Review of Computer-generated Outpatient Health Behavior Interventions

Abstract

Objective: To evaluate evidence of the effectiveness of computer-generated health behavior interventions—clinical encounters “in absentia”—as extensions of face-to-face patient care in an ambulatory setting.

Data Sources: Systematic electronic database and manual searches of multiple sources (1996–1999) plus search for gray literature were conducted to identify clinical trials using computer-generated health behavior interventions to motivate individuals to adopt treatment regimens, focusing on patient-interactive interventions and use of health behavior models.

Study Selection: Eligibility criteria included randomized controlled studies with some evidence of instrument reliability and validity; use of at least one patient-interactive targeted or tailored feedback, reminder, or educational intervention intended to influence or improve a stated health behavior; and an association between one intervention variable and a health behavior.

Data Extraction: Studies were described by delivery device (print, automated telephone, computer, and mobile communication) and intervention type (personalized, targeted, and tailored). We employed qualitative methods to analyze the retrieval set and explore the issue of patientinteractive computer-generated behavioral intervention systems.

Data Synthesis: Studies varied widely in methodology, quality, subject number, and characteristics, measurement of effects and health behavior focus. Of 37 eligible trials, 34 (91.9 percent) reported either statistically significant or improved outcomes. Fourteen studies used targeted interventions; 23 used tailored. Of the 14 targeted intervention studies, 13 (92.9 percent) reported improved outcomes. Of the 23 tailored intervention studies, 21 (91.3 percent) reported improved outcomes.

Conclusions: The literature indicates that computer-generated health behavior interventions are effective. While there is evidence that tailored interventions can more positively affect health behavior change than can targeted, personalized or generic interventions, there is little research comparing different tailoring protocols with one another. Only those studies using print and telephone devices reported a theoretic basis for their methodology. Future studies need to identify which models are best suited to which health behavior, whether certain delivery devices are more appropriate for different health behaviors, and how ambulatory care can benefit from patients' use of portable devices.

The number of controlled trials, reviews, and reports in the literature and popular media suggests that interest in using technology to augment patient– physician interactions has increased in the last decade. Recently, a JAMIA article recommended that telemedical services and information systems address behavior change, individual risk factors, and patient education, and further predicted that “the trend is toward delivery of care in an ambulatory setting or by interaction with a patient directly at home, and telemedicine services and information systems provide the necessary communication links.”¹

The purpose of this study is to report the current state of the peer-reviewed evidence for patient-interactive computer-generated health behavior interventions—clinical encounters “in absentia”—as extensions of face-to-face patient care. We were interested in two specific areas: the health behavior models used in these interventions and the devices used for patient education, counseling, and reminder systems aimed at improving patient health behaviors.

Background

Other Reviews

Other reviews have focused on a specific delivery method (e.g., telephone-delivered interventions) or a particular health behavior focus (e.g., smoking cessation). To our knowledge, this is the first review to summarize findings across all interventions that involve devices that communicate or interact directly with the patient, regardless of technology, health behaviors, or medical conditions. Intervention types are also defined more narrowly and more consistently than in previous literature reviews (as discussed under Methods). While other reviews describe the growing role of telecommunication in health care, this review specifically examines the state of computer-generated or computer-operated therapeutic communications. Table 1▶ summarizes previous review papers.

Table 1.

▪ Summary of Reviews and Analyses of Personalized, Targeted, and Tailored Interventions

Author	Intervention Focus	Method	Delivery Device
Skinner et al., 199371	Patient education	Overview, 31 articles and reviews	Computer-assisted instruction, telephone
Alemi and Stephens, 199672	Preventive care, ambulatory setting; patient education	Overview, 4 projects	Telephone, print materials
Shea et al., 199673	Preventive care, ambulatory setting	Meta-analysis, 16 trials	Computer-generated reminders
Balas et al., 199723	Distance medicine technology	Literature review, 61 trials	Computer systems, telephone
Piette, 199774	Diabetes management	Literature review, 33 studies	Telephone using AVM (automated voice messaging)
Balas et al.,199875	Diabetes management	Literature review, 15 studies	Computer systems, print materials
Marcus et al.,199876	Physical exercise	Literature review, 28 studies	Mass media-based interventions
Wagner, 199877	Mammography screening	Meta-analysis, 16 articles	Print materials
Bental et al., 199919	Patient information systems	Overview, 15 projects	Computer systems, print materials
Brug et al., 199918	Nutrition	Overview, 8 studies	Print materials
Kristal et al., 199978	Nutrition	Review, 10 studies	Print materials
McBride and Rimer, 199979	Telephone-delivery	Literature review, 74 trials	Telephone
Strecher, 199922	Smoking cessation	Literature review, 10 studies	Print materials

Theoretic Models

Patients are increasingly involved in managing their health care,² and health care providers are challenged to motivate, educate, and help people adhere to healthy behaviors and medication regimens in the ambulatory setting.³ Understanding why people behave the way they do and identifying the factors underlying behavioral change help in the development and evaluation of effective health behavior interventions.⁴ Although a review of theories is outside the scope of this paper, we mention the four cognitive-behavioral models used most frequently in the studies reviewed.

