Henk Lamberts

The coming of age of ICPC: celebrating the 21st birthday of the International Classification of Primary Care

The International Classification of Primary Care (ICPC) has, since its introduction in 1987, been quite successful. Now in its second revised version, it has been translated in 22 languages, accepted by the World Health Organization (WHO) as a member of the Family of International Classifications, and is being widely used both in routine daily practice and in research. In this contribution, it is explained that ICPC was designed as a theoretical classification, and that it has especially great potential when used (1) supported by the ICPC2/ICD10 Thesaurus, (2) in sufficiently large studies to allow all classes to be observed often enough to provide reliable data, and (3) in studies based on data on episodes of care, rather than encounter data only. Under these conditions, the likelihood ratios of symptoms given a diagnosis, and of co-morbidity become available, which define the clinical content of family practice.

Characterizing breast symptoms in family practice.

PURPOSE The frequency and outcome of breast symptoms have not been well characterized in primary care settings. To enhance and inform physician practice, this study aims to establish the proportion of visits and resultant diagnoses by age by examining longitudinal data on breast-related reasons for encounter. METHODS We used data from a prospective longitudinal sample of patients seeking care in Dutch family physician offices between 1985 and 2003 to provide routine family practice data on breast symptoms as the reason for encounter; all visits were coded using the International Classification of Primary Care. Data on breast symptom prevalence are based upon 84,285 active female patients and 367,834 total encounters. RESULTS Overall breast symptoms were reported in about 3% of all visits by female patients (29.7 per 1,000 active female patients per year); breast pain and breast mass were the most common breast-related complaints. Breast symptom complaints were highest among women aged 25 to 44 years (48 of 1,000) and among women aged 65 years and older (33 per 1,000). Of the women complaining of breast symptoms, 81 (3.2%) had breast cancer diagnosed. Breast mass had a markedly elevated positive likelihood ratio for breast cancer (15.04; 95% confidence interval, 11.74–19.28). CONCLUSIONS As expected, of patients with breast symptoms only a small subset was subsequently given a diagnosis of breast cancer (3.2%); however, the presence of a breast mass was associated with an elevated likelihood of breast cancer. These data illustrate the use of systematic data collection and classification from primary care offices to extract information regarding disease symptoms and diagnoses.

Developing an Appropriate EPR System for the Greek Primary Care Setting

The creation of an electronic patient record (EPR) system with a user-friendly interface based on the concept of the episode of care was considered an urgent priority in the present Greek context, where a Health Care Reform program is in progress. This paper reports the procedures of developing an EPR system, and outlines some of its essentials and key issues. We performed a systematic review and analyzed the perceptions and patterns of use of existing EPR systems among Greek general practitioners. On the basis of this analysis, Transhis was selected using defined criteria for appropriateness, efficiency, and feasibility for general practice as a prototype, for creating a Windows-based EPR system using the International Classification of Primary Care (ICPC-2) and International Classification of Diseases (ICD-10) as classifications. The new EPR system seems appropriate for use within the current Greek primary care setting. Further studies are required for its evaluation.

The core of computer based patient records in family practice: episodes of care classified with ICPC

A central element in the definition of primary care is that primary care clinicians address the large majority of personal health care needs of their patients. As a consequence, they should document data on these health care needs reliably and continuously. To establish whether this occurs, the episode of care is the most appropriate unit of assessment: a health problem from its first encounter with a health care provider until the completion of the last encounter for it. An episode of care is distinguished from episodes of disease and of illness. The episode of care as an epidemiological concept for the calculation of rates has evolved into a central element of a computer based record. Episode oriented data classified with the International Classification of Primary Care (ICPC), and specified with ICD-10 as a nomenclature are especially suitable as the core of a generic patient record in family practice. ICPC has been available to the family medicine community for well over a decade as the main ordering principle of its domain. The basic structure of an encounter (within the string of encounters which together form an episode of care) distinguishes reasons for encounter, diagnoses and diagnostic and therapeutic interventions. In this article, a more refined structure of encounters is proposed for a more precise documentation of episodes of care in a computer based patient record. The conversion structure between ICPC and ICD-10 allows both a high level of specificity in the patients problem list and optimal communication with specialists who contribute to the episodes of care for which the documentation is the primary care providers responsibility.

The classification of mental disorders in primary care : A guide through a difficult terrain

Background: Primary care physicians traditionally have a strong interest in the mental health of their patients. Three classification systems are available for them to diagnose, label, and classify mental disorders: 1) The ICD-10 approach with three options, 2) The DSM-IV approach with two options, and 3) the ICPC approach with two options. This article lists important similarities and differences between the systems to help potential users choose the option that best meets their needs. Methods: Definitions for depressive disorder, anxiety disorder, and somatization disorder are compared on five characteristics of classification: 1. the domain, 2. the scope, 3. the nature of the definitions, 4. focus on episodes of care, and 5. clinical guidelines. Results: Primary care physicians and psychiatrists have different perspectives, reflected in different classifications. Each system has specific possibilities and limitations with regard to the diagnosis of mental disorders. For common mental disorders it is possible, however, to choose codes from one system while maintaining compatibility with the other two. Comparability as to the diagnostic content of the different classes, however, is more difficult to establish. The available classification systems give both primary care physicians and psychiatrists options to diagnose, label, and to classify mental disorders from their own perspective, but once a system has been chosen the clinical comparability of a patient with the same diagnosis in other systems is limited. Conclusion: Compatibility among systems can be optimized by strictly following a number of rules. The conversion between ICPC and ICD-10 (and consequently DSM-IV) allows simultaneous use of ICPC and ICD-10 as a classification and DSM-IV as the standard nomenclature. This is of particular interest for computer based patient records in primary care. The clinical comparability of the same diagnosis in different systems however is limited by the characteristics of the different system.

