Carol Pilgrim

Improving clinical breast examination training in a medical school: a randomized controlled trial

To evaluate a new program for teaching clinical breast examination, a class of 156 second-year medical students were randomized into an experimental group (practice and feedback on silicone breast models and women volunteers) and a control group (lecture only). During a simulated practical clinical examination routinely conducted at the end of the second year, the experimental group students used more suggested palpation techniques during a patient examination (4.6 vs 2.0; p<0.0001) and found more simulated lumps in a silicone model (4.7 vs 4.4; p<0.05). Practice with immediate feedback is more effective than lecture alone in teaching clinical breast examination.

10 Stimulus equivalence: A class of correlations, or a correlation of classes?

Publisher Summary The chapter discusses stimulus equivalence and describes experiments in which the reversals of baseline conditional discriminations appear to have different effects across probe trial types (i.e., reflexivity, symmetry, and transitivity/equivalence). It examines other empirical evidence performance on the various probe trial types that may differ in potentially important ways and reviews studies that use measures other than probe trials to assess equivalence-like phenomena. The theme considered throughout is a fundamental one for even the simplest of analytic units. The mathematical definition of equivalence specifies only required test outcomes, not the make-up of the behavioral unit(s) that includes these outcomes. The predictive value of the set theory framework is undeniable, and the structured approach that this framework has provided for the study and training of complex behavioral repertoires, often termed “cognitive,” has yielded impressive results. A definition of equivalence that allowed for correspondence among three independent stimulus control relations provides even greater generality while maintaining the precision and rigor of the set theory framework.

How do women compare with internal medicine residents in breast lump detection? A study with silicone models.

Objective:Manufactured silicone breast models were used to compare the accuracy of breast examination by 300 women and 62 internal medicine residents.Design:The study design was cross-sectional.Setting:The study took place in two teaching-hospital general medicine clinics.Patients/Participants:Women were continuing care patients, ages 40 to 68, with no current breast complaint; 300 of 467 (66%) randomly selected women participated. Physicians were internal medicine residents with at least one-half day per week of ambulatory care practice; 62 of 64 (97%) participated.Measurements and Main Results:Sensitivity equalled the percentage of 18 lumps correctly detected in examination of six silicone breast models. Specificity equalled the percentage of six models examined without a false-positive detection. Women’s sensitivity was lower than physicians’ (40% vs. 58%), but their specificity was higher (66% vs. 52%). For both women and physicians, sensitivity varied according to lump size, hardness, and depth, with women’s sensitivity lower than physicians’ for each characteristic. Examination duration was the technique most strongly and consistently related to accuracy. Physicians spent more time examining models than did women (2.5 vs. 2.1 minutes per model). For both groups duration related positively to sensitivity (r=0.46, women; 0.55, physicians) and negatively to specificity (r=−0.35, women; −0.59, physicians). After adjusting for differences in technique, women’s sensitivity remained lower than physicians’, whereas specificity generally remained higher. The sensitivity of physicians with prior tactile experience with breast lumps was higher than that of physicians without such experience (60% vs. 51%, p=0.01). Too few women (2%) had prior tactile experience to permit analysis.Conclusions:Women’s and physicians’ breast examination accuracies differ, but for the two groups accuracies vary similary by lump characteristics and examination technique. Programs to improve breast examination should focus on specificity as well as sensitivity. Training that includes tactile experience may be important.

The Human Subject

As the chapters of this volume and others (e.g., Davey & Cullin, 1988; Hayes & Hayes, 1992) attest, there are many important questions to be asked of and about human behavior. And as is the case with questions about animal responding, the natural science strategies of behavior analysis are particularly well-suited to identifying the variables of which human behavior is a function (e.g., Johnston & Pennypacker, 1993). Still, the translation of a research question and a scientific strategy into an actual experiment requires many practical decisions.

Stimulus Control and Generalization

The ability to identify possible sources of stimulus control, and to increase or decrease them, as necessary, is essential to effective autism service delivery. Thus, familiarity with the fundamentals of stimulus control should hold special significance for applied behavior analysts working in the autism field. This chapter provides an overview of some major areas of basic laboratory-based stimulus control research in behavior analysis, with particular attention paid to topics of potential relevance in the application of stimulus control procedures. Defining characteristics of three-, four-, and five-term contingencies are described here, issues in establishing these forms of stimulus control are discussed, and the nature of the stimulus classes that can result in each case are explored. While emphasizing behavior–environment interactions throughout, the literature reviewed here ranges from analysis of each element of an n-term contingency to syntheses of complex human repertoires. This inductive and translational approach stands to be enhanced, however, by appropriate integration of laboratory findings with applications in autism service delivery. The experimental behavior-analytic literature has important lessons to offer those practitioners wishing to better understand the stimulus control principles that can improve intervention effectiveness.