Table 3.
Adjusted Model: Factors Associated with Ordering, Including Stratification by BBW
| Variable | Unstratified Fully Adjusted Model N = 60,347 OR [95 % CI] | Stratified Models | |
|---|---|---|---|
| Non-BBW pairs N = 51,132 OR [95 % CI] | BBW pairs N = 9,215 OR [95 % CI] | ||
| Patient gender | |||
| Male | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Female | 0.83 [0.75 – 0.92] | 0.85 [0.76 – 0.94] | 0.79 [0.64 – 0.98] |
| Patient age | |||
| < 40 years old | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 40–50 | 1.38 [1.21 – 1.57] | 1.14 [0.98 – 1.33] | 1.45 [1.12 – 1.88] |
| 50–60 | 1.74 [1.56 – 1.95] | 1.38 [1.21 – 1.57] | 1.96 [1.51 – 2.56] |
| 60–70 | 2.25 [1.95 – 2.58] | 1.73 [1.48 – 2.01] | 3.06 [2.28 – 4.12] |
| 70–80 | 2.19 [1.89 – 2.54] | 1.68 [1.41 – 2.00] | 3.36 [2.57 – 4.39] |
| ≥ 80 | 2.04 [1.73 – 2.41] | 1.59 [1.30 – 1.93] | 3.06 [2.29 – 4.08] |
| Number of patient visits, by quartile | |||
| 0–5 visits | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 6–10 visits | 1.65 [1.50 – 1.82] | 1.64 [1.48 – 1.81] | 2.00 [1.58 – 2.53] |
| 11–18 visits | 2.02 [1.78 – 2.30] | 2.04 [1.78 – 2.34] | 2.38 [1.91 – 2.97] |
| ≥ 19 visits | 2.63 [2.26 – 3.06] | 2.56 [2.19 – 3.00] | 4.54 [3.55 – 5.80] |
| Number of study medications patient is taking | |||
| Single medication | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Multiple medications | 1.55 [1.43 – 1.68] | 1.55 [1.44 – 1.68] | 1.77 [1.46 – 2.14] |
| Number of providers per patient | |||
| One | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| More than one | 0.98 [0.88 – 1.10] | 0.97 [0.87 – 1.09] | 1.00 [0.78 – 1.27] |
| Provider gender | |||
| Male | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Female | 0.81 [0.58 – 1.13] | 0.82 [0.58 – 1.15] | 0.82 [0.54 – 1.23] |
| Provider age | |||
| < 40 years old | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 40–50 years old | 0.80 [0.52 – 1.23] | 0.81 [0.51 – 1.27] | 0.60 [0.34 – 1.06] |
| 50–60 years old | 0.71 [0.40 – 1.28] | 0.67 [0.37 – 1.20] | 0.86 [0.35 – 2.10] |
| > 60 years old | 0.30 [0.13 – 0.70] | 0.30 [0.12 – 0.72] | 0.48 [0.14 – 1.64] |
| Provider specialty | |||
| Specialist | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| PCP | 0.71 [0.45 – 1.10] | 1.01 [0.68 – 1.52] | 0.30 [0.15 – 0.62] |
| Patients per provider | |||
| First quartile (1 patient) | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Second quartile (2–11) | 2.16 [0.93 – 5.02] | 2.19 [0.69 – 6.92] | 2.33 [0.86 – 6.31] |
| Third quartile (12–179) | 2.77 [1.22 – 6.30] | 2.16 [0.72 – 6.51] | 4.65 [1.85 – 11.70] |
| Fourth quartile (≥ 190) | 3.38 [1.49 – 7.64] | 2.65 [0.87 – 8.02] | 5.15 [2.12 – 12.55] |
| Working status | |||
| Part-time | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Full time | 1.05 [0.75 – 1.48] | 1.13 [0.81 – 1.59] | 0.86 [0.53 – 1.39] |
| Years of experience, per year | 1.00 [0.97 – 1.03] | 1.00 [0.97 – 1.03] | 1.00 [0.96 – 1.04] |
| Prescription type | |||
| Chronic use | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| New use | 0.52 [0.48 – 0.56] | 0.57 [0.52 – 0.62] | 0.39 [0.31 – 0.49] |
| Evidence for test | |||
| Recommended test | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| BBW | 1.78 [1.49 – 2.13] | ||
| Guidelines | 1.31 [1.10 – 1.56] | ||
| Test frequency | |||
| Yearly | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| More frequent | 0.38 [0.29 – 0.49] | 0.51 [0.39 – 0.65] | 0.18 [0.13 – 0.24] |
| Number of tests recommended for this medication | |||
| Single | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Multiple | 0.48 [0.40 – 0.57] | 0.43 [0.37 – 0.51] | 0.62 [0.38 – 0.99] |
Abbreviations: BBW black box warning; CI confidence interval; OR odds ratio; PCP primary care provider