Cognitive-behavioral theories focus on the individual level and use two key concepts—behavior (as mediated through cognitions) and knowledge (which is necessary but not sufficient to produce behavior change). These theories focus on intrapersonal factors such as an individual's knowledge, beliefs, motivation, attitudes, developmental history, experience, skills, self-concept, and behavior. Models using an intrapersonal approach are the stages of change, or transtheoretic, model (TM), the health belief model (HBM), and the theory of reasoned action/theory of planned behavior (TRA).^5,6 The TM is concerned with an individual's readiness to change.^6,7 The HBM focuses on an individual's perception of the threat of a health problem.⁴ The TRA focuses on an individual's intention to perform a behavior.⁶ Social-cognitive theory incorporates intrapersonal and interpersonal factors; as in the HBM and TRA, the benefits of a behavior must outweigh the costs; also, a person must have a sense of self-efficacy or personal agency about the behavior.^8,9 Personal empowerment, an individual's ability to cope with situations and perceived sense of control over them, is emphasized.^8,10 Table 2▶ summarizes the concepts of each theory.

Table 2.

▪ Models and Concepts for Health Behavior Change

Concept	Definition	Application
Health Belief Model:
Perceived susceptibility	One's opinion of chances of getting a condition	Personalize risk based on a person's features or behavior.
Perceived severity	One's opinion of how serious a condition and its consequences are	Specify consequences of the risk and the condition.
Perceived benefits	One's opinion of the efficacy of the advised action to reduce risk or seriousness of impact	Define action to take; how, where, when; clarify the positive effects to be expected.
Perceived barriers	One's opinion of the tangible and psycho- logical costs of the action	Identify and reduce barriers through reassurance, incentives, assistance.
Cues to action	Strategies to activate “readiness”	Provide how-to information, promote awareness, provide reminders.
Self-efficacy	Confidence in one's ability to take action	Provide training, guidance in performing action.
Stages-of-Change Model:
Pre-contemplation	Unaware of problem, hasn't thought about changes	Increase awareness of need for change, personalize information on risks and benefits.
Contemplation	Thinking about change, in the near future.	Motivate, encourage to make specific plans.
Preparation	Making a plan to change	Assist in developing concrete action plans, setting gradual goals.
Action	Implementation of specific action plans	Assist with feedback, problem solving, social support, reinforcement.
Maintenance	Continuation of desirable actions, or repeating periodic recommended step(s)	Assist in coping, reminders, finding alternatives, avoiding slips/relapses (as applicable).
Theory of Planned Behavior and Theory of Reasoned Action:
Behavioral intention	Perceived likelihood of performing the behavior; prerequisite for action	Define action; identify how much effort one is planning to exert to reach goal.
Attitude	One's favorable or unfavorable evaluation of the behavior	Identify outcomes of action.
Behavioral belief	Belief that behavioral performance is asso- ciated with certain attributes or outcomes	Provide information about outcomes; clarify positive effects to be expected.
Normative belief	Subjective belief regarding approval or disapproval of the behavior	Identify barriers and advantages of behavior.
Subjective norm	Influence of perceived social pressure; weighted by one's motivation to comply with perceived expectations	Identify specific groups or individuals of influence; identify how much their approval or disapproval affects action.
Perceived behavioral control (Theory of Reasoned Action only)	One's perception of how easy or difficult it will be to act	Incorporate information about likely results of action in advice.
Social Cognitive Theory:
Reciprocal determinism	Behavior changes result from interaction between individual and environment	Work to change environment.
Behavioral capability	Knowledge and skills to influence behavior	Provide information and training about action.
Expectations	Beliefs about likely results of action	Incorporate information about likely results of action into advice.
Self-efficacy	Confidence in ability to take action and persist in action	Point out strengths; use persuasion and encouragement; approach behavior change in small steps.
Observational learning	Beliefs based on observing others	Point out others' experience; identify role models.
Reinforcement	Responses to a person's behavior that increase or decrease chances of recurrence	Provide incentives, rewards, praise; encourage self-reward.

Sources: Bandura,⁸ Glanz et al.,⁴ Prochaska et al.,^7,41 Rhodes et al.,⁵ and Skinner and Kreuter.⁶

An appropriate theoretic framework applied to development of health behavior messages can greatly enhance a patient's motivation to comply with an intervention.⁵ Further enhancement can be achieved using patient characteristics in conjunction with computer production capabilities to approximate a face-to-face clinical encounter.⁶

Another enhancement feature may be achieved by using mobile devices rather than delivery methods that tether ambulatory patients to a computer, telephone, or mailbox. Mobile devices such as cell phones or pagers are particularly suitable for outpatient interventions, since patients can carry them easily. These devices have received considerable popular media and commercial attention,^11–13 so we made an effort to find papers that described their use. The price of mobile communication devices has dropped dramatically in the last decade, so the increasing power and decreasing cost of communication may provide opportunities for therapeutic interventions that were not feasible before. In addition, their portability and convenience seem to create an attachment or synergy between the user and the device, which can bond the user to the intervention protocol.¹⁴

Methods

The literature that describes this area of investigation is not indexed in a single database. We therefore designed a search strategy that involved searching across multiple databases using both free text and appropriate specialized terminology.

