e s e a r c h f o u n d that the teenagers liked using the c o m p u t e r s , f o u n d the p r o g r a m s interesting, a n d would use c o m p u t e r - b a s e d i n t e r v e n t i o n s in t h e i r classrooms.

T h e most obvious a n d i m p o r t a n t aspects o f working in a school setting are the p r i m a r y educational mission a n d the fact that schools serve b o t h students as well as their parents. T h e fact that the interventions fit well into the existing curricula e n a b l e d the schools to be ready to inc o r p o r a t e e x p e r t systems targeting smoking, sun protection, a n d dietary fat reduction. In contrast, schools were n o t ready to c o n s i d e r i n c o r p o r a t i n g interventions targeting c o n d o m use o r alcohol use at this time. T h e e x p e r t systems were delivered to participants d u r i n g r e g u l a r h e a l t h e d u c a t i o n classes, m e a n i n g that they h a d to fit into a 40- to 50-minute class period. Since each behavior in the e x p e r t system takes 10 to 15 minutes to complete, students could only c o m p l e t e two out o f the t h r e e behaviors at each session. Also, c u r r i c u l u m c o m p o n e n t s were d e v e l o p e d to a d d to existing h e a l t h e d u c a t i o n classes as part o f the intervention. Family Planning Clinic-Based Study Step by Step: S t e p p i n ' for H e a l t h i e r Teens is the n a m e o f the P h i l a d e l p h i a project that uses b o t h stage-matched e x p e r t systems a n d stage-matched counseling components to increase c o n d o m use a n d decrease smoking a m o n g female 14- to 17-year-old clients (Prochaska, Redding, et al., 1993; Prochaska, Redding, & Evers, 1997). T h e project aims to decrease risks for cervical c a n c e r a m o n g at-risk female adolescents. At baseline, N = 833 n o n p r e g n a n t female adolescents e n r o l l e d who were followed t h r o u g h o u t the 9-month intervention p e r i o d a n d the 18-month project p e r i o d ( R e d d i n g et al., 1998). O f teens who m e t eligibility criteria, a b o u t 75% a g r e e d to participate in the study. Again, the first step toward develo p i n g e x p e r t systems for these adolescents was to verify the psychometric a n d normative data for b o t h smoking a n d c o n d o m use (Pallonen, Prochaska, Redding, et al., 1998; R e d d i n g et al., 1996a, 1996b, 1998). Again, formative research f o u n d that these teenagers liked using the computers, f o u n d the intervention p r o g r a m s useful a n d interesting, a n d would use c o m p u t e r - b a s e d interventions in family p l a n n i n g clinic settings (Prochaska, Redding, & Evers, 1997). In contrast to the school setting, the family p l a n n i n g clinic settings already saw reproductive h e a l t h as p a r t o f their public health mission, so they were ready to imp l e m e n t the c o n d o m - u s e e x p e r t system. In contrast, they were less ready to a c c e p t the smoking e x p e r t system as an i m p o r t a n t c o m p o n e n t of a w o m e n ' s h e a l t h intervention. As a consequence, we p r o v i d e d m o r e i n f o r m a t i o n a l s u p p o r t for the smoking systems in this setting. Family p l a n n i n g teenagers already saw a c o u n s e l o r as a r o u t i n e p a r t o f their visit, so in this study the t r e a t m e n t g r o u p also i n c l u d e d t r a i n e d stage-matched counselors, while the control g r o u p received usual care contraceptive counseling.

Multimedia Expert Systems for Adolescents

Discussion Two studies a m o n g adolescents illustrate the advantages of using expert systems interventions. They provide highly individualized and confidential feedback, appropriate for adolescents at all stages of readiness to change, not only those who are ready. They are potentially costeffective, even while integrating multiple risk behaviors and multimedia components. Their content can be updated and extended and new response modalities (e.g., voice recognition) or new empirical findings can be added. They have tremendous potential for dissemination (e.g., www/internet, health clinics, worksites, community centers, prisons, etc.). Expert systems can be used broadly as population-based treatments, stepping up care as necessary for those who require more intensive or costly interventions (Abrams et al., 1996). Finally, through all these means, they have great potential to increase public health impact on and primary prevention of important problem behaviors. O n e o f the biggest disadvantages of expert systems is that they do require highly explicit data-based decisionmaking rules and computational algorithms to be prog r a m m e d into the computer. Thus, cross-sectional and longitudinal databases are n e e d e d to inform decision making rules and to provide a basis for normative and ipsative comparisons. Initial development o f expert system technology requires costly c o m p u t e r hardware and software, as well as extensive technical expertise, which can be barriers. O n c e a system is developed, however, the costs of adapting and updating it for a new setting or sample are significantly lower. Multimedia c o m p o n e n t s were integrated into expert systems because we believed that they would increase attention and c o m p r e h e n s i o n of the main feedback points. However, additional research is n e e d e d to better evaluate how m u c h of any particular c o m p o n e n t enhances the efficacy of existing programs. Given this early state of the art and science, many j u d g m e n t s about multimedia components were quite subjective. This is in sharp contrast to our j u d g m e n t s about the stage-matched components, which were highly informed by both theory and data. In practice, there may be inherent limits to the responsiveness, warmth, a n d empathy of a computerdelivered intervention, c o m p a r e d to clinicians. However, it remains unclear where those limits may be. No matter how many "bells and whistles" are incorporated into expert systems, they can still only respond in the ways that they have been programmed. This point reflects both a strength and a weakness o f expert systems in practice. As a strength, the intervention is delivered in the same way with all individuals meeting the same criteria (a.k.a., fidelity). As a weakness, the program c a n n o t shift to another problem quickly or respond to potentially impor-

