ABSTRACT
The interest of behavioral medicine researchers, along with that of most behavioral scientists, lies in understanding how people behave, feel, and think in the course of their day-to-day living. We are interested in whether (a) their blood pressure goes up when they encounter stress and drops when they sleep, (b) they experience more pain when they are active than when they are sedentary, (c) they are less likely to take their medication when they are faced with increased work demands, (d) they smoke more when they are upset and smoke less when they are calm, and so on. This interest in real-world behavior is seldom manifest in our research methods, which do not often directly study subjects’ day-to-day behavior. Instead, we often try to bring these real-world processes into the laboratory for controlled study with mixed success. Laboratory studies afford unparalleled control, but lack real-world realism or what has been called ecological validity (Brunswick, 1949). We have not successfully modeled in the laboratory the range of environmental inputs, stressors, or other influences that people experience in the course of their daily life. Of course, there are good reasons why this is the case. It is hard to realize in the laboratory all the “slings and arrows” of daily living, and it would be
unethical in some cases to reproduce in the lab some of the traumas and conflicts typical of real-world existence. Laboratory methods also usually ignore the temporal or longitudinal dimension of behavior-the fact that recent experience affects current experience and that many relevant behaviors change over time, (e.g., due to fatigue or habituation).