Data Sources

Databases searched included medline (1966–99), HealthSTAR (1981–99), cinahl (1982–99), Current Contents (1997–99), embase (1990-1999), inspec (1969–1999), PsycINFO (1967–1999), and Sociological Abstracts (1986–1999). We also searched the Cochrane Collaboration and Web of Science (Science Citation Index Expanded and Social Sciences Index) databases. To account for gray literature, we searched CRISP (Computer Retrieval of Information on Scientific Projects) and Dissertation Abstracts, contacted authors, and conducted targeted Internet searches. We also searched lexis-nexis for more popular literature on this subject.

Searches were limited to publications in English. A summary of key terms and phrases is given in Table 3▶.

Table 3.

▪ Key Words Used in Literature Review

Key Words	Additional Terms
Compliance	Adherence
	Motivation
Patient education	Education
	Decision making
	Empowerment
Preventive health services	Self-help
	Health behavior
	Ambulatory care
Reminder systems	Drug monitoring
	Intervention
	Patient reminder
	Tailored reminder
	Targeted reminder
	Tailored intervention
	Targeted intervention
Computer	Computer communication networks
	Computer systems
Telephone	Telephone systems
Pager	Paging technology
Print communication	Letter
	Postcard
Communication	Counseling
	Self-assessment

Study Selection

Eligibility for inclusion in the final set included:

• Controlled clinical trials and quasi-experimental studies with some evidence of instrument reliability and validity

• At least one patient-interactive feedback, reminder, or educational intervention intended to influence or improve a stated health behavior

• An association between one intervention variable and a health behavior

Eligible trials were evaluated using the rating system described in Table 4▶. Ratings were based on recommendations from the literature.^15,16 Articles received a score from 1 to 10; sampling and randomization aspects and presence of a control group were weighted most heavily (totaling 7 points). The minimum score was set at 5 for inclusion.

Table 4.

▪ Rating System

Factor	Description	Possible Points
Randomization	Assignment to different interventions by chance	2
Control group	Comparison made to group of subjects not given the health behavior intervention	2
Theory or model used	Theoretic basis for intervention design	1
	Rationale for using chosen model and rejecting other options
Sampling	Sampling method described	3
	Sample composition clearly described
	Sample of adequate size
	Number and ratio of withdrawals described
Analysis of main effect variables	Clear definition for each variable	1
	Clear description of methods and results
	Numeric table presented for each effect variable
Content	Intervention clearly described and replicable	1
	Discussion of withdrawals
	Discussion of study limitations

The initial cross-database search yielded 1,404 publications; this was reduced to 519 after elimination of duplicates. Review of the title and abstract of each publication yielded 97 publications potentially meeting eligibility criteria. After review of these articles, 49 publications were eliminated because they did not meet the eligibility criteria (the primary cause was a focus on physician reminders). Manual searches of the bibliographies of remaining articles, reviews, key journals in the appropriate fields, and key individuals yielded another 6 articles, for a total of 55; multiple reports of studies were collapsed to yield a final total of 46 studies in this review. Nine of these are feasibility or quasi-experimental studies included because they describe promising approaches. Figure 1▶ illustrates our selection process.

Figure 1.

Search and selection process.

Data Extraction and Definitions

Each item was scored using the rating system described in Table 1▶. Items were classified by intervention type, delivery device, and use of synchronous vs. asynchronous interaction.

We defined three intervention types according to features accepted in the literature: personalized, targeted, and tailored. Personalized messages have the person's name on the information he or she receives. The message content is not adapted to the individual's diagnostic, behavioral or motivational characteristics.¹⁷ Personalized intervention studies were eliminated unless a higher level intervention (i.e., targeted or tailored, or both) was also a condition in the study.

Targeted message content is customized to reach a specific subgroup of the general population, based on the principles of market segmentation. Content is customized to “target” broad psychographic (i.e., activities, interests, and opinions) and sociodemographic groups. Targeted interventions do not account for personal differences in intervention needs among individuals in the target population, but they may be personalized.¹⁸

Tailored interventions are messages or a series of messages based on a specific individual's characteristics, as determined through historical records, replies to questions, or replies to previous messages. Tailored messages are generally based on published theoretic models, and message content is specific to one individual at one point in time. One of the goals of a tailored intervention is for patients to perceive the information as applying only to them.^17,19,20 An example of a tailored intervention is delivering messages or information contingent on a patient's “stage of change,” a model postulating that patients will respond to and better remember messages presented on cue. For instance, patients who have just quit smoking will respond better to messages pitched to the “action” phase than the “precontemplative” phase.^21,22 The actual messages are picked from a large pool of potential responses either manually by a therapist or through a largely automated process designed by a therapist.

The primary distinction between targeted and tailored interventions is that tailoring adapts content or the way content is presented according to the needs of the individual. Material is not fixed and feedback is based on individual, not subgroup, characteristics. Devices used for feedback range from the most simplistic, such as tailored letters, to expert systems incorporating behavior change models into an interactive messaging system.

