Table 3.
Uptake of Mail Order Pharmacy Use (MOP) Following Baseline Date of Pharmacy Benefit Change, Benefit Change Effect, and Effect Difference (Difference in Benefit Change Effect Across Social Groups) in a Cohort of 10,590 Diabetes Patients
| MOP Uptake | Benefit Change Effect* | Effect Difference§ (95% CI) | |||
|---|---|---|---|---|---|
| Pharmacy Benefit Changed | No Benefit Change | Unadjusted (95% CI) | Adjusted‡ (95% CI) | ||
| All subjects | 0.30 | 0.09 | 0.21 (0.19, 0.23) | 0.26 (0.22,0.30) | — |
| Income | |||||
| <$25K (ref) | 0.25 | 0.08 | 0.18 (0.14, 0.21) | 0.26 (0.19, 0.32) | — |
| $25K–$49K | 0.32 | 0.08 | 0.24 (0.20, 0.28)† | 0.21 (0.14, 0.29) | −0.05 (−0.15, 0.05) |
| $50K–$79K | 0.34 | 0.08 | 0.25 (0.20, 0.31)† | 0.34 (0.23, 0.46) | 0.08 (−0.05, 0.22) |
| $80K+ | 0.37 | 0.12 | 0.26 (0.19, 0.32)† | 0.27 (0.14, 0.40) | 0.02 (−0.13, 0.16) |
| Race | |||||
| Caucasian (ref) | 0.44 | 0.12 | 0.32 (0.28, 0.37) | 0.37 (0.31, 0.44) | — |
| African Am. | 0.21 | 0.08 | 0.13 (0.09, 0.18)† | 0.25 (0.14, 0.38) | −0.12 (−0.25, 0.04) |
| Asian | 0.39 | 0.11 | 0.28 (0.22, 0.34) | 0.21 (0.10, 0.34)† | −0.16 (−0.30, −0.001)† |
| Filipino | 0.25 | 0.08 | 0.17 (0.11, 0.23)† | 0.22 (0.10, 0.37) | −0.15 (−0.29, 0.02) |
| Latino | 0.21 | 0.06 | 0.15 (0.12, 0.19)† | 0.14 (0.07, 0.20)† | −0.24 (−0.33, −0.14)† |
| Education | |||||
| No degree (ref) | 0.25 | 0.07 | 0.18 (0.14, 0.22) | 0.22 (0.15, 0.30) | — |
| HS/GED | 0.29 | 0.09 | 0.20 (0.16, 0.24) | 0.26 (0.19, 0.33) | 0.04 (−0.07, 0.14) |
| Some college | 0.33 | 0.09 | 0.25 (0.20, 0.29)† | 0.23 (0.16, 0.32) | 0.01 (−0.10, 0.13) |
| College+ | 0.38 | 0.10 | 0.29 (0.24, 0.34)† | 0.31 (0.21, 0.41) | 0.09 (−0.05, 0.21) |
| Limited English proficiency | |||||
| No (ref) | 0.33 | 0.09 | 0.24 (0.21, 0.27) | 0.27 (0.23, 0.32) | — |
| Yes | 0.21 | 0.06 | 0.15 (0.10, 0.20)† | 0.13 (0.06, 0.21)† | −0.14 (−0.22, −0.05)† |
| Inadequate health literacy | |||||
| No (ref) | 0.40 | 0.09 | 0.31 (0.27, 0.35) | 0.35 (0.27, 0.42) | — |
| Yes | 0.26 | 0.08 | 0.18 (0.15, 0.21)† | 0.20 (0.14, 0.26)† | −0.15 (−0.24, −0.05)† |
| Financial hardship | |||||
| No (ref) | 0.36 | 0.09 | 0.27 (0.23, 0.30) | 0.31 (0.24, 0.37) | — |
| Yes | 0.26 | 0.09 | 0.19 (0.16, 0.22)† | 0.24 (0.17, 0.31) | −0.07 (−0.16, 0.02) |
Benefit change effect is estimated by the MOP uptake among those with a benefit change after subtracting the uptake in those without a benefit change (to “net out” the MOP uptake due to secular time trends among those not affected by the benefit change). All risk differences in table were significant at the <.05 level for H0: RD = 0.
Indicates statistical significance at the ≤.05 level for H0: RD(level) = RD(reference).
Poisson model with identity link function, models weighted for inverse probability of treatment weights (IPTW), expansion weights for race-stratified sampling design, and survey nonresponse (Horvitz–Thompson weighting). The IPTW model included baseline age, out-of-pocket drug copay, benefits based copay for brand drugs, Medicare indicator, deductible drug plan indicator, drug benefit business line (e.g., large employer group, small employer group, strategic group), and our socioeconomic indicators (ethnicity, income, education, limited English proficiency, inadequate health literacy, or financial hardship); weights were truncated at the 99th percentile. Confidence intervals calculated using 1,000 bootstrap samples in the adjusted models.
Effect difference is the absolute difference in the adjusted benefit change effect between a given social strata and the reference social strata.