Validation of diagnostic codes for Charcot-Marie-Tooth disease in the Danish National Patient Registry

Abstract

PurposeTo validate the diagnostic codes for Charcot–Marie–Tooth disease (CMT) in the Danish National Patient Registry (DNPR) using positive predictive value (PPV) as a measure of validity.Patients and methodsWe used the DNPR to identify all patients diagnosed with at least one primary CMT diagnosis at a specialized department in the Central Denmark Region during the period 1977–2012. From this population, we randomly selected 123 patients for the validation study. Medical files were reviewed and used as reference standard. We estimated the PPV of the CMT diagnoses and stratified the analysis according to age at diagnosis, gender, and calendar time.ResultsIn the DNPR, 275 patients were identified. We were able to retrieve 96 medical files from the random sample of 123 patients, and 85 CMT diagnoses were confirmed. The average age at diagnosis was 42.5 years, and 34% were female. The PPV was 88.5% (95% confidence interval: 80.4–94.1).ConclusionThe CMT diagnoses in the DNPR have high validity. The DNPR can be used as a data source for epidemiologic research on CMT.

Charcot-Marie-Tooth disease in Denmark: a nationwide register-based study of mortality, prevalence and incidence

“… 8 We have previously reported a high validity of the CMT diagnoses, supporting the use of the DNPR in epidemiological research on CMT. 9 However, the CMT population in our study is not complete, as the DNPR only covers patients with hospital contact since 1977. Patients with milder signs and symptoms, or patients to whom CMT is already a well-known part of their family history, might never be referred to a hospital department.…”

“… 8 In a previous study, the positive predictive value (PPV) of the CMT diagnoses in the DNPR was reported as 88.5%. 9 …”

“…A similar approach was used in the validation study described above. 9 A flow chart of the selection process is shown in figure 1 .…”

“… 8 In a previous study, we found a high validity of the CMT diagnoses in the DNPR, thus supporting the use of the DNPR in epidemiological research on CMT. 9 …”

Doença de Charcot-Marie-Tooth ligado ao X em crianças: série de casos tipo 1 de pacientes do HC-FMRP

“…Achados de pé cavo e dedos em martelo são frequentes, observados em mais de dois terços dos casos. Foram propostos sete critérios para o diagnóstico clínico (De Jonghe & Timmerman, 1997;Haites, Nelis, Van Broeckhoven, 1998), sendo que para a validação diagnóstica em pacientes dinamarqueses (Vaeth et al, 2016), foram considerados pelo menos um dos três primeiros e pelo menos quatro dos sete:…”