Helping Hands

An Introduction to Diagnostic Strategy and Clinical Reasoning

Caroline Rodgers, Richard Harrington

• Publisher: CRC Press
• Year: 2019
• ISBN:
  9780429825040
• Edition: 1
• Topic: Medizin
• Subtopic: Medizinische Theorie, Praxis & Referenz

This brand-new textbook introduces medical students, junior doctors, medical educators and allied health professionals to the vital skills of diagnostic strategy and clinical reasoning, both essential components of becoming an effective clinician. Taking the examination of the hands as a springboard – often the initial step in physical examination and from which a wealth of information can be gleaned – through real-life clinical cases readers are encouraged to refine their powers of observation and decision-making strategy.

Key features:

• Encourages a conscious approach to clinical reasoning – 'see' rather than just 'look'

• Develops an understanding of why all clinicians can be responsible for diagnostic mistakes and how, with a raised awareness, they can work towards avoiding error

• Outlines approaches that can be used when taking a history and when examining patients in any clinical setting

• Bundled e-book for use 'on the go' while the companion website provides additional materials for students and lecturers including self-assessment questions and teaching guidance

Outlining the process of formulating and refining an initial diagnosis, in using this book the medical student or junior doctor will develop a critical self-awareness of the strategies they employ in assessing patients, learn how to improve and enhance their skills, and feel enabled to craft an appropriate management plan.

1 Introduction

‘No teaching without a patient for a text.’¹

Diagnostic strategy and clinical reasoning are not usually part of the formal curriculum at medical school. Currently, there are few resources available that introduce medical students and junior doctors to this area.

This book will help you understand clinical reasoning: the process by which a clinician formulates and refines an initial diagnosis with a view to developing an appropriate management plan. By being conscious of your approach to clinical reasoning, you will be better able to develop your clinical skills and diagnostic aptitude. You will also develop an understanding of why on occasion all clinicians are responsible for diagnostic errors – and you will learn strategies to avoid such mistakes.

As a medical student or junior doctor, this book will help you develop a critical self-awareness of the strategies you employ in assessing patients. The first section addresses strategies that can be used when taking a history, and the second strategies used when examining patients. To illustrate the latter with ‘real life’ examples, we start with scenarios based on examination of the hands, which is often the initial step in physical evaluation. A patient’s hands can provide a wealth of information relevant to the diagnostic process. However, the strategies described are equally applicable to any part of the clinical examination.

This book will help you develop an understanding of the diagnostic approaches used by most experienced clinicians. By careful study of the illustrated cases, you will be encouraged to ‘see’ rather than just ‘look’ and to refine your powers of observation. In addition, we provide online resources that can be used for revision to help you learn topics in clinical medicine, and include a section on teaching clinical reasoning for medical educators.

The patients have been selected to demonstrate a spectrum of approaches used in clinical reasoning. They demonstrate the process of forming a diagnostic hypothesis including the intuitive spot diagnosis based on a single clinical cue, and more sophisticated pattern recognition. The more complex cases lead to a consideration of the various refinement strategies including restricted rule out, pattern fit recognition and deliberate reasoning.²

Whatever your stage of training, the following histories and illustrated key cases, combined with an introduction to the theory of clinical reasoning, will help advance your knowledge and clinical skills as well as develop a critical self-awareness of the diagnostic processes used by all clinicians. We hope you enjoy the clinical scenarios and learn from the process of studying them. We would like to thank the patients who kindly agreed to be photographed for the purposes of this book.

SUMMARY

• Examination of the hands is often the initial step in physical examination, and a wealth of information can be gleaned from the hands.
• This chapter introduces the main themes of the book – clinical reasoning, diagnostic strategy and bias leading to error.
• The structure of the book is described, which emphasises how strategies can be employed during history taking and examination.
• In addition, each chapter is accompanied by clinical cases that take a predominantly ‘serial cue’ approach.

REFERENCES

1 Bliss M, Osler W. A Life in Medicine. New York: Oxford University Press; 2007.

2 Heneghan C, Glasziou P, Thompson M, et al. Diagnostic strategies used in primary care. BMJ 2009;338:b946.

2 Clinical reasoning

Why it is important to study clinical reasoning

Diagnostic closure

How doctors think

Comparing system 1 thinking and system 2 thinking

Improving clinical reasoning

References

WHY IT IS IMPORTANT TO STUDY CLINICAL REASONING

Clinical reasoning is in broad terms the cognitive process underpinning the diagnosis and management of patients.¹ Diagnosis can be viewed as the ‘answer’ that one arrives at after a process of reasoning, often seen as a ‘diagnostic label’. Another important construct is to see diagnosis as a dynamic stepping stone and not an end point in the process of clinical reasoning.² Central to clinical reasoning is clinical decision making, which involves key critical thinking skills of:

• Hypothesis generation.
• Information processing and synthesis.
• Weighing up of evidence.
• Formulating a decision to be acted on.

Decision making uses a clinician’s knowledge and powers of metacognition: the ability to reflect, reason and refine (Figure 2.1).³

Fig. 2.1 The components of clinical reasoning (adapted from Himmerick³).

High-quality care and patient safety are the prime concerns for clinicians and patients alike. Optimal clinical decision making goes a very long way towards avoiding error (e.g. diagnostic failure or prescribing errors) and poor-quality care. Therefore, it is important that we try to understand the process of clinical reasoning and the ways in which we can improve it, rather than leaving it as a ‘black box’ (as clinical reasoning expert Croskerry phrases it).⁴

DIAGNOSTIC CLOSURE

It is important to recognise diagnosis as a shared process between health professionals and patients rather than the end point of the assimilation of information and pronouncement of ‘an answer’. Knowing when to stop in the process of clinical decision making (diagnostic closure) is a skill in itself and also the subject of research.⁵ When are we confident we have enough information to make a diagnosis? Do we need to request further tests or carry out a further examination? Also, it is important to remember that we should not accept without question the diagnostic closure of other clinicians if a patient’s signs and symptoms do not quite add up. We can revisit the diagnostic process and observe how a situation progresses.² Sometimes we have to acknowledge that we cannot always apply a diagnostic label to a situation and that we are unable to account for and resolve a patient’s complaint.

HOW DOCTORS THINK

Decision making is the bread and butter of a clinician’s work on a daily basis. Yet this skill is often neglected in the curricula of medical schools worldwide and there is a call for better understanding and training in diagnostics.⁶ There is a growing body of evidence to support the premise, that when diagnostic errors occur, it is often a failure not of knowledge but of the decision-making process.⁷ We are beginning to build up a picture of the cognitive processes behind clinicians’ clinical reasoning from research in both the laboratory and the clinical environment. With a better picture we can begin to develop and appraise strategies to improve reasoning and avoid error.

How clinicians might represent disease in their memories is under debate in the literature. Certainly, some representations are in the form of scenarios relating to previous patient encounters.⁸ Hence it is thought that each individual clinician builds up their own memory bank of patient ‘exemplars’ (case memories), cat...