An international comparative family medicine study of the Transition Project data from the Netherlands, Malta, Japan and Serbia. An analysis of diagnostic odds ratios aggregated across age bands, years of observation and individual practices

INTRODUCTION This is a study of the process of diagnosis in family medicine (FM) in four practice populations from the Netherlands, Malta, Serbia and Japan. Diagnostic odds ratios (ORs) for common reasons for encounter (RfEs) and episode titles are used to study the process of diagnosis in international FM and to test the assumption that data can be aggregated across different age bands, practices and years of observation. METHODOLOGY Participating family doctors (FDs) recorded details of all their patient contacts in an episode of care (EoC) structure using the International Classification of Primary Care (ICPC). RfEs presented by the patient and the diagnostic labels (EoC titles) recorded for each encounter were classified with ICPC. The relationships between RfEs and episode titles were expressed as ORs using Bayesian probability analysis to calculate the posterior (post-test) odds of an episode title given an RfE, at the start of a new EoC. RESULTS The distributions of diagnostic ORs from the four population databases are tabled across age groups, years of observation and practices. CONCLUSIONS There is a lot of congruence in diagnostic process and concepts between populations, across age groups, years of observation and FD practices, despite differences in the strength of such diagnostic associations. There is particularly little variability of diagnostic ORs across years of observation and between individual FD practices. Given our findings, it makes sense to aggregate diagnostic data from different FD practices and years of observation. Our findings support the existence of common core diagnostic concepts in international FM.

Once tired, always tired? Limitations in function over time of tired patients in Dutch general practice

Objective: To gain insight into limitations in function over time of general-practice patients who presented and were diagnosed with “tiredness”. Methods: In a routine family-practice electronic register based on use of the International Classification of Primary Care (ICPC), 684 patients were identified who presented (in 1997 or 1998) with the complaint tiredness, who were given the same symptom diagnosis, and who still had this diagnosis on 1 August 1999. A questionnaire (WONCA/COOP charts, HAD Scale, recent medical care, tiredness and attribution) was sent to these 684 “cases” and 858 controls. In a logistic regression analysis (16 dichotomous variables), we constructed five models for optimizing sensitivity and specificity for the detection of patients with an episode of care for “tiredness”. Results: We received 385 fully completed questionnaires of cases, on average 19 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 months after the start of their episode of care for “tiredness”. The results of the 1997 and 1998 cases were similar. Cases did considerably worse than did the 385 optimally matched controls: e.g., seriously limited by tiredness: 52% of cases vs 32% of controls; poor overall health: 35% of cases vs 20% of controls; HAD Scale scores indicating anxiety or depression: about 20% of cases vs about 10% of controls. Highest sensitivity (70%) was reached by including poor overall health, recent medical care and HAD Scale depression score >10 in the model; and highest specificity (65%) by including poor overall health and a HAD Scale anxiety score >7. Conclusion: Patients who present with tiredness and receive the same diagnosis have a high probability of suffering from substantial limitations in function in the years following diagnosis. Their limitations are more serious than those of controls, but no indication is found for a specific limitation. The indicators are strongly related and concentrate around “poor overall health”.

Empowerment of patients seeking information about medical interventions

Objectives: To examine the use of free access second opinion. To assess why patients ask for a second opinion from a physician other than their own general practitioner or specialist when they have to decide about a medical intervention, what patients ask, how patients decide afterwards and how they evaluate the second opinion.Methods: 200 consecutive patients asking for free access second opinion were prospectively studied. The content of the second-opinion consultation was documented in detail. Three months later, the patients were interviewed about what in fact they decided to do and whether they considered the second opinion useful.Results: The 200 patients seeking second opinion presented 219 episodes, which were categorised in three types: in the premedical phase (n=41);when treated by their general practitioners (n=84);when treated by specialists (n=94).Episodes in the premedical phase and in primary care were mainly fatigue and pain related. Half of the secondary care episodes belonged to the spec...

Generic research in general practice

This paper is an adapted version of a lecture given at the ‘Referatendag’ (a joint meeting of researchers from the Netherlands and the United Kingdom), Amsterdam, the Netherlands, 1996.

The Use and Relevance of the International Classification of Primary Care (ICPC) in Structuring Patient Information

Information systems and health statistics deal with data which have been ordered and received a name, so that they can be counted. What has no name, cannot be counted and consequently has no impact. ICPC, together with its manual provides the best available tool to order and to name essential elements of primary care. It offers a widely tested, comprehensive classification system which can be used in three modes: as a Reason for Encounter classification as a Diagnostic classification as a Process classification.