Coverage and accuracy of diagnosis of cruciate ligament injury in the Finnish National Hospital Discharge Register

doi:10.1016/j.injury.2008.05.007

Injury

Volume 39, Issue 12, December 2008, Pages 1373-1376

https://doi.org/10.1016/j.injury.2008.05.007 Get rights and content

Summary

Introduction

Routinely collected hospital discharge data are a valuable and widely used source of information when assessing the incidence of sports and other injuries in epidemiological studies. However, in order to ensure the usefulness of a hospital discharge register for scientific purposes, the coverage and accuracy of the database should be evaluated. In this study, cruciate ligament rupture was used to assess the coverage and accuracy of the Finnish National Hospital Discharge Register (NHDR).

Materials and methods

The coverage of the diagnosis of cruciate ligament injury in the NHDR was examined by comparing patients with a confirmed cruciate ligament injury in the arthroscopy register of the Finnish Central Military Hospital (N = 262) to their register data in the NHDR. To assess the accuracy of this diagnosis in the NHDR, the original medical reports including magnetic resonance imaging (MRI) and arthroscopy files were reviewed.

Results

Of the above noted 262 conscripts with a confirmed cruciate ligament injury, 241 were found to be correctly coded in the NHDR (register coverage 92%). Concerning register accuracy, of the 217 patients having cruciate ligament injury as the main or secondary diagnosis in the NHDR, 194 were confirmed to have this injury as verified by MRI or arthroscopy of the knee (register accuracy 89%).

Conclusions

Our results showed that the coverage and accuracy of diagnosis registration of a cruciate ligament injury of the knee in the Finnish NHDR are very good. Further multi-centre studies are needed to confirm our findings.

Introduction

Routinely collected hospital discharge data are a valuable and widely used source of information when assessing the incidence of sports and other injuries in epidemiological studies.[4], [7] However, in order to ensure the usefulness of a hospital discharge register for scientific purposes, the coverage and accuracy of the database should be evaluated.

Studies investigating the coverage and accuracy of hospital discharge registers are scarce. In Finland, the studies have been focused mainly on coronary heart disease and the results have been good. ⁹ In addition, a small number of reports on the accuracy of registered injury diagnoses have been published showing for example that the accuracy of pelvic and hip fracture diagnoses ranges from 95 to 98%.[3], [5], [6], [10] However, the coverage of injuries in the Finnish National Hospital Discharge Register (NHDR) has not previously been well assessed.

A cruciate ligament tear is a common, often sports-induced, serious injury of the knee.² The existing epidemiological data have usually described injuries to the anterior cruciate ligament (ACL) in specific athlete populations using hospital registers to identify the injury cases.[1], [2], [11]

In the Finnish Defence Forces, the examination and treatment of cruciate ligament injuries were concentrated in one hospital, the Central Military Hospital, Helsinki, Finland. In this hospital the diagnosis of a cruciate ligament injury of the knee was at the time of this study systematically based on magnetic resonance imaging (MRI) and arthroscopy. Furthermore, due to the health requirements of Finnish military service, all conscripts at risk of service interruption due to a major knee complaint are referred to the Central Military Hospital. This protocol thus allows reliable evaluation of the coverage and accuracy of the injury diagnosis in the Finnish NHDR, (the register is not affiliated with the Finnish Defence Forces).

We assessed the coverage and accuracy of diagnosis registration of cruciate ligament injury of the knee in the Finnish NHDR by examining the patient files in the Central Military Hospital between 1997 and 2002.

Section snippets

Material and methods

In this study, we first retrospectively searched all patients who had been hospitalised at the Central Military Hospital, Helsinki, Finland between 1997 and 2002 with a primary or secondary diagnosis of a cruciate ligament injury from the Finnish National Hospital Discharge Register. This register is a statutory, computerised database covering the entire population of the country.⁸ For patient identification we used the International Classification of Diseases (the Tenth revision, ICD-10) code

Coverage of injury diagnosis in the Finnish NHDR

According to the arthroscopy register of the Central Military Hospital of Finland, a total of 262 conscripts had an arthroscopically confirmed diagnosis of a cruciate ligament injury of the knee in 1997–2002. Of these 262 cases, 241 were correctly coded in the Finnish NHDR (register coverage 92%).

Accuracy of injury diagnoses in the Finnish NHDR

In the NHDR, the diagnosis code S83.5 was used on altogether 272 persons, including 217 patients whose original medical records were available and provided for the review process of this study.

Discussion

Hospital discharge registers are a widely used resource in epidemiological research to describe injury or disease incidence. The registration coverage and accuracy are, however, poorly studied. In this study, we evaluated the quality of cruciate ligament injury diagnosis in the Finnish NHDR during 1997–2002. Our study revealed that both the coverage of the injury diagnosis registration (92%) and the accuracy (89%) of the registered diagnoses were very good in the NHDR.

As far as we know, no

Conclusions

In conclusion, the coverage (92%) and accuracy (89%) of diagnosis of cruciate ligament injury of the knee in the Finnish National Hospital Discharge Register are very good. For epidemiological purposes, cruciate ligament injuries can thus be reliably assessed from this register.

Acknowledgement

We thank Mrs. Marja Vajaranta for language editing.

References (11)

V.M. Mattila et al.
Hospitalisation for injuries among Finnish conscripts in 1990–1999
Accid Anal Prev
(2006)
J.M. Bjordal et al.
Epidemiology of anterior cruciate ligament injuries in soccer
Am J Sports Med
(1997)
D.E. Gwinn et al.
The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy
Am J Sports Med
(2000)
R. Honkanen
Hospitalizations due to injuries in Finland in 1980
Kuopio
(1990)
P. Kannus et al.
Fall-induced injuries and deaths among older adults
JAMA
(1999)

There are more references available in the full text version of this article.

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Coverage and accuracy of diagnosis of cruciate ligament injury in the Finnish National Hospital Discharge Register

Summary

Introduction

Materials and methods

Results

Conclusions

Introduction

Section snippets

Material and methods

Coverage of injury diagnosis in the Finnish NHDR

Accuracy of injury diagnoses in the Finnish NHDR

Discussion

Conclusions

Acknowledgement

Accid Anal Prev

Epidemiology of anterior cruciate ligament injuries in soccer

Am J Sports Med

The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy

Am J Sports Med

Hospitalizations due to injuries in Finland in 1980

Kuopio

Fall-induced injuries and deaths among older adults

JAMA