Interventions can be distinguished along a continuum, from generic (or “one-size-fits-all”) to highly individualized, tailored approaches as seen in Figure 2▶. Confusion between targeted and tailored interventions is compounded by researchers' inconsistent use of the terminology.²²

Figure 2.

Intervention types continuum.

We grouped intervention delivery devices into categories adapted from Balas et al.²³: 1) mobile communication systems (use of a pager, mobile telephone, or other wireless system for delivery), 2) computerized communication systems (use of a computer, modem, touch-sensitive screen, or other interfacing equipment for delivery), 3) automated telephone communication (usually computer-generated messages using a regular telephone line and telephone), and 4) print communication (use of a letter, bulletin, fax transmission, newsletter, postcard, or manual delivery).

We also distinguished between synchronous and asynchronous communication. Synchronous communication is like communication by telephone—dialog occurs in real time. Asynchronous communication is like e-mail—two parties carry on a dialog by leaving messages, but do not usually communicate in real time.

Results

Of the 46 studies meeting our inclusion criteria, 9 received scores below 5. These studies were excluded from analysis but are included in Table 5▶ because they illustrate promising approaches and merit discussion.

Table 5.

▪ Summary of Targeted and Tailored Interventions, Categorized by Delivery Device

Author[s]	Methods	Health Behavior	N	Results	Score
Mobile Communications:
Facchinetti & Korman, 1996,62199863	Quasi-experimental controlled trial	Medication adherence: reduce drug holidays	24	Text pager improved adherence, reduced number of “drug holidays” and total number of days without therapy.	4
	Reminder system vs. control
	Targeted, asynchronous
	(PRN: Prescription Reminder Network)
Milch et al.,199664	Quasi-experimental	Medication adherence: increase compliance	6	Mean compliance rose from 56% to 96% during pager use.	1
	Medication use before (control period) and during pager use
	Targeted, asynchronous
	(Neuropage)
Dunbar et al., 200065	Quasi-experimental	Medication adherence: increase compliance	26	Patients on HIV medications reported high acceptance of paging system.	2
	Interactive reminder system
	Targeted, synchronous
	(CareWave)
Computer Systems:
Shultz et al.,199257	RCT: Transmission of glucometer results via modem once a week vs. standard diary results	Diabetes: reduce blood glucose levels	20	Significant improvement in reduced blood glucose levels in modem intervention group over traditional diary group.	6
	Targeted, synchronous
Turnin, 199258	RCT: Diabeto use (computer-aided instruction) vs. no Diabeto use	Diabetes: increase dietetic knowledge and improved diabetes self-care	105	Diabeto use associated with significant improvement in dietetic knowledge, some decrease in caloric excess in overeaters, decrease in fat intake in over-consumers, increase in carbohydrate intake in under- consumers; no impact on caloric deficit.	9
	Tailored, synchronous
	(Diabeto)
Buchanan et al., 1993,59 199560	Quasi-experimental	Migraine: improve understanding of migraines	16	Presentation of information based on individual patient's medical record, concerns, questions, and physician input.	1
	Interactive explanation system			System “accepted by patients.”
	Tailored, synchronous
	(Migraine)
Carenini et al., 199461	Quasi-experimental	Migraine: improve understanding of migraines	16	Presentation of information based on individual patient's medical record, concerns, questions, and physician input.	1
	Interactive explanation system			Patients “found system useful.”
	Tailored, synchronous
	(Migraneur)
Gustafson et al., 1994,55 199956	RCT: CHESS use vs. no CHESS use	Information and support: improve social support, mood, and quality of life	204	CHESS users reported improved cognitive functioning, sense of social support, and more active life; reported more participation in health care and decreased levels of negative emotions.	9
	Tailored, synchronous			No significant differences between groups for depression, physical functioning or reported level of energy.
	(CHESS: Comprehensive Health Enhancement Support System)
Binsted et al., 199580	Quasi-experimental	Diabetes: improve diabetes self-care	10	Generation of diabetes information collected through medical record; includes personalized reminders.	1
	Interactive explanation system			Patients and medical staff found system helpful and easy to use.
	Tailored, synchronous
	(PIGLET: Personalized Intelligent Generator of Little Explanatory Texts)
McRoy et al., 199883	Quasi-experimental	Medical history taking: increase understanding of medical conditions and treatment	35	User satisfaction measured via online questionnaire: 87% of users completed evaluations; 87% prefer online system to paper.	1
	Generation of customized educational materials and medical explanations			Other findings: users like having medical information tailored to their interests; 71% found definitions somewhat or very helpful; 58% found dialog sections helpful.
	User satisfaction questionnaires completed online
	Tailored, synchronous
