Table 7 Characteristics of economic burden studies included in the review

Retrospective cohort studies

Sadatsafavi et al. 2010 [10] 1996 - 2000

Administrative healthcare data

Determine direct medical costs of asthma-related healthcare in British Columbia

Aged 5 to 55 years

Narrow definition: ICD-9 code 493.x Broad definition: visits for an asthma-related diagnosis; hospitalizations with asthma among the discharge diagnoses

≥4 asthma prescriptions in 1 year

≥1 asthma hospitalization

≥ 2 physician visits for asthma

Malo et al. 2008 [46] 1988 - 2002

Administrative healthcare data,

Assess direct costs of CLI and CFI for OA and their association with selected variables

Subjects receiving compensation for OA

NR

To et al. 2008 [24] 1994 - 1998

DAD database from CIHI, OHIP records, RPDB database

Describe prevalence of asthma, all-cause mortality, physician visits, and hospitalizations for asthma and all causes; seasonal and geographical variation of healthcare utilization in children

Children aged 0–9 years

≥1 asthma hospitalization or 2 asthma OHIP claims within 3 years

Prospective cohort studies

Ungar et al. 2001 [33] May - Oct 1995

Telephone interviews at 1, 3, and 6 months

Assess cost of asthma care at the patient level in children from the perspectives of society, the Ontario Ministry of Health, and the patient

Patients or caregivers filling prescriptions for bronchial inhalers

Probable asthma - a prescription for a bronchial inhaler medication in the last month (bronchodilator or corticosteroid) and reported experiencing shortness of breath, wheeze, or recurrent cough in the past

Anis et al. 2000 [34] Sept 1, 1994 - Aug 31 1995

2 hospital EDs in Saint John, NB; telephone interview for follow-up

Estimate average direct cost of illness for 4 cardiorespiratory conditions

ED visitors who completed follow-up interviews

ED visit records

Cross-sectional studies

Kohen et al. 2010 [47] Fall 1998 and Spring 1999

NLSCY

Examine associations between asthma and school functioning

Individuals aged 7–15 years with complete data on the measures of interest

Past-year wheezing or whistling in the chest and regular use of inhalers

Boulet et al. 2008 [35] April - August 2004,

Telephone survey

Assess influence of current and former smoking on self-reported asthma control and healthcare use

Adults aged 18–54 years with physician-diagnosed asthma for ≥6 months

Patient report of physician-diagnosed asthma

Iron et al. 2003 [37] 1994/1995

CNPHS data linked with OHIP

Determine the association between demographics, access to care, SES, and need (comorbidities) with actual family physician costs

Survey respondents aged ≥25 years consenting to share HC number and responses with MOHLTC

Self-reported

Thanh et al. 2009 [48] 2005

CCHS

To estimate the cost of asthma-related productivity loss days due to absenteeism and presenteeism* in Alberta

Survey respondents aged 18–64 years

Patient report of an asthma diagnosis

Health economic analysis

Seung et al. 2005 [42] 2004

NACRS at CIHI, OCCI, MOHLTC billing

Determine the use of urgent care resources and the annual costs of the uncontrolled asthmatic population in Canada

NR

ICD-9 code 493