BACKGROUND AND OBJECTIVE: Asthma heterogeneity causes difficulty in studying and treating the disease. We built a comprehensive statewide repository linking questionnaire and medical record data with health outcomes to characterize the variability of clinical practices at Ohio children’s hospitals for the treatment of hospitalized asthma. METHODS: Children hospitalized at 6 participating Ohio children’s hospitals for asthma exacerbation or reactive airway disease aged 2 to 17 were eligible. Medical, social, and environmental histories and past asthma admissions were collected from questionnaires and the medical record. RESULTS: From December 2012 to September 2013, 1012 children were enrolled. There were significant differences in the population served, emergency department and inpatient practices, intensive care unit usage, discharge criteria, and length of stay across the sites (all P < .0001, total n = 1012). Public insurance was highest in Cleveland and Cincinnati (72 and 65%). In the emergency department, Cincinnati and Akron had the highest intravenous magnesium sulfate use (37% and 33%); Columbus administered the most intramuscular epinephrine (15%). Cleveland and Columbus had the highest intensive care unit admittance (44% and 41%) and proportion of long-stay patients (95% and 85%). Moderate/severe asthma severity classification was associated with discharge prescription for inhaled corticosteroids (odds ratio = 2.7; 95% confidence interval: 1.6–4.5; P = .004) but not stay length. CONCLUSIONS: These data highlight the need for standardization of treatment practices for inpatient asthma care. There is considerable opportunity for personalized care plans that incorporate a patient’s asthma impairment, risk, and treatment response history into hospital practices for asthma exacerbation treatment. The Ohio Pediatric Asthma Repository is a unique statewide resource in which to conduct observational, comparative effectiveness, and ultimately intervention studies for pediatric asthma.