INTRODUCTION

Clinical reasoning has been a topic of research for several decades. The history of this research is important as it provides insights into the various ways in which both cognition and clinical reasoning have been conceptualized over the years and provides a context for current understanding of clinical reasoning and the ways in which it is taught to novice health professionals. In this chapter we draw on two recent research studies which have investigated clinical reasoning as used by different health professionals. These studies (Loftus 2006, Smith 2006) were situated within an understanding of clinical reasoning derived from the variety of research approaches that have been used to study clinical reasoning.

Early research into clinical reasoning was based predominantly within the empirico-analytical paradigm. The first studies came from behavioural psychology, and were followed by studies based on cognitive psychology. A separate but related body of research, generally referred to as medical decision theory, adopted a more probabilistic and statistical approach to conceptualizing clinical reasoning. Research into novice/expert differences has also constituted a distinct topic throughout the history of research into clinical reasoning. In more recent years, research situated in the interpretive and critical paradigms has appeared and grown in volume, especially in healthcare professions other than medicine.

BEHAVIOURISM

The oldest research tradition in clinical reasoning is behaviourism. Behaviourism is the view that mental phenomena like clinical reasoning can be understood only by analysing behaviour. Behaviour such as clinical reasoning is taken to be a dependent variable, and the independent variables that produce it are the stimuli that might lawfully cause that behaviour. The behavioural laws that link stimuli to behaviour are assumed to be similar in kind to the laws of physics and chemistry. Internal states of consciousness are excluded from this view of psychology as being beyond scientific study. Some research into clinical reasoning has been conducted within the behaviourist paradigm. For example, Rimoldi (1988) tested diagnostic skills of medical practitioners and students in the 1950s and 1960s, showing that as expertise increased so the numbers of questions asked and the time taken to solve diagnostic problems decreased.

Behaviourism has affected the teaching of clinical reasoning and other skills. For example, the notion that students should receive immediate corrective feedback on their performance comes from behaviourism, as does the precept of providing explicit aims and objectives that are related to measurable outcomes (Custers & Boshuizen 2002, Greeno et al 1996, Smith & Irby 1997).

Many features of modern medical curricula that have a direct bearing on the way that clinical reasoning is taught and practised can be traced to influences from behaviourist principles. These features include frequent and progressive testing, and close monitoring of students (Custers & Boshiuzen 2002). Behaviourism may have many weaknesses but it has been of some benefit when intelligently applied. However, as an explanation of all learning, behaviourism is conceptually weak and does not go far enough. It ignores context, sociocultural interaction and intersubjectivity. In the endeavour to address some of these weaknesses cognitivism emerged as a more powerful conceptual model for thinking about mental phenomena such as clinical reasoning (Patel & Arocha 2000).

COGNITIVISM

Cognitive science seeks to account for intelligent activity as exhibited by living organisms or machines. Cognitivism replaced the behaviourist metaphor of cognition, as a black box having environmental inputs and behavioural outputs, with the metaphor of cognition as a form of computation and information processing, similar in kind to that carried out by computers.

Cognitivism allows for ‘mental’ structures and processes, whereas behaviourism does not. Information processing, memory representation and problem solving are three core concepts (Case & Bereiter 1984). There have been a number of attempts to characterize knowledge structures according to a cognitive view, and these feature prominently in much clinical reasoning research within the cognitive paradigm. The mental structures which purportedly play such a prominent role have included successively: categories, prototypes, instances, schemas, scripts and networks (Gruppen & Frohna 2002). Each concept was introduced in turn as a response to the perceived weaknesses of its predecessors. For example, according to the theory of instances, knowledge organization occurs around an individual instance rather than as an abstract based on several cases. This idea was proposed in response to the weaknesses perceived in the construct of prototypes (Brooks et al 1991, Homa et al 1981).

This preoccupation with mental structures and access to them is typical of cognitivism and is symptomatic of the underlying conceptual model of cognition as a form of computation. Along with the concern for cognitive structures is an interest in the cognitive processes by which individuals make use of such structures. The most popular process for utilizing these cognitive structures in clinical reasoning is held to be hypothetico-deductive reasoning.

HYPOTHETICO-DEDUCTIVE REASONING

Research investigating the hypothetico-deductive method as a foundation in clinical reasoning was divided by Bradley (1993) into two groups. Researchers in the first group used think-aloud protocols with patients or simulated patients (e.g. Elstein et al 1978). Those in the second group used case vignettes (e.g. Eddy & Clanton 1982). There were weaknesses with both kinds of study, such as the artificial nature of the think-aloud protocols that tended to be used. However, the concept of hypothetico-deductive reasoning is generally considered to be a robust element of the cognitive paradigm, and one that could be adopted in different models that may reject many of the assumptions of cognitivism. The cognitivist body of research also highlighted the differences between experts and novices in clinical reasoning.