	(LEAF: Layman Education and Activation Form)
Jones et al., 1996,81 199982	RCT: Personalized cancer information (P) vs. general cancer information output via “computer consultation” (G) vs. cancer booklet (B) information group	Information and support: increase understanding of cancer information	525	P reported higher satisfaction with information, thought information was relevant, and learned something new.	9
	Tailored, synchronous			B more likely to feel overwhelmed by information than P or G. P and G thought information was limited.
				Printed information use at home: 83% B; 57% G; 70% P.
				P and G groups also sent printouts of information viewed; P more likely to use this information than G.
Rolnick et al., 199954	RCT: CHESS use vs. no CHESS use (included receiving a book related to either HIV or breast cancer)	Information and support: improve social support, mood and quality of life	107	HIV group: discussion service used more often (time and number of uses).	9
	Targeted, synchronous			Breast cancer group: discussions were “disease-based.”
	(CHESS)
Automated Telephone Communications:
Ahring et al., 199251	RCT: Transmission of glucometer results via telephone once a week vs. standard diary results every 6 weeks	Diabetes: reduced blood glucose levels	42	Significant difference in blood glucose levels between 6-week and 12-week experimental groups.	6
	Targeted, asynchronous			Approximately two thirds of experimental group expressed increased understanding of blood-glucose control, motivation for self-management and general knowledge about diabetes.
Stehr-Green 199349	RCT: Computer-generated telephoned immunization reminders vs. control	Preventive health: increase immunization rate	222	11.6% improvement in immunization rates in intervention group. On-time immunizations: 52.9% intervention, 41.3% control.	9
	Targeted, asynchronous.
Friedman et al., 1996,44 199745	RCT: TLC use vs. no TLC use (control)	Hypertension: increase medication compliance and lower blood pressure	267	Medication adherence: improved 17.7%–18% in TLC, 11.7%–12% in control. If nonadherent at baseline: 36% improvement TLC, 26% control.	10
	Tailored, synchronous			Blood pressure: mean systolic and diastolic blood pressure decreased in both groups.
	(TLC: Telephone-linked Care)
	Model: social cognitive theory
Hyman et al., 199650	RCT: Computer-interactive phone call re: total cholesterol and weight vs. no call (control)	Preventive health: decrease cholesterol level and body weight	115	Subjects recruited from those who completed a 4-week cholesterol behavioral and diet program.	9
	Targeted, synchronous			No significant difference between experimentals and controls.
Baer and Geist, 199784	Quasi-experimental	Mental health: increase adherence to behavior therapy program	65	Patients who completed two or more phone sessions were “greatly improved.”	2
	Computer-administered behavior therapy program (BT STEPS) using interactive voice response (IVR)
	Tailored, synchronous
	Model: “behavioral theory”
Jarvis et al., 199747	RCT: TLC vs. control	Physical exercise: increase activity	52	Increase in stage of change: TLC 88%, control 62%.	7
	Tailored, synchronous
	Model: stages of change
Piette and Mah, 199753	Feasibility study	Diabetes: improve diabetic self-care	65	98% reported no difficulty under-standing and responding to AVM queries. AVM system could identify potentially serious health problems. 71% were willing to listen to preventive care messages.	2
	Automated voice message (AVM) calls vs. no calls
	Targeted, synchronous
Friedman, 199846	RCT: Report of three TLC studies: hypertension medication adherence (MA); dietary modification (DietAid); exercise (ACT)	Hypertension: increase medication adherence and lower blood pressure	267	MA: 18% mean adherence improvement in TLC users vs. 12% control. TLC diastolic blood pressure reduction 5.2 mm Hg vs. 0.8 mm Hg in control.	10
	TLC use vs. no TLC use (control)	Physical exercise: increase activity		DietAid: TLC reduced mean total cholesterol vs. no change in control.
	Tailored, synchronous			ACT: TLC increased walking to 121 min/week vs. 40 min/week in control.
	Models: social cognitive theory, stages of change
Lieu et al., 199848	Randomized trial: Automated telephone call (TC) vs. letter only (L) vs. TC followed by L (TC+L) vs. L followed by TC (L+TC)	Preventive heath: increase immunization rate	648	TC+L and L+TC led to significantly higher immunization rates than L or TC.	8
	Targeted, asynchronous
	Model: health belief
Meneghini et al., 199852	Controlled trial	Diabetes: lower diabetes or hypoglycemic crises and emergency room visits	107	58% of clinic patients used ECM.	5
	Daily report of self-measured glucose levels or hypoglycemic symptoms via voice-interactive phone system vs. no ECM use			Three-fold decrease of diabetes-related crises or hypoglycemia in ECM group. Two-fold decrease in clinic visits of complex diabetes management issues.
	Targeted, synchronous
	(ECM: Electronic Case Manager)
Print Communications:
Prochaska et al., 199341	Randomized assignment via stage of change	Smoking cessation: abstinence from smoking tobacco	756	ITT outperformed other conditions at each f/u point and demonstrated higher prolonged abstinence rates than other groups.	8
