Appendix Table 1. Summary of data collection.
Quarterly data collection was to occur at months 3, 6, 9, and 12.
| Measure | At enrollment (Baseline) |
Quarterly | 12 months or final Visit |
|---|---|---|---|
| Outcomes | |||
| Asthma control* | X | X | X |
| Asthma-related quality of life† | X | X | X |
| ED visits for asthma or any cause | X | X | X |
| FEV1‡ | X | X | |
| Prednisone bursts§ | X | X | X |
| Hospitalizations for asthma or any cause | X | X | X |
| Mediators (intermediate end points) | |||
| Appointments kept with asthma doctor | X | X | X |
| Use of patient portal | X | X | X |
| Inhaler Adherence Scale∥ | X | X | X |
| Covariates for identifying subgroups | |||
| Socio-demographics | X | ||
| Computer at home | X | ||
| Convenience of internet access | X | ||
| Educational attainment | X | ||
| Health literacy: S-TOFHLA¶, ANQ**, eHEALS†† | X | ||
| Comorbidities | X | ||
| Depressive thoughts‡‡ | X | ||
| Primary language | X |
ED= emergency department
Asthma control, the primary outcome, was assessed with the Asthma Control Questionnaire (ACQ). The ACQ has 6 items each scored from 0-6 with lower score indicating better control.2-4
Asthma-related quality of life was measured with the 15-item Mini Asthma-related Quality of Life Questionnaire (AQLQ).5-8 Items are scored on a 1 to 7 scale with higher scores indicating better asthma-related quality of life. The overall AQLQ score is the mean of scores of the individual items. The AQLQ is a useful indicator of asthma-related quality of life in low-income adults.9
For both ACQ and AQLQ a within-person change of at least 0.5 points is considered clinically meaningful.4,5
FEV1 could be collected for only 203 patients owing to non-availability of spirometry equipment at the start of the study. For that reason, it was not used in analysis.
Prednisone bursts are defined as a new prescription or an increase in dose of prednisone.
The Inhaler Adherence Scale asks participant’s report of non-adherence.10,11 It is a 6-item scale with each item scored 1 (non-adherence) or 0 (adherence. The range is 0-6, with 0 being optimal adherence.
S-TOFHLA= Short Test of Functional Health Literacy in Adults,12
ANQ = Asthma Numeracy Questionnaire13
eHEALS= eHealth Literacy Scale14
Center for Epidemiologic Studies Depression Scale (CES-D) has 20 items with 4-point Likert scale. The score ranges from 0 to 60 with scores >=16 suggestive of depressive symptoms or general distress.15