EXPERT/NOVICE RESEARCH

Much of the effort in cognitivist research into clinical reasoning has consisted of attempts to delineate differences between novices and experts, which is therefore sometimes called the contrastive method. Most of this research has been experimental. A problem-solving approach is generally used, in which cognitive processes are studied in tasks that attempt to represent medical thinking. Typically, protocol analysis has been used, as in the work of Ericsson & Simon (1993), who claimed that experts’ use of forward-directed reasoning was ‘one of the most robust findings’ (p. 132) of research in this field. Forward reasoning is supposed to occur when someone gathers data and, with the aid of a great deal of pattern recognition invoking ‘if-then’ production rules, eventually reaches a conclusion (Patel & Groen 1986). Backward reasoning is supposed to occur when someone selects a hypothesis early and then proceeds to test it by gathering data that will confirm or refute it. This is believed to work well if the hypothesis is correct, but means that the problem-solver may need to start again if it becomes clear that the data being gathered tend to refute the hypothesis. This view of expert–novice difference is widespread in the clinical reasoning literature. It began about 1980 when researchers claimed that these differences existed between experts and novices in physics (Larkin et al 1980). These studies influenced the research of Elstein et al (1978) into clinical reasoning, seeking the same phenomenon of forward and backward reasoning.

The finding that forward and backward reasoning distinguish experts and novices has now been extensively investigated and ‘confirmed’ within medicine (Patel et al 1990), and is now widely accepted. However, the relevant studies were experimental and can be criticized as being highly artificial. In general they used written protocols, with all the relevant information presented simultaneously on a single page. The researchers asked individuals to read the case and verbalize or write down their thoughts. Analysis of these verbalizations produced the apparent distinction between forward and backward reasoning.

Variations on the research into novice–expert differences in reasoning have continued to recent times. For example, Norman & Schmidt (2000) also devised experiments to test forward and backward reasoning strategies among novices and experts. Their findings showed clearly that novices did better when using backward reasoning. This kind of finding has been used to provide a theory of what happens during problem-based learning, and this is why the hypothetico-deductive model is still an important theory in the teaching of clinical reasoning (Barrows & Feltovich 1987).

However, as Norman et al (1999) have observed, the concept of forward and backward reasoning is problematic owing to the artificial nature of the decontextualized settings in which it was established. In other words, these findings may be a laboratory artefact. Lemieux & Bordage (1992) discussed the issue of research into forward versus backward clinical reasoning at length. They concluded that laboratory-based studies were far too limiting, and that the results were often more a reflection on the method of investigation than the actual reasoning of the clinician. This criticism is supported by the work of Laufer & Glick (1996), who investigated novice–expert differences in real-world work settings, using an ethnographic approach informed by ideas from the cultural psychology of Vygotsky (1978, 1986).

Cognitivism entails an essentially individualistic view of expert–novice differences. Even as early as 1980, some researchers were dissatisfied with cognitivism as an explanatory model. For example, Norman (1980) complained that cognitivism was inadequate for conceptualizing the influence of interaction with others and the ways in which an individual’s personal life history and cultural background could affect reasoning skills. If cognition is in fact not a computational process then the search for the purported cognitive structures and processes may be misguided and doomed to failure. It can be argued that the similarities between cognition and computation are trivial, such as the ability to do simple mental arithmetic in one’s head. Much of the research referred to above, which sets out to establish the nature of the cognitive structures in clinical reasoning and other forms of cognition, assumes what it sets out to prove. The underlying metaphor of cognition being a form of computation is open to challenge. Humans undertake procedures such as mathematical calculations differently from computers, and the way they do them varies depending on the circumstances (Dreyfus 1992). Cognitivism has an essentially individualistic view that expertise in skills such as clinical reasoning is a collection of behaviours and thoughts which are unique personal constructions. This directly contrasts with the sociocultural view that expertise is fundamentally best viewed as a social phenomenon. From this perspective expertise would, in large part, be selective assimilations of prevalent social practices and values. There is limited research into clinical reasoning from a sociocultural perspective. Engeström (1995) used a sociocultural approach to study medical expertise in clinical consultations with real patients, and was able to richly describe and articulate his findings in a manner that would have been precluded by a purely cognitivist framework.

THE COGNITIVE CONTINUUM

There are other models for understanding clinical reasoning. There is wide acceptance of the notion that experts use intuition and pattern recognition. Intuition and pattern recognition are not well understood. The cognitive continuum is a construct that some have used in an attempt to accommodate all these different types of thinking within one model (Hamm 1988). The proposal is that different modes of thinking are invoked under different circumstances. For example, Hammond et al (1980) claimed that intuitive thinking is favoured when many cues are available. Dreyfus & Dreyfus (1986) argued that experience is crucial. An experienced clinician will resort to hypothetico-deductive thinking with an unfamiliar problem whereas novices must use it all the time until they acquire sufficient experience. Being on a cognitive continuum, these modes of thinking do not need to be mutually exclusive. The generation of a hypothesis may be intuitive and its subsequent testing can follow a more analytical path (Bradley 1993). Other authors (Higgs et al 2001) question the casual and pervasive use of the notion of intuition, regarding the use of advanced reasoning skills of experts to be a form of professional judgement and practice wisdom, grounded in deep experience-based knowledge, which is learned and is a highly refined form of reasoning ability. They see intuition as an important adjunct to reasoning.

MEDICAL DECISION THEORY

Another paradigm within clinical reasoning research dating back to the 1960s has been medical decision theory (e.g. Raiffa 1968, Sox et al 1988). This makes use of probability mathematics and logic as a theoretical lens and attempts to quantify the uncertainty of much clinical reasoning. Elstein et al (2002) maintained that such an approach encourages health professionals to adopt an evidence-based practice (EBP) approach. They asserted that even if a formal decision analysis is not possible this approach promotes a systematic appraisal of the trade-offs that need to be considered in a difficult decision. Medical decision theory has many attractions besides its associations with EBP. The possibility of making clinical decisions by calculation is seductive in an uncertain world where numbers appear to offer some degree of certainty. However, as Bradley (1993) pointed out, decision theory has drawbacks. Considerable skill and professional judgement are needed in formulating the decision trees that are a crucial part of the process. Croskerry (2005) showed that in medical specialties where decisions need to be routinely made in situations characterized by uncertainty, decision theory plays a negligible role. This was supported by Loftus (2006), who found that the health professionals in his study did not calculate medical decisions but articulated arguments in order to persuade patients, colleagues and themselves of a correct decision. It can be argued that a medical decision approach is useful for studying the optimal decisions for populations of patients, but has little place in the reality of clinical practice.

INTERPRETIVE RESEARCH APPROACHES

A recent alternative feature in the study of clinical reasoning has been the use of research approaches situated within the interpretive paradigm. Interpretive researchers have sought to study individuals within the context of their practice, thereby illuminating factors that individuals consider in their reasoning.

Our review of the history of clinical reasoning has thus far largely considered the history of clinical reasoning research as related to medicine. As health professions other than medicine have sought to understand the nature of their clinical practice and reasoning there has been an increasing use of interpretive research approaches. The use of these approaches has steadily increased since the early 1980s when Benner conducted seminal work into the nature of nursing expertise (Benner 1984) and later Gillette & Mattingly (1987) conducted a large scale ethnographic study of reasoning in occupational therapy. Jensen and associates (1992) added to the body of interpretive work by studying the nature of expertise in physiotherapy. These studies were followed by others that used interpretive approaches. However, much of this research has continued to focus on these same discipline areas (e.g. Titchen 2000 in nursing; Edwards et al 2004 and Resnik & Jensen 2003 in physiotherapy).

As suggested by the name, research within the interpretive paradigm seeks to interpret phenomena, in particular human phenomena (Higgs & Titchen 2000). Within the interpretive paradigm there is a major focus on preserving the context of the phenomenon and exploring its influence (Holman 1993). This is in contrast to the empirico-analytical paradigm where methods ‘work best when the context is defined, limited and perpetual’ (Holman 1993, p. 30). Within the interpretive paradigm, clinical reasoning may be viewed as a human activity that is socially, historically and culturally constructed. Leonard (1989, p. 46) explained that ‘to understand a person’s behaviour or expressions, one has to study the person in context, for it is only there that what an individual values and finds significant is visible’.

Interpretive approaches use methods of data collection such as interview and observation to record practitioners’ perspectives and descriptions of their clinical reasoning and associated actions. One advantage of these approaches over using paper-based cases is that it increases the likelihood that the research reveals practitioners’ reasoning as used in practice as opposed to their espoused theory (Argyris & Schön 1974) such as might be revealed with questions based on a hypothetical situation (Eraut 2005).

An important contribution of interpretive approaches to the study of clinical reasoning has been in revealing clinical reasoning as a complex, multidimensional, integrated, task- and context-dependent process. Researchers in fields such as medicine have traditionally taken narrow perspectives to understanding decision making and clinical reasoning; seeking to identify the cognitive process used by expert decision makers. Norman (2005), in a review of clinical reasoning literature in medicine, challenged this assumption, suggesting that there may not be a single representation of clinical reasoning expertise or a single correct way to solve a problem. He commented (p. 426): ‘the more one studies the clinical expert, the more one marvels at the complex and multidimensional components of knowledge and skill that she or he brings to bear on the problem, and the amazing adaptability she or he must possess to achieve the goal of effective care’. Interpretive approaches are grounded in a philosophical stance within which multiple interpretations of reality can exist. This philosophical stance results in the understanding of clinical reasoning pursued as a broad complex notion with multiple possible dimensions, and less in the realm of a single understanding to be discovered and tested.

The complexity of clinical reasoning revealed through interpretive approaches is evident in the findings of Smith (2006). Studying decision making by physiotherapists in acute care settings, she found that it was dependent upon the nature and complexity of the decision-making task, the attributes of the decision maker and the context in which the decisions were made. Further, Smith found that practitioners required complex cognitive, social, emotional and reflexive capabilities to integrate the multiple factors involved in clinical reasoning. Such a broad and dependent perspective would have been unobtainable with an approach that tested assumptions about the nature of factors affecting decision making, or viewed individuals apart from the contexts in which their decisions were made.

Further examples from interpretive approaches to the study of clinical reasoning reveal that in addition to diagnostic reasoning (which has been the predominant focus of medical research), practitioners engage in forms of reasoning such as narrative reasoning, reasoning about procedure, interactive reasoning, collaborative reasoning, reasoning about teaching, predictive reasoning, and ethical reasoning (Edwards et al 2004). In physiotherapy, broad dimensions of practice and reasoning have been identified, such as the individualized nature of care and expertise where the patient is the centre of decision making (e.g. Jensen et al 1992) and practice being characterized by reflexivity, contextual and task specificity and professional specificity of action (e.g. Beeston & Simons 1996, Jensen et al 2000, Resnik & Jensen 2003). Interpretive approaches have also revealed that clinical reasoning by individuals in acute care settings is socially and culturally determined and supported (Jette et al 2003).

The most important contribution of interpretive approaches to practice is in representing clinical reasoning as it occurs in real contexts. Therefore educational processes based on these approaches should result in novice practitioners who are better prepared for the reality of practice. This could avert the situation where novices acquire acontextual cognitive processes and conceptual frameworks which then have to be contextualized at the commencement of practice, with limited structured guidance and feedback as to how this is best achieved.

The contextualization of reasoning also has important implications for the current emphasis on EBP. The multidimensional understanding of clinical reasoning revealed by interpretive approaches suggests that the integration of evidence-based practice requires practitioners to balance EBP against other complex and at times competing influences on clinical reasoning. Much of the research produced and published under the rubric of EBP occurs with little reference to the context and broader factors that impact on its consumption by healthcare professionals (Rothstein 2004).

CONCLUSION

The history of clinical reasoning has resulted in a legacy of understanding that extends from discrete aspects of clinical reasoning, such as the use of hypothetico-deductive reasoning as a component in diagnostic decision making, through to representations of clinical reasoning as a multidimensional, complex phenomenon. Although we have argued for the advantages to be gained from interpretive approaches to the study of clinical reasoning it would be inappropriate to urge the exclusive use of these methods at the expense of approaches used in the empirico-analytical paradigm. The desired approach to the study of clinical reasoning is dependent upon the nature of the research question. When we seek to explore, describe and theorize about clinical reasoning as it occurs in the reality of practice, then interpretive approaches can be advocated as the approach of choice. When we seek to limit, control, test and compare aspects of reasoning this may be better achieved with experimental approaches. The combined use of different approaches to the study of clinical reasoning offers the challenge to bring the study of clinical reasoning out of paper-based cases which are acontextual into the realm of real practice.

As we saw with behaviourism, its limitations mean that it has largely been abandoned, but behaviourism has left us with a legacy of ideas that are still considered important and useful in medical education. A critical approach should be able to identify the difference between insights that are genuinely useful and those that are restricted to the philosophical assumptions of a particular field. For example, some of the insights of cognitivism, such as the use of the hypothetic-deductive method in clinical reasoning, seem to be robust findings, whereas the validity of the purported cognitive structures such as schemas and scripts is more questionable.

Our interpretation of this situation is that we are in a time of paradigm shift as described by Kuhn (1996). Some findings of cognitivism, such as the use of hypothetico-deductive reasoning with unfamiliar cases, may be subsumed by the newer interpretive approaches. However, there are fundamental conceptual differences between the older, more reductionist approaches and the newer interpretive approaches, and only time will reveal which paradigms prove to be more acceptable.