	Standardized self-help manual (ALA+) vs. manual matched to stage (TTT) vs. interactive computer report plus individualized manual (ITT) vs. four counselor calls plus stage manual plus report (PITT)
	Tailored, asynchronous
	Model: stages of change
Campbell et al., 199426	RCT: Well-child appointment letter vs. postcard vs. control	Preventive health: increase immunization rate	558	Letter and postcard rates significantly higher than control rates (75.0%, 73.7%, and 67.5%, respectively).	10
	Targeted, asynchronous			No difference between letter and postcard groups.
	Model: health belief model
Campbell et al., 199431	RCT: Multicenter study.	Nutrition: lower fat intake	558	Tailored group was more than twice aslikely as non-tailored group to remember receiving information.	10
	Tailored nutrition information packet vs. non-tailored packet vs. control			Tailored group significantly reduced total fat and saturated fat intakes compared with control.
	Tailored, asynchronous
	Models: health belief model; stages of change
Osman et al., 199489	RCT: Computer-generated tailored asthma education booklet (BI) vs. standard oral education (control)	Asthma: decrease hospital admissions	801	BI associated with reduction in hospital admissions for patients judged most vulnerable on study entry.	9
	Tailored, asynchronous
Rimer and Orleans, 199486	Controlled trial	Smoking cessation: abstinence from smoking tobacco	901	GC used Clear Horizons Guide tailored to older adult population.	8
	Tailored guide and counselor calls (GC) vs. standard guide (G) vs. control (CO)			20% of GC reported not smoking 12 months after intervention vs. 12% of G.
	Tailored, asynchronous			Higher proportion of both GC and G used quitting techniques, were more likely to set a quit date and use nicotine reductiontechniques than controls.
Skinner et al., 199429	RCT: Individualized mammogram recommendation letters vs. standard letter	Preventive health: increase mammogram rate	435	Individualized letter recipients were more highly associated with mammogram follow-up if income<$26,000 or if African-American.	10
	Tailored, asynchronous			Overall, individualized letters were better remembered and more thoroughly read than standard letters
	Model: stages of change			Higher-educated women less likely to report interest in content.
Strecher et al., 199443	RCT: Tailored letter vs. generic letter vs. control	Smoking cessation: abstinence from smoking tobacco	51 &197	Younger smokers more likely to quit	10
	Tailored, asynchronous			Significant effects of tailored letters only for moderate to light smokers.
	Models: health belief, stages of change
Brug et al, 1996,32 1998,33 1999a,34 1999b35	RCT: Tailored vs. non-tailored1996 and 1999b: Tailored vs. general nutrition information	Nutrition: lower fat intake, increase fruit and vegetable intake	1996, 1999b: 347	1996: Significant short-term effect of tailored messages on fat intake and opinions about vegetable and fruit intake. No significant effect on fruit and vegetable intake.	10
	1998: Tailored letter and iterative feedback (TI) vs. tailored letter (TL) vs. general letter (CO)		1998: 762	1998: TI and TL lower mean fat scores than CO. TI and TL higher mean vege- table scores than CO. No significant differences between TI and TL groups.
	1999a: Tailored feedback vs. tailored feedback and psychosocial information letter		1999a: 315	1999a: Significant reduction in mean fat score. Mean fruit intake increase. No vegetable change.
	Tailored, asynchronous			1999b: Personalized dietary and psycho- social feedback more likely to be read, seen as personally relevant and motivating to reduce fat intake.
	Models: social cognitive theory, theory of planned behavior
Kreuter and Strecher, 199688	RCT: Enhanced health risk assessment (HRA) vs. standard HRA vs. control	Preventive health: decrease fat intake and cholesterol and increase activity	1,317	Each behavior analyzed separately.	10
	Tailored, asynchronous			Enhanced HRA led to statistically or nearly statistically significant effects for cholesterol test, fat reduction, and exercise.
	Models: health belief, stages of change
Campbell et al., 199767	RCT: Risk result feedback vs. control	Preventive health: increase Pap test rate	411	No statistical difference between groups.	9
	Targeted, asynchronous			Women 50 to 70 years old who received results were “more likely” to have a Pap test in the next 6 months.
Baker et al., 199825	RCT: Personalized targeted reminder letter from physician vs. personalized postcard from physician vs. generic postcard vs. control	Preventive health: increase influenza immunization rate	24,743	64% of targeted letter group remembered reminders vs. 39% combined postcard groups.	9
	Targeted, asynchronous			Targeted letter more effective than either postcard intervention.
Dijkstra et al., 199839,42	RCT: Information on outcomes of quitting (O); self-efficacy-enhancing information (SE); O + SE; or no information (CO)	Smoking cessation: abstinence from smoking tobacco	752	Subjects considering change benefited most from O + SE intervention; those planning to quit benefited most from SE intervention.	10
