Validity of Stroke Diagnosis on Hospital Discharge Records in Saskatchewan, Canada: Implications for Stroke Surveillance

Abstract

This study examines the validity of the diagnosis of stroke on hospital discharge records in Saskatchewan, Canada. In total, 1,494 records with a discharge diagnosis of ‘stroke’ or a ‘stroke-related condition’ were reviewed. The clinical algorithm of the 1980 USA National Survey of Stroke was considered the ‘gold standard’. The positive predictive value of a primary diagnosis of stroke in the tertiary-care hospitals was about 90%. In community hospitals the majority of stroke cases were coded as ICD9 436 in which the positive predictive value was 78%. The variation between regions would limit the use of hospital discharge data for stroke surveillance.

Secular Trends in the Survival of Patients with Laryngeal Carcinoma, 1995–2007

“…Diagnoses and procedures were determined using the codes in the International Classification of Diseases, 9th revision Whenever possible, we applied database codes that had been validated by chart review [22][23][24][25][26][27] . The databases were linked using unique encoded identifiers (encrypted Ontario health card numbers that are unique to each resident eligible for health care services paid by the government) available starting July 1991, after the assignment of new health card numbers in Ontario.…”

Examining Vertebrobasilar Artery Stroke in Two Canadian Provinces

“…6 This may explain the differences in the incidence rates with the American study. 1 The strength of our study is that the administrative database used in the analysis captures all discharge diagnoses for all residents of the 2 provinces.…”

“…In Canada, VBA may have been misclassified as another type of stroke because of the problems associated with accurately diagnosing this type of stroke. 6 A large increase in the annual incidence rate of VBA stroke was found in Saskatchewan and a smaller increase in Ontario after 1999. This increase subsequently dropped in 2002 for Ontario and in 2003 for Saskatchewan.…”

Developing workable research methods: lessons from a pilot study with vulnerable participants and complex assessments

“…In hindsight, some patients were excluded unnecessarily. The merits of clinical diagnosis of stroke have been debated as the validity of the resultant diagnosis can be variable (Liu et al, 1999). However, studies examining the reliability and validity of clinical classification of stroke suggest that clinical diagnosis may have an acceptable level of accuracy for recruitment to many studies (Smith et al, 2001;Parsons et al, 2009).…”