TABLE II.

Methods for measuring and reporting core and supplemental outcome measures for healthcare utilization and costs

Outcome	Measure/report method
All healthcare events	Preferred method for prospective studies is structured clinical encounter forms, patient or family-reported data (2-week recall period for low-impact events such as office visit, ≤6 month recall for major events such as hospitalization) Report as: Count each healthcare event as an independent contribution (in contrast to an episode of care, which may include multiple events). For ≥12-month studies, report as annual counts and/or rates. Extrapolation in studies of shorter duration is not recommended. Rates of healthcare events should use an appropriate denominator (eg, the population at risk for the outcome) and a common denominator when rates are compared. Report: ○ Mean, median, and interquartile range ○ Optional additional measure: proportion of the group with none versus any number of events
Asthma-specific healthcare events and resource utilization Hospital admission (asthma related) Hospital admission (respiratory related, in patients who have asthma) ED visits	Hospital-asthma admission preferred method: Length of stay and ICU days. Alternative: Average length of stay for study population. If administrative data, ≥24 hour stay required, describe how admission, readmission, and transfer are defined. Report ≤23 hour asthma observation stays separately. Hospital/ED visit costs: ○ Preferred: study- or institution-specific payments, if available. Alternative: use standard sources of cost estimation (eg, hospital cost-to-charge ratio). ○ Disclose unit costs wherever possible.
Outpatient visits ○ Scheduled (preventive) ○ Unscheduled ○ Subspecialist care ○ Remote care	Outpatient visits: ○ Scheduled: Count comprehensive scheduled health visits for asthma patients, asthma-specific preventive visits, and visits scheduled at least 72 hours in advance. ○ Unscheduled: Count patient-initiated visits resulting from worsening symptoms. ○ Subspecialty: Count separately, and categorize as scheduled and unscheduled visits. ○ Remote visits: e-mail, telephone, consults. Costs: No standardized method; if rates are not established, use mean or median paid amounts per call for nurse triage service as estimate; or costs estimate of clinical/staff time to handle email/telephone consult.
Outpatient costs	Outpatient costs ○ In administrative data, use CPT codes; use E/M codes to identify level of service (eg, spirometry, inhalation therapy, pulse oximetry, and where reported, patient education/counseling). ○ If actual paid amounts not available, use Medicare adjusted allowable limits associated with these CPT codes.
Respiratory outpatient and ED visits and hospitalizations	Respiratory visit and admission diagnostic categories—for example, ICD-9CM codes 422,427–428, 460–466, 470–474,480–487, and 490–519.
Intervention-related resources Medication Supplies Patient costs Personnel time	Measure resource use that may not be captured in healthcare claims and encounter data. Research costs (design, implementation, evaluation) should not be included). Report medication name, dose duration. Report utilization by class of medication per person per year. Report purchase cost. Report time invested for treatment and travel. Methods include time-and-motion studies and work sampling. Report as personnel cost per study participant per year.
Other asthma-related events Absenteeism ○ School ○ Work	Count days missed from school (preferably days missed due to asthma). Report rates for 12-month periods, as mean, median, and interquartile range. Use WPAI (http://www.reillyassociates.net/WPAI_General.html) to count work absence days. Report as total counts, mean number of days, rates, and the proportion of study participants with at least 1 absence day. Summary reports include mean, median, and interquartile range with 12-month rates and appropriate denominators (eg, those employed). May also use WPAI measure of percentage of missed work time due to asthma symptoms.
Presenteeism ○ School ○ Work	Use Teacher Report Form of Child Behavior Checklist (http://www.aseba.org/products/forms.html) or standardized test scores. WPAI can be used to collect a school impairment measure for older children. WPAI instrument measures reduced effectiveness while working.
Cost-effectiveness analysis	See Section II: Cost and Cost-Effectiveness Analysis.

CPT, current procedural terminology; ED, emergency department; E/M, evaluation and management; ICU, intensive care unit; ICD-9CM, International Classification of Diseases, Ninth Revision, Clinical Modification; WPAI, Work Productivity and Activity Impairment Questionnaire.