An international comparative family medicine study of the Transition Project data from the Netherlands, Malta and Serbia. Is family medicine an international discipline? Comparing diagnostic odds ratios across populations.

INTRODUCTION: This is an international study of the epidemiology of family medicine (FM) in three practice populations from the Netherlands, Malta and Serbia. Diagnostic associations between common reasons for encounter (RfEs) and episodes titles are compared and similarities and differences are described and analysed. 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 episode titles (diagnostic labels of EoCs) were classified with ICPC. The relationships between RfEs and episode titles were studied with Bayesian methods. RESULTS: Distributions of diagnostic odds ratios (ORs) from the three population databases are presented and compared. CONCLUSIONS: ICPC, the RfE and the EoC data model are appropriate tools to study the process of diagnosis in FM. Distributions of diagnostic associations between RfEs and episode titles in the Transition Project international populations show remarkable similarities and congruencies in the process of diagnosis from both the RfE and the episode title perspectives. The congruence of diagnostic associations between populations supports the use of such data from one population to inform diagnostic decisions in another. Differences in the magnitude of such diagnostic associations are significant, and population-specific data are therefore desirable. We propose that both an international (common) and a local (health care system specific) content of FM exist and that the empirical distributions of diagnostic associations presented in this paper are a reflection of both these effects. We also observed that the frequency of exposure to such diagnostic challenges had a strong effect on the confidence intervals of diagnostic ORs reflecting these diagnostic associations. We propose that this constitutes evidence that expertise in FM is associated with frequency of exposure to diagnostic challenges.

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.

An international comparative family medicine study of the Transition Project data from the Netherlands, Malta and Serbia. Is family medicine an international discipline? Comparing incidence and prevalence rates of reasons for encounter and diagnostic titles of episodes of care across populations.

INTRODUCTION: This is a study of the epidemiology of family medicine (FM) in three practice populations from the Netherlands, Malta and Serbia. Incidence and prevalence rates, especially of reasons for encounter (RfEs) and episode labels, are compared. METHODOLOGY: Participating family doctors (FDs) recorded details of all their patient contacts in an episode of care (EoC) structure using electronic patient records based on the International Classification of Primary Care (ICPC), collecting data on all elements of the doctor-patient encounter. RfEs presented by the patient, all FD interventions and the diagnostic labels (EoCs labels) recorded for each encounter were classified with ICPC (ICPC-2-E in Malta and Serbia and ICPC-1 in the Netherlands). RESULTS: The content of family practice in the three population databases, incidence and prevalence rates of the common top 20 RfEs and EoCs in the three databases are given. CONCLUSIONS: Data that are collected with an episode-based model define incidence and prevalence rates much more precisely. Incidence and prevalence rates reflect the content of the doctor-patient encounter in FM but only from a superficial perspective. However, we found evidence of an international FM core content and a local FM content reflected by important similarities in such distributions. FM is a complex discipline, and the reduction of the content of a consultation into one or more medical diagnoses, ignoring the patient's RfE, is a coarse reduction, which lacks power to fully characterize a population's health care needs. In fact, RfE distributions seem to be more consistent between populations than distributions of EoCs are, in many respects.

Revisiting the concept of 'chronic disease' from the perspective of the episode of care model. Does the ratio of incidence to prevalence rate help us to define a problem as chronic?

BACKGROUND: This is a study of the epidemiology of acute and chronic episodes of care (EoCs) in the Transition Project in three countries. We studied the duration of EoCs for acute and chronic health problems and the relationship of incidence to prevalence rates for these EoCs. METHOD: The Transition Project databases collect data on all elements of the doctor-patient encounter in family medicine. Family doctors code these elements using the International Classification of Primary Care. We used the data from three practice populations to study the duration of EoCs and the ratio of incidence to prevalence for common health problems. RESULTS: We found that chronic health problems tended to have proportionately longer duration EoCs, as expected, but also a lower incidence to prevalence rate ratio than acute health problems. Thus, the incidence to prevalence index could be used to define a chronic condition as one with a low ratio, below a defined threshold. CONCLUSIONS: Chronic health problems tend to have longer duration EoCs, proportionately, across populations. This result is expected, but we found important similarities and differences which make defining a problem as chronic on the basis of time rather difficult. The ratio of incidence to prevalence rates has potential to categorise health problems into acute or chronic categories, at different ratio thresholds (such as 20, 30 or 50%). It seems to perform well in this study of three family practice populations, and is proposed to the scientific community for further evaluation.

The interpretation of the reasons for encounter 'cough' and 'sadness' in four international family medicine populations.

BACKGROUND: This is a study of the relationships between common reasons for encounter (RfEs) and common diagnoses (episode titles) within episodes of care (EoCs) in family practice populations in four countries. METHOD: Participating family doctors (FDs) recorded details of all their patient contacts in an EoC structure using the International Classification of Primary Care (ICPC), including RfEs presented by the patient, and the FDs' diagnostic labels. The relationships between RfEs and episode titles were studied using Bayesian methods. RESULTS: The RfE 'cough' is a strong, reliable predictor for the diagnoses 'cough' (a symptom diagnosis), 'acute bronchitis', 'URTI' and 'acute laryngitis/tracheitis' and a less strong, but reliable predictor for 'sinusitis', 'pneumonia', 'influenza', 'asthma', 'other viral diseases (NOS)', 'whooping cough', 'chronic bronchitis', 'wheezing' and 'phlegm'. The absence of cough is a weak but reliable predictor to exclude a diagnosis of 'cough', 'acute bronchitis' and 'tracheitis'. Its presence allows strong and reliable exclusion of the diagnoses 'gastroenteritis', 'no disease' and 'health promotion/prevention', and less strong exclusion of 'adverse effects of medication'. The RfE 'sadness' is a strong, reliable predictor for the diagnoses 'feeling sad/depressed' and 'depressive disorder'. It is a less strong, but reliable predictor of a diagnosis of 'acute stress reaction'. The absence of sadness (as a symptom) is a weak but reliable predictor to exclude the symptom diagnosis 'feeling sad/depressed'. Its presence does not support the exclusion of any diagnosis. CONCLUSIONS: We describe clinically and statistically significant diagnostic associations observed between the RfEs 'cough' and 'sadness', presenting as a new problem in family practice, and all the episode titles in ICPC.