Morbidity in primary care

Morbidity in Primary Care: Epidemiologic Data from Family Medicine Network uses Dutch general-practice records to examine symptoms, diagnoses, and their relationships. The first 2023 edition contains a methods section and twenty-seven condition-focused chapters, drawing on data presented for 2014–2021.

How to study this book

Read the methods before comparing conditions. Record the population, period, age and sex grouping, denominator, and whether a figure describes incidence, prevalence, an encounter, or an episode. Separate the presenting reason for encounter from the eventual episode diagnosis. Use linked data cautiously because the website may have changed since the printed edition.

Chapter-wise explanations and study tasks

Methods — Interpreting FaMe-Net Data

The methods explain longitudinal registration, episodes of care, reasons for encounter, diagnostic labels, classifications, and interventions. One person may have repeated contacts within one episode, and the diagnostic label can change as knowledge develops. Distinguish those units before interpreting counts or associations.

Study task: Create a fictional sequence of contacts and label reasons for encounter, encounter diagnoses, and the evolving episode diagnosis; specify the denominator for a rate.

Varicella-Zoster Virus Infection: Chickenpox (A72)

The chapter places chickenpox within registered primary-care morbidity. Read the age distribution and presenting reasons alongside the case definition and observation period. A consultation-based pattern is not automatically the pattern of all infections in a community.

Study task: Extract one age-related comparison and explain what the registered population and consultation context allow you to conclude.

Gastrointestinal Infection (D73)

The gastrointestinal-infection entry connects presentations with a primary-care diagnostic category. Consider how symptoms, subsequent encounters, and episode classification affect the figures. Avoid equating every gastrointestinal complaint with this particular episode diagnosis.

Study task: Map one presenting complaint to the chapter's diagnostic context and list alternative interpretations that the dataset alone cannot settle.

Colorectal Cancer (D75)

The colorectal-cancer chapter invites examination of initial presentations and eventual diagnoses. Distinguish the distribution of presenting complaints among diagnosed cases from the probability of cancer among people presenting with a complaint. Those reverse questions require different denominators.

Study task: Write both conditional questions explicitly and identify which source figure, if any, answers each.

Blepharitis, Hordeolum, and Chalazion (F72)

Several related eyelid conditions share the entry's category. Read the scope of that grouping before interpreting an aggregate figure as evidence about one specific condition. Compare the chapter's descriptions with what the coding scheme can distinguish.

Study task: Create a category-boundary note showing what the combined code includes and what cannot be inferred about its individual components.

External Otitis (H70)

External otitis is examined through its primary-care presentations and recorded frequency. Keep this category separate from middle-ear conditions when comparing nearby chapters. Differences in attendance and classification can affect apparent contrasts.

Study task: Compare the denominators and age groupings used here and in the acute-otitis-media entry before comparing their rates.

Acute Otitis Media (H71)

The acute-otitis-media entry provides another example of how a diagnosis is represented in longitudinal practice records. Consider age composition and episode definitions when reading frequency. A repeated encounter need not represent a new disease episode.

Study task: Use a fictional repeat visit to explain why encounter counts and incident episodes could differ.

Ischaemic Heart Disease (K74, K75, K76)

This chapter brings several ischaemic-heart-disease codes into one discussion. Examine what is combined and how that affects incidence, prevalence, and presentation comparisons. A broad category can be useful while concealing differences among its component diagnoses.

Study task: Prepare a code-and-measure table and explain one limitation of interpreting the combined category.

Heart Failure (K77)

Heart failure illustrates a chronic condition whose recorded prevalence and new diagnoses answer different questions. Link the chapter's figures with age distribution and continuing care. Do not treat a prevalence pattern as a direct estimate of future risk for an individual.

Study task: Compare one incidence and one prevalence measure and explain why they need not move together.

Parkinson Disease and Parkinsonism (N87)

The grouped neurological entry requires attention to diagnostic scope and the distinction between syndromic and more specific labels. Longitudinal records may change as information develops. Explain what the registered category supports rather than assigning a precise aetiology from its code alone.

Study task: Write a category interpretation with included labels, observation period, and a limitation on disease-specific conclusions.

Migraine (N89)

The migraine chapter connects a recurring condition with primary-care presentation and registration. Distinguish the number of people with a recorded diagnosis from the number of attacks or visits. Consider who is likely to consult and receive the label.

Study task: Explain three different quantities—people, episodes, and encounters—and identify which the selected source measure describes.

Sleep Disturbance (P06)

A symptom-level entry shows how the dataset includes problems that do not necessarily begin as a specific disease diagnosis. Read the presenting concern and episode label separately. The code does not establish one cause for every recorded sleep problem.

Study task: Construct a fictional sleep-related presentation and explain how an episode label might change without altering the original reason for encounter.

Dementia (P70)

The dementia chapter supports study of registered morbidity in a condition associated with continuing care and changing needs. Examine how age structure and observation length affect comparisons. The primary-care label is not a complete record of cognitive assessment or disease subtype.

Study task: Interpret a selected age-stratified figure and list information needed before comparing it with another population.

Depression (P76)

The depression entry connects recorded diagnosis, presenting concerns, and primary-care management context. Separate service use and registration from unobserved community morbidity. Symptoms recorded at presentation and a final diagnosis should not be treated as interchangeable.

Study task: Develop a short limitations statement for using the chapter's figures to describe depression outside the participating practices.

Mental Exhaustion and Burnout (P78)

The mental-exhaustion category highlights the importance of terminology and classification. Compare what the entry includes with broader everyday use of burnout. Social and practice contexts can affect presentation and labelling, so a code-based comparison needs explicit scope.

