Risky behaviors such as smoking, alcohol abuse, physical inactivity, and poor diet are detrimental to health and often co-occur. The majority of adults meet criteria for two or more risk behaviors (Fine et al., 2004
; Poortinga, 2007
). Tobacco users, in particular, tend to have poor behavioral profiles, with about 92% of smokers having at least one additional risk (Fine et al., 2004
; Pronk et al., 2004
). Multiple risk factors also appear more prevalent among men, younger adults, singles, those of lower social class, the economically inactive, the less educated, and chronically ill (Poortinga, 2007
; Pronk et al., 2004
The major causes of morbidity and premature mortality in the United States– heart disease, cancer, stroke, and diabetes–are influenced by multiple health behaviors. Over 80% of cardiovascular events are believed due to the lifestyle factors of smoking, inactivity, poor diet, and alcohol use (Stampfer et al., 2000
). When risk behaviors cluster, the negative effects on health are even greater. Having a combination of three risk factors rather than one, for example, more than doubles one’s risk of myocardial infarction (American Hearth Association, 1997
). Excess risks also lead to excess medical costs, with the effect believed to be multiplied rather than additive (Edington et al., 1997
; Shinton, 1997
). Longitudinal data indicate that effectively treating two behaviors reduces health care costs by about $2000 per year (Edington, 2001
To more comprehensively address the health needs of individuals and populations, greater efforts are being targeted at changing multiple risk behaviors. More effective reductions in morbidity and mortality may be seen if changes in multiple risk factors can occur together. Additionally, changing multiple health behaviors should result in more favorable benefits measured in terms of quality of life outcomes and healthcare costs and utilization. To date, however, the magnitude of the benefits from multiple risk factor interventions, or multibehavioral interventions, remains largely unknown.
To evaluate the effectiveness of interventions targeting multiple behaviors, methods are needed to quantify and report changes across several behaviors. Use of an outcome metric or a standardized assessment to describe change across behaviors would allow those analyzing and considering adoption of health promotion programs -- such as policymakers, organizational and government decision makers, healthcare practitioners and systems, researchers, and individuals -- to decide how to allocate their finite resources (time, money and psychological energy) to maximize health improvement (Woolf, 1999
). Such an index would ideally allow for comparison of outcomes from multibehavioral to single behavior interventions as well as allowing for evaluation of the overall impact on health behavior change.
In this special journal issue, the focus is on interventions designed to change multiple risk behaviors within individuals or populations. Briefly, to distinguish the two types of designs:
- Multibehavioral interventions within individuals aim to deliver all interventions to all participants with participants typically selected to be at-risk for all targeted behaviors.
- Multibehavioral interventions within populations provide a program of interventions to an entire community, with individuals in that community receiving attention only for the behaviors for which they are identified as at risk. That is, multiple risks are addressed within the community but not all community members receive intervention on all behaviors.
The methods discussed in the current paper are relevant to both designs.
With increased interest in multibehavioral interventions, the field will need ways to conceptualize the issue of overall behavior change. The current paper reviews five different methods for quantifying and reporting change in multibehavioral interventions. We discuss their interpretations, strengths, and limitations. For the less well known approaches, we include numeric examples to illustrate the methodology and interpretation.