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tant cues (e.g., laughter or tears) aside from those that are directly input. With problem behaviors or populations that d e m a n d more personal responsiveness, warmth, or clinical attunement, counselors a n d / o r clinicians can be a d d e d to intervention protocols. In the family planning clinic-based project already described, stage-matched counselors were an important c o m p o n e n t o f the intervention package. In fact, the expert system in that study p r o d u c e d stage-matched feedback, for both the participant and her counselor, that was used to guide the sessions. In this way, costly expertise can be utilized m o r e efficiently. Thus, even in settings or populations where computers cannot provide all the necessary ingredients for a successful intervention, they can provide many if not most o f those ingredients. In summary, we are very excited about this novel and innovative assessment and intervention delivery system, especially for adolescents. We believe the benefits o f expert systems far outweigh their disadvantages, both for our research group and for the fields of intervention science and, more broadly, public health. We look forward to developing and applying this technology in additional behavioral areas important a m o n g adolescents, for example drinking (Migneault, Pallonen, & Velicer, 1997) and exercise (Nigg & Courneya, 1998). Future systems may help to m e e t secondary prevention goals in medical settings, such as helping adolescents u n d e r g o i n g medical treatment (Ruggiero, 1998). Furthermore, these systems integrate the best theory and data to date for intervening with individuals (the clinical model), as well as the best evidence for intervening with populations (the public health model). This integration retains some of the efficacy o f clinical models, while retaining some of the reach from public health models, thus greatly increasing the population impact of the intervention (Abrams et al., 1996; Prochaska, 1996; Prochaska & Velicer, 1997; Velicer & DiClemente, 1993; Velicer & Prochaska, 1999). Utilizing expert systems in additional settings and samples are n e e d e d to provide m o r e information about their generalizability. Furthermore, efficacy data on these systems are n e e d e d to direct the further development of the next generation of stage-matched expert system interventions.

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Velicer, W. E, & DiClemente, C. C. (1993). Understanding and intervening with the total population of smokers. Tobacco Control, 2, 95-96. Velicer, W. E, DiClemente, C. C., Rossi, J. S., & Prochaska, J. O. (1990). Relapse situations and self-efficacy. Addictive Behaviors, 15, 271-283. Velicer, W. E, & Prochaska, J. O. (1999). An expert system intervention for smoking cessation. Patient Education and Counseling, 36, 119129. Velicei, W. E, Prochaska,J. O., Bellis,J. M., DiClemente, C. C., Rossi,J. S., Fava, J. L., & Steiger, J. H. (1993). An expert system intervention for smoking cessation. Addictive Behaviors, 18, 269-290. Velicer, W. E, Prochaska, J. O., Fava, J. L., Laforge, R. G., & Rossi,J. S. (1999). Interactive versus non-interactive interventions and doseresponse relationships for stage-matched smoking cessation programs in a managed care setting. Health Psychology, 18, 21-28. Velicer, W. E, Prochaska,J. O., Fava, J. L., Norman, G.J., & Redding, C. A. (1998). Smoking and stress: Applications of the transtheoretical model of behavior change. Homeostasis, 38, 216-233. Weinstock, M. A., Rossi, J. S, Redding, C. A., & Maddock, J. E. (1998). Randomized trial of intervention for sun protection among beachgoers. Journal of Investigative Dermatology, 110, 589 (Abstract). This research was partially supported by Grants #C&50087, #CA63745, #CA27821 (RI.-J.O. Prochaska) from the National Cancer Institute and an Administrative Supplement from the Office of Women's Health to C. A. Redding. Portions of this article were presented at the annual meeting of the Association for Advancement of Behavior Thet-apy in Atlanta, GA, November 1997, and the Society of Behavioral Medicine in New Orleans, LA, March 1998. Authors also wish to gratefully acknowledge all the input from our various collaborators and participants on projects, as well as the assistance and expertise in tile areas of systems development and programming (Guy Natelli) and multimedia components (David Masher). Address correspondence to Colleen A. Redding, Ph.D., Cancer Prevention Research Center, 2 Chafee Rd., University of Rhode Island, Kingston, RI 02881; e-mail: [email protected]

Received: June 11, 1998 Accepted: October 22, 1998

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