Study task: Define the category using the chapter and identify two reasons that rates from differently defined sources might not be comparable.

Attention Deficit Hyperactivity Disorder (P81)

The ADHD entry can be examined through age, registered diagnoses, and the longitudinal nature of primary care. Distinguish a new record of a diagnosis from an assumption about when the underlying condition first began. A code does not supply an individual diagnostic assessment.

Study task: Write a comparison of diagnosis-registration timing and condition onset, explaining what the data can and cannot establish.

Rhinosinusitis (R75)

Rhinosinusitis illustrates interpretation of a respiratory diagnosis among overlapping presenting complaints. Keep the category and episode definition visible when comparing it with other respiratory entries. Registered diagnosis does not mean every similar symptom belongs to that category.

Study task: Create a presentation-to-diagnosis diagram and mark where information beyond the initial complaint is needed.

Tonsillitis (R76)

The tonsillitis entry provides another setting for comparing symptoms, diagnoses, and episode frequency. Interpret age patterns and consultations within the practices' population and coding conventions. A treatment description in the source is not itself current individual prescribing advice.

Study task: Select a source comparison and describe its population, denominator, time frame, and one limit to generalization.

COPD (R95)

COPD is presented within the network's chronic-disease records. Incidence, prevalence, age composition, and continuing contacts describe different aspects of recorded burden. Comparisons require attention to case identification and the practice-based setting.

Study task: Build a table separating new diagnoses, existing registered cases, and care encounters, and explain why each measures something different.

Asthma (R96)

The asthma chapter allows comparison of another respiratory condition across demographic and encounter patterns. Avoid assuming that similarly named diagnoses or figures from other settings use the same definitions. Explain how the recorded population shapes interpretation.

Study task: Compare asthma and COPD using matched source measures, then identify which differences require further contextual explanation.

Allergic Rhinitis (R97)

The allergic-rhinitis entry combines a condition definition with primary-care presentation. Distinguish observed attendance from all symptoms experienced outside consultations. If comparing time patterns, confirm the source's interval and measurement before attributing change to a cause.

Study task: Prepare a note separating recorded disease, presenting symptoms, and unobserved community experience.

Naevus (S82)

The naevus chapter demonstrates the importance of distinguishing a presenting skin concern from the diagnostic category ultimately assigned. The entry's code should not be interpreted as an individual assessment of malignancy risk. Examine how the chapter organizes reasons for encounter.

Study task: Trace a fictional skin concern through presentation and classification and identify what cannot be concluded from the code alone.

Atopic Dermatitis: Eczema (S87)

The eczema entry illustrates a condition with continuing or recurring care needs. Separate people living with a registered diagnosis from visits about symptoms or management. Interpret age comparisons against the study population rather than infer a universal course.

Study task: Compare person-based and encounter-based descriptions of eczema and explain how recurrent visits affect one but not necessarily the other.

Type 2 Diabetes Mellitus (T90)

The diabetes chapter connects a long-term diagnosis with primary-care epidemiology. Recorded prevalence reflects case accumulation and population context as well as new diagnosis. The entry does not by itself estimate complication risk or the effect of a particular treatment.

Study task: Explain how a stable incidence and changing prevalence could coexist, identifying additional information required to assess the explanation.

Urinary Tract Infection (U71)

The urinary-tract-infection entry provides a setting for studying episodes, repeat contacts, and demographic comparisons. Distinguish a new episode from follow-up within an existing one. Interpretation depends on the chapter's diagnostic scope and source definitions.

Study task: Create two fictional consultation timelines and explain when they might represent one episode versus more than one.

Chronic Renal Failure (U99)

The renal entry uses the chapter's category and coding context, which need careful comparison with other sources. Terminology and classification can differ from modern clinical staging frameworks. Use the text's definitions rather than assume that a broad code supplies detailed disease severity.

Study task: Write a coding-comparability note identifying the category, measure, and missing detail needed for comparison with a staged renal dataset.

Subfertility (W15 / Y10)

The subfertility chapter connects female and male codes with a concern that can involve more than one person. Clarify the unit counted and avoid treating two linked records as automatically independent cases. Presentation and registration are distinct from all people experiencing difficulty conceiving.

Study task: Explain the person, couple, encounter, and episode units that might be relevant and identify which the chosen source measure uses.

Breast Cancer (X76)

The breast-cancer entry returns to the relationship between presenting concerns and a final diagnosis. Separate an association within registered cases from a screening-performance measure or an individual's probability. Keep age and population context explicit.

Study task: Analyze one presentation figure and explain why it cannot be converted into a predictive value without an appropriate denominator.

Applied assignment

Compare three condition chapters using a common extraction sheet for population, period, category, numerator, denominator, and measure. Add a fictional episode-of-care timeline and a limitations section covering reverse conditional questions, consultation patterns, and generalizability.

Suggested reading plan

Read Methods first, study one acute and one chronic condition to practise definitions, then compare related chapters using matched measures. Finish with cancer and symptom-level entries to examine presentation-to-diagnosis relationships.

Questions for reflection

• Are you counting people, episodes, or encounters?
• Does the denominator answer the question being asked?
• What changes when these Dutch practice data are applied elsewhere?

Edition and source notes

Based on the 2023 first edition edited by Hilde Luijks, Floris van de Laar, and Henk Schers. Its twenty-seven condition chapters and Methods are covered. The printed data concern 2014–2021; linked online figures may be updated. The guide supports epidemiological interpretation, not diagnosis or treatment selection for an individual.

Consult the official source and full text.