	Tailored, asynchronous			Significantly more smokers in O, SE, and O + SE interventions attempted 24-hour quits.
	Model: stages of change
Dijkstra et al., 199838	RCT: 3 tailored letters and self-help guide (3TS) vs. 3 tailored letters only (3T) vs. 1 tailored letter and self-help guide (TS) vs. 1 tailored letter only (T) vs. non-tailored intervention (CO)	Smoking cessation: abstinence from smoking tobacco	752	3TS and 3T: more stage transition; higher intention to quit than CO; higher impact than TS or T.	10
	Tailored, asynchronous			TS led to more quitting behavior than CO.
	Model: stages of change			No difference between T and CO.
				In heavy smokers, tailored messages did not lead to more quitting than TS, T, or CO.
Greene and Rossi, 199836	RCT: 1 dietary feedback report and educational materials vs. control. Fat intake and stage-of-change assessments at 0, 6, 12, and 18 months	Nutrition: lower fat intake	296	Rate of progression to action stage by 18 months was found in 9%–12% of subjects in precontemplation or contemplation stage; 24% preparation stage subjects; 40% unclassified subjects.	10
	Targeted, asynchronous
	Model: stages of change
Marcus et al., 199885	RCT: Individual motivationally-tailored reports (IT) VS. standard self-help booklets (ST)	Physical exercise: increase activity	194	IT: significant increase in physical activity each week and self-reported time exercising; more likely to reach action stage of motivational readiness for physical activity adoption.	10
	Targeted, asynchronous
	Models: stages of change, health belief
Bastani et al., 199927	Randomized 2-group design	Preventive health: increase mammogram screening	901	8% increase in mammography after intervention.	10
	Educational booklet and personalized health risk letter			No intervention effect in women under 50 years of age.
	Tailored, asynchronous
Bull et al., 199968	Clinical controlled trial	Physical exercise: increase activity	763	No significant differences between groups.	10
	Tailored pamphlet vs. standard pamphlet vs. control
	Tailored, asynchronous
	Model: stages of change
Campbell et al., 199987	RCT: Multi-level, multi-component intervention	Nutrition: lower fat intake, increase fruit and vegetable intake	459	Recall receiving bulletin: 72.9% SPIR, 64.6% EXP, 38.2% control.	10
	Bulletin-orientations: expert (EXP) vs. spiritual and pastor-oriented (SPIR) vs. standard			High trustworthiness: 63.5% SPIR, 53.6% EXP, 48.6% control.
	Tailored, asynchronous			High credibility: 45% SPIR, 31% EXP, 33% control.
	Model: stages of change			Fruit/vegetable intake: SPIR did not differ significantly from EXP. SPIR and EXP mean consumption significantly higher than control.
				High impact of pamphlets: 58% SPIR, 45% EXP.
Dijkstra et al., 199940	RCT: Multiple tailored (MT) vs. single tailored (ST) letters vs. standard self- help guide (SHG) vs. control (CO)	Smoking cessation: abstinence from smoking tobacco	843	MT had more effect than SHG or ST.	10
	Tailored, asynchronous			ST had more effect than CO.
	Model: stages of change
Lutz et al., 199937	RCT: Tailored newsletter with tailored goal-setting component (TG) vs. tailored newsletter without goal-setting component (T) vs. non-tailored newsletter (NT) vs. control (CO)	Nutrition: increase fruit and vegetable intake compared with control	710	Daily fruit and vegetable intake was higher for all 3 newsletter groups	10
	Tailored, asynchronous			Differences from baseline to post-intervention were greatest in TG; next was T, then NT.
	Models: social cognitive theory, stages of change			No statistically significant differences among tailored newsletter groups.
Myers et al., 199930	RCT: Minimal intervention (MI) vs. enhanced intervention (EI)	Preventive health: increase prostate cancer screening rate	413	Age of 50 years or older positively associated with adherence. Married men more likely to adhere. Belief in having an early detection exam in the absence of symptoms predicted adherence.	10
	Tailored, asynchronous
	Model: preventive health, a combination of health belief model, theory of reasoned action, and social cognitive theory
Raats et al., 199966	Clinical trial.	Nutrition: lower fat intake	171	No real difference between groups.	8
	Tailored feedback vs. no feedback
	Tailored, asynchronous
	Model: theory of planned behavior
Rimer et al., 199928	Randomized trial	Preventive health: increase Pap and mammogram screening rates	1,318	TPC+TTC did not perform better than PI.	8
	Provider prompting alone (PI) vs. provider prompting and tailored print materials (TPC) vs. provider prompting and tailored print materials and tailored phone counseling (TPC+TTC)			TPC+TTC: 35%–40% increase for Pap tests and overall cancer screening.
	Tailored, asynchronous			Subgroup findings: TPC+TTC most effective on Pap among women who worked for pay and those who viewed interventions as “meant for them.” TPC+TTC most effective for mammo- graphy among married women.
	Model: stages of change
Velicer and Prochaska, 199990	Report of 4 studies	Smoking cessation: abstinence from smoking tobacco	756 to 4,144	Cessation rates: 22%–26%	8
	Computer-generated (Pathways to Change expert system intervention) tailored report
	Tailored, asynchronous
	Model: stages of change

