Table 2.
Changes in Office Visits Associated With Proportional Increases in Secure Message Threads and Telephone Encounters
| Model and Variable | Change With 10% Increase in Secure Messaging Threads % (95% CI) | Change With 10% Increase in Telephone Encounters % (95% CI) |
|---|---|---|
| Adjusted modela | ||
| Full study population | 1.25 (1.21–1.29) | 2.74 (2.70–2.77) |
| Interaction modela | ||
| Study period | ||
| Baseline | 1.13 (0.89–1.38) | 2.93 (2.70–3.15)b |
| PCMH implementation (Ref) | 1.14 (0.93–1.35) | 2.74 (2.55–2.93) |
| Postimplementation | 1.20 (0.98–1.41) | 2.57 (2.38–2.77)c |
| Age-group, y | ||
| 18–44 | 1.28 (1.03–1.53) | 2.93 (2.70–3.17)b |
| 45–54 | 1.21 (0.99–1.43) | 2.94 (2.74–3.14)b |
| 55–64 (Ref) | 1.14 (0.93–1.35) | 2.74 (2.55–2.93) |
| 65–75 | 1.22 (0.93–1.50) | 2.81 (2.56–3.06) |
| Sex | ||
| Female (Ref) | 1.14 (0.93–1.35) | 2.74 (2.55–2.93) |
| Male | 1.18 (0.97–1.39) | 2.62 (2.43–2.81)c |
| Morbidity burden (ACG RUB) | ||
| Moderate (Ref) | 1.14 (0.93–1.35) | 2.74 (2.55–2.93) |
| High | 0.84 (0.62–1.06)c | 2.66 (2.46–2.86)c |
| Very high | 0.69 (0.45–0.93)c | 2.72 (2.51–2.93) |
| Insurance type | ||
| Commercial (Ref) | 1.14 (0.93–1.35) | 2.74 (2.55–2.93) |
| Medicaid/state-subsidized | 1.00 (0.63–1.38) | 3.16 (2.83–3.48)b |
| Medicare | 0.96 (0.68–1.23) | 2.78 (2.53–3.03) |
ACG = adjusted clinical group; PCMH = patient-centered medical home; Ref = referent category; RUB=resource utilization band.
Note: Results are from log-linear regression models.
Adjusted for age, sex, morbidity burden, insurance type, clinician network, well-care waiver, pharmaceutical coverage, education, income, baseline secure messaging use, hemoglobin A1c level, blood pressure, low-density lipoprotein cholesterol level, study period, calendar quarter, physician secure messaging, and physician telephone encounter use.
Positive effect modification at P ≤.05, compared with referent category.
Negative effect modification at P ≤.05, compared with referent category.