Notes: RCT indicates randomized controlled clinical trial.

Lack of homogeneity among the remaining 37 studies precluded pooling of data; our findings, therefore, form a descriptive literature review. Studies varied by recruitment method, subject characteristics, study design, time frame, setting, measurement of effects, and health behavior focus. Many studies reported multiple outcomes; several used targeted or tailored interventions in conjunction with personalized or generic interventions; some used more than one targeted or tailored intervention.

Of 37 studies, 33 (89.2 percent) reported improved outcomes and 20 of these (60.6 percent) were statistically significant. Fourteen studies used targeted interventions; 23 used tailoring. Eleven of the targeted intervention studies (78.6 percent) reported improved outcomes; 6 of these (54.5 percent) were statistically significant. Of the 23 tailored intervention studies, 22 (95.7 percent) reported improved outcomes; 15 of these (68.2 percent) were statistically significant. Table 5▶ lists the studies by delivery device.

No Intervention Benefits

Four studies^50,66–68 did not report statistically significant or improved outcomes. Lack of effect was explained by use of a limited, non-intensive one-time feedback with no inclusion of psychosocial factors⁶⁶ and use of similar messages for both control and intervention protocols.⁶⁸

Use of Models

Only 23 studies (62.2 percent) stated use of a theory to guide the health behavior intervention: 19 were print communications, 4 were telephone.

Comment on Emerging Technologies

Clinicians' use of pagers, personal digital assistants, PalmPilots, and laptop computers as portable information resource devices is a subject of numerous studies.⁶⁹ Just as clinicians have found that these devices provide a greater sense of control, mastery, and personal empowerment in the work setting, perhaps patients may also find such devices advantageous when managing their treatment regimens in the outpatient setting. Portability of “always ready” devices in combination with the messaging interventions can create a synergistic feedback loop between patient and device as evidenced by Milch's finding⁶⁴ that “several of the patients allowed that the pager became a trusted friend” and Dunbar's report⁶⁵ of high patient engagement with a pager system.

Mobile systems may have clear advantages over computer, telephone, or print communication systems for delivery of tailored health behavior interventions, because they offer the benefits of constancy—”anytime, anywhere” messaging and communication capability¹⁴; physical freedom—because the system is wireless and mobile, the patient is not restricted to one physical environment to receive messages¹⁴; privacy—messages can be modified so that others cannot observe or interact with them¹⁴; and temporal flexibility—users can interact with the content when available or postpone interaction if desired.²⁴

Yet a portable system is not without limitations and disadvantages. Potential problems include acceptance—studies reporting general acceptance of computerized and mobile delivery systems have had small numbers of subjects, so we do not know whether a selection bias or novelty variable is involved in this outcome; intrusiveness—the “anytime, anywhere” feature may be too intrusive for long-term use; and economic consequences—we do not know how a portable system may economically affect a patient, a practitioner, or the health care system. Only 13 studies in this review^* considered cost as a factor of a system's feasibility or success.

Conclusion

Our review indicates that many studies demonstrate the effectiveness of “clinical encounters in absentia,” but few good studies incorporate leading edge communication technologies. The studies reviewed here represent the best available evidence to date of the effectiveness of targeted and tailored health behavior interventions across health behaviors.

An overwhelming majority (91.3 percent) of tailored intervention studies reported improved outcomes, as did 92.9 percent of those studies that used targeting; however, little research compared tailored to targeted interventions. We therefore cannot conclude that tailoring is more effective than targeting. One notable exception is Prochaska et al.⁴¹ Using the stages of change model to characterize readiness to quit smoking, they compared two tailored interventions to a targeted condition and general smoking cessation materials. At the 18-month follow-up period, tailored interventions outperformed both targeted and generic conditions and were associated with higher prolonged abstinence rates than other conditions. This study offers evidence that tailored interventions can more positively influence health behavior change than targeted, personalized, or generic interventions, but more studies like this need to be conducted.

There has also been little research comparing different tailoring protocols to one another. One group of smoking cessation studies compared three types of tailored interventions matched to stage of change to controls,^39,42 four types of tailored interventions to a nontailored intervention,³⁸ and two types of tailored interventions to generic material and controls.³⁶ Two patterns emerged: there was more forward stage transition in the tailored groups compared with controls, and multiple interventions were more effective than single tailored interventions. Studies of this kind must be conducted for health behaviors other than smoking.

It is notable that only those studies using print and telephone devices reported a theoretical basis for their methodology. Future studies need to identify which models are best suited to which health behaviors and whether certain delivery devices are more appropriate for different health behaviors. While “it is not inconceivable to view computer technology for health promotion and the delivery of services as a form of medical intervention with patient satisfaction, compliance, and improved health status as the goals,”³ we need to know to what extent such interventions can beneficially replace interpersonal health behavior recommendations. In addition, usability studies could elucidate the complex process of human interaction with technology—the interplay between interface design and human cognition. The current research shows that isolated paper, telephone, and computer-delivered communications can cause health-enhancing behavior change. The communication of these behavior change models over an integrated Internet linked array of delivery devices, pagers, cell phones, interactive television, and computers with portable devices is technically feasible today.

Friedman et al.⁴⁵ have stated that “in the future there will be devices in general use that will incorporate features of the current telephone, television, video, and computer as well as wireless devices that people will be able to carry with them.” That future is currently possible through the use of tetherless devices such as pagers and personal digital assistants, but research on these devices currently lags far behind research on print, telephone, and computerized communications.

In 1997, Balas et al.⁷⁰ predicted that, “in the future, application of distance technology may strengthen the continuity of care between patient and clinician by improving access and supporting the coordination of health care activities from a single source.”²³ Technology has finally reached the point that health behavior models can be integrated with computer-generated interventions to provide consistent, continuous interactive ambulatory care. What is missing is comprehensive measurement of the effectiveness of these systems, which has the potential to not only inform the organization and delivery of health care but help move the science of medical informatics toward the goal of achieving the